Two IBM/Lenovo ThinkPads over a wireless network
Alan
Lenovo ThinkPads to work over our wireless network (see http://
groups.google.com/group/comp.sys.laptops.thinkpad/browse_thread/thread/
27ab28434e118e0f/6f6779b235421b1d?
lnk=st&q=Garny&rnum=5#6f6779b235421b1d). One of them is a T42p and the
other a X41.
The X41 was recently bought to replace an old laptop, which used to
work fine with the T42p over our wireless network. Since we have
replaced that old laptop with the X41, things have just stopped
working: we lose our wireless connection on both the T42p and X41
within a few minutes of being connected.
Tonight, I thought I would shut down the X41 and start the old laptop,
and see how it behaves together with the T42p and, unsurprisingly,
everything is working as it should: no wireless connection being lost.
So, that really tells me that there is a problem between my T42p and
X41. They just don't seem to be willing to live together on the same
wireless network. Why though?
Alan.
John Navas
On 9 Feb 2007 14:48:38 -0800, "Alan" <aga...@gmail.com> wrote in
<1171061318.8...@l53g2000cwa.googlegroups.com>:
>Hi, I have been struggling for some time trying to get my two IBM/
>Lenovo ThinkPads to work over our wireless network (see http://
>groups.google.com/group/comp.sys.laptops.thinkpad/browse_thread/thread/
>27ab28434e118e0f/6f6779b235421b1d?
>lnk=st&q=Garny&rnum=5#6f6779b235421b1d). One of them is a T42p and the
>other a X41.
>
>The X41 was recently bought to replace an old laptop, which used to
>work fine with the T42p over our wireless network. Since we have
>replaced that old laptop with the X41, things have just stopped
>working: we lose our wireless connection on both the T42p and X41
>within a few minutes of being connected.
What _exactly_ does lose the connection mean? Red X on icon is system
tray? Just can't surf? What?
>Tonight, I thought I would shut down the X41 and start the old laptop,
>and see how it behaves together with the T42p and, unsurprisingly,
>everything is working as it should: no wireless connection being lost.
>
>So, that really tells me that there is a problem between my T42p and
>X41. They just don't seem to be willing to live together on the same
>wireless network. Why though?
What controls the wireless network? Exact make, model, version, and
firmware of wireless router or access point please.
--
Best regards,
John Navas
Alan
> tray? Just can't surf? What?
It means that I cannot access my modem/router anymore and therefore
cannot do anything that involves my network and, as a consequence, the
internet (i.e. impossible to browse, receive email, etc.).
> >Tonight, I thought I would shut down the X41 and start the old laptop,
> >and see how it behaves together with the T42p and, unsurprisingly,
> >everything is working as it should: no wireless connection being lost.
>
> >So, that really tells me that there is a problem between my T42p and
> >X41. They just don't seem to be willing to live together on the same
> >wireless network. Why though?
>
> What controls the wireless network? Exact make, model, version, and
> firmware of wireless router or access point please.
I use a D-Link DSL-G624T with the V3.00B01T02.UK-A.20060621 firmware.
Note that I have tried other firmwares (cannot recall which though)
and got exactly the same problem. Also, note that using the above
modem/router with the above firmware, I have NO problem whatsoever
when using my T42p with *another* laptop (Hi-Grade Notino W6700).
Things that I have tried include (in no particular order): access list
(i.e. with and without access limited by MAC address), various
encryptions (i.e. no encryption, WEP and WPA/PSK), DHCP (i.e. no DHCP,
DHCP without static IP assignment, and DHCP with static IP
assignment), and maybe other things that I cannot recall for having
tried so many things!
I would, somehow, be surprised if the problem was with my modem/
router, unless ThinkPads don't like that particular make (who knows?).
Anyway, this is extremely frustrating and would appreciate any help...
Alan.
John Navas
<1171098751.8...@k78g2000cwa.googlegroups.com>:
>> What _exactly_ does lose the connection mean? Red X on icon is system
>> tray? Just can't surf? What?
>
>It means that I cannot access my modem/router anymore and therefore
>cannot do anything that involves my network and, as a consequence, the
>internet (i.e. impossible to browse, receive email, etc.).
Again, what _exactly_ does "cannot access" mean?
What does the network icon look like and say?
What it should look like: http://i5.tinypic.com/40e4oea.png
>> What controls the wireless network? Exact make, model, version, and
>> firmware of wireless router or access point please.
>
>I use a D-Link DSL-G624T with the V3.00B01T02.UK-A.20060621 firmware.
Thanks.
>Things that I have tried include (in no particular order): access list
>(i.e. with and without access limited by MAC address), various
>encryptions (i.e. no encryption, WEP and WPA/PSK), DHCP (i.e. no DHCP,
>DHCP without static IP assignment, and DHCP with static IP
>assignment), and maybe other things that I cannot recall for having
>tried so many things!
Have you tried the ThinkPad in a public Wi-Fi hotspot?
>I would, somehow, be surprised if the problem was with my modem/
>router, unless ThinkPads don't like that particular make (who knows?).
What matters is the make and model of the Wi-Fi adapter and the software
used to control it -- there's nothing special about the ThinkPad. My
own T41 uses an Atheros mini PCI card with Windows XP WZC.
--
Best regards, FAQ for Wireless Internet: <http://Wireless.wikia.com>
John Navas FAQ for Wi-Fi: <http://wireless.wikia.com/wiki/Wi-Fi>
Wi-Fi How To: <http://wireless.wikia.com/wiki/Wi-Fi_HowTo>
Fixes to Wi-Fi Problems: <http://wireless.wikia.com/wiki/Wi-Fi_Fixes>
Alan
> On 10 Feb 2007 01:12:31 -0800, "Alan" <aga...@gmail.com> wrote in
>
> >> What _exactly_ does lose the connection mean? Red X on icon is system
> >> tray? Just can't surf? What?
>
> >It means that I cannot access my modem/router anymore and therefore
> >cannot do anything that involves my network and, as a consequence, the
> >internet (i.e. impossible to browse, receive email, etc.).
>
> Again, what _exactly_ does "cannot access" mean?
?!?!?!?!
> What does the network icon look like and say?
> What it should look like:http://i5.tinypic.com/40e4oea.png
I know how it should look like and it doesn't look like that at all.
Sorry, but I am not willing to get the two ThinkPads online if I can
avoid it. The whole situation is really pissing my partner off as she
needs an internet connection for her work (in other words: we are only
ever running one of the ThinkPads and her old laptop, since that's the
*only* combination that works). Anyway, independent of how the icon
actually looks like, it clearly tells me that the laptop is NOT
connected to my modem/router and therefore to the internet, as
mentioned above when I say that I cannot browse the internet, receive
emails, etc. Sorry, if I am being a bit impatient, but I am really
getting annoyed with it all. I have spent, not to say wasted, hours
(which probably add up to days by now) trying lots of different
settings and all I can tell you is that to have two ThinkPads running
means that the icon changes from 'connected' to 'disconnected' within
a minute or a few minutes at best. If, on the other hand, I have only
one laptop running, then everything is fine. In both cases, it doesn't
matter whether my partner's old laptop is running or not.
> >Things that I have tried include (in no particular order): access list
> >(i.e. with and without access limited by MAC address), various
> >encryptions (i.e. no encryption, WEP and WPA/PSK), DHCP (i.e. no DHCP,
> >DHCP without static IP assignment, and DHCP with static IP
> >assignment), and maybe other things that I cannot recall for having
> >tried so many things!
> Have you tried the ThinkPad in a public Wi-Fi hotspot?
I have never tried the X41 anywhere but at my place, while I have
tried the T42p all over the world (literally) and have never had any
problem with it when trying to connect it to a wireless network.
> >I would, somehow, be surprised if the problem was with my modem/
> >router, unlessThinkPadsdon't like that particular make (who knows?).
> What matters is the make and model of the Wi-Fi adapter and the software
> used to control it -- there's nothing special about the ThinkPad. My
> own T41 uses an Atheros mini PCI card with Windows XP WZC.
Ok, fine, so how do I go about determining whether there is or not a
conflict between my X41's wireless adapter and software and that of my
T42p? Are there known issues of the sort?
Alan.
John Navas
<1171211901.1...@v33g2000cwv.googlegroups.com>:
>On 11 Feb, 16:00, John Navas <spamfilt...@navasgroup.com> wrote:
>> On 10 Feb 2007 01:12:31 -0800, "Alan" <aga...@gmail.com> wrote in
>> <1171098751.896024.242...@k78g2000cwa.googlegroups.com>:
>>
>> >> What _exactly_ does lose the connection mean? Red X on icon is system
>> >> tray? Just can't surf? What?
>>
>> >It means that I cannot access my modem/router anymore and therefore
>> >cannot do anything that involves my network and, as a consequence, the
>> >internet (i.e. impossible to browse, receive email, etc.).
>>
>> Again, what _exactly_ does "cannot access" mean?
>
>?!?!?!?!
What's that supposed to mean? I can't help you if you don't provide the
information.
>> What does the network icon look like and say?
>> What it should look like:http://i5.tinypic.com/40e4oea.png
>
>I know how it should look like and it doesn't look like that at all.
So what does it look like?
>Sorry, but I am not willing to get the two ThinkPads online if I can
>avoid it.
[shrug]
>The whole situation is really pissing my partner off as she
>needs an internet connection for her work (in other words: we are only
>ever running one of the ThinkPads and her old laptop, since that's the
>*only* combination that works). Anyway, independent of how the icon
>actually looks like, it clearly tells me that the laptop is NOT
>connected to my modem/router and therefore to the internet, as
>mentioned above when I say that I cannot browse the internet, receive
>emails, etc. Sorry, if I am being a bit impatient, but I am really
>getting annoyed with it all.
Sorry, but I can't help you if you going to be impatient like that.
>Ok, fine, so how do I go about determining whether there is or not a
>conflict between my X41's wireless adapter and software and that of my
>T42p? Are there known issues of the sort?
No. You're making things up and thrashing around. Calm down, answer my
questions, and I may be able to help you.
Alan
> >> >cannot do anything that involves my network and, as a consequence, the
> >> >internet (i.e. impossible to browse, receive email, etc.).
>
> >> Again, what _exactly_ does "cannot access" mean?
>
> >?!?!?!?!
>
> What's that supposed to mean? I can't help you if you don't provide the
> information.
I believe to have provided you with the information, but I am
obviously wrong...
> >> What does the network icon look like and say?
> >> What it should look like:http://i5.tinypic.com/40e4oea.png
>
> >I know how it should look like and it doesn't look like that at all.
>
> So what does it look like?
Ok, I have googled around for a picture that looks like what I get:
http://www.itap.purdue.edu/airlink/images/vpnpc1a.jpg
> >Ok, fine, so how do I go about determining whether there is or not a
> >conflict between myX41'swirelessadapter and software and that of my
> >T42p? Are there known issues of the sort?
>
> No. You're making things up and thrashing around. Calm down, answer my
> questions, and I may be able to help you.
The only question I hadn't properly answered is how the icon looks
like. You now know how it looks like and, as you can tell (unless I am
completely mistaken), it does correspond to what I have described in
words rather than through a picture. So, what does the picture tell
you that you didn't know before?
Otherwise, I am still of the view that there is an issue with the two
ThinkPads. Maybe it's hardware, maybe it's software, or maybe it's a
combination of the two (through their respective settings)?
Anyway, I cannot test anything anymore, it would seem that my T42p's
screen just died on me. It just went completely black for no apparent
reason. If I restart my T42p, its screen may or not work and if it
does, it will freeze after a while, while the rest of the system seems
to boot up, etc. Having no external screen, I cannot determine for
sure what the cause of the problem is.
Anyway #2, I do appreciate your help, but there indeed seems to be a
problem of communication. Maybe we should just give up... not a good
day for me it would seem...
John Navas
<1171217260.6...@a34g2000cwb.googlegroups.com>:
>> >> >It means that I cannot access my modem/router anymore and therefore
>> >> >cannot do anything that involves my network and, as a consequence, the
>> >> >internet (i.e. impossible to browse, receive email, etc.).
>>
>> >> Again, what _exactly_ does "cannot access" mean?
>>
>> >?!?!?!?!
>>
>> What's that supposed to mean? I can't help you if you don't provide the
>> information.
>
>I believe to have provided you with the information, but I am
>obviously wrong...
"?!?!?!?!" is information? Were you trying to be funny?
Again, what _exactly_ does "cannot access" mean? I can't read your mind
or see what's on your computer display. I need _exact_ symptoms.
>> >> What does the network icon look like and say?
>> >> What it should look like:http://i5.tinypic.com/40e4oea.png
>>
>> >I know how it should look like and it doesn't look like that at all.
>>
>> So what does it look like?
>
>Ok, I have googled around for a picture that looks like what I get:
>http://www.itap.purdue.edu/airlink/images/vpnpc1a.jpg
That helps a bit, but is just a start. Your wireless icon says "not
connected". What do you see in "view available wireless networks"?
What happens _exactly_ whey you select your wireless network (if you
can) and click Connect? If it tries for a time and then eventually
can't connect, have you turned off _all_ wireless security? To be sure,
reset the wireless router or access point to hardware defaults, and
start over without enabling any security. What happens with a wired
instead of wireless connection to either computer?
>> No. You're making things up and thrashing around. Calm down, answer my
>> questions, and I may be able to help you.
>
>The only question I hadn't properly answered is how the icon looks
>like.
On the contrary -- I've asked more than once "what _exactly_ does
'cannot access' mean?" It would help greatly if you took the time and
effort to _exactly_ describe what is happening, instead of just saying
"cannot access", which could be a great many different things. I'm not
interested in guessing / taking stabs in the dark.
>Otherwise, I am still of the view that there is an issue with the two
>ThinkPads. Maybe it's hardware, maybe it's software, or maybe it's a
>combination of the two (through their respective settings)?
I think that view is almost certainly wrong. One wireless client won't
kill another wireless client (assuming it didn't kill the wireless
router or access point).
>Anyway, I cannot test anything anymore, it would seem that my T42p's
>screen just died on me. It just went completely black for no apparent
>reason. If I restart my T42p, its screen may or not work and if it
>does, it will freeze after a while, while the rest of the system seems
>to boot up, etc. Having no external screen, I cannot determine for
>sure what the cause of the problem is.
That's very serious, might well be related to other problems, and should
be fixed first.
>Anyway #2, I do appreciate your help, but there indeed seems to be a
>problem of communication. Maybe we should just give up... not a good
>day for me it would seem...
Fair enough.
Mark McIntyre
<aga...@gmail.com> wrote:
>On 11 Feb, 16:00, John Navas <spamfilt...@navasgroup.com> wrote:
>> On 10 Feb 2007 01:12:31 -0800, "Alan" <aga...@gmail.com> wrote in
>> <1171098751.896024.242...@k78g2000cwa.googlegroups.com>:
>>
>> >> What _exactly_ does lose the connection mean? Red X on icon is system
>> >> tray? Just can't surf? What?
>>
>> >It means that I cannot access my modem/router anymore and therefore
>> >cannot do anything that involves my network and, as a consequence, the
>> >internet (i.e. impossible to browse, receive email, etc.).
>>
>> Again, what _exactly_ does "cannot access" mean?
>
>?!?!?!?!
Can't browse?
Cant get email either?
Cant ping the router?
Cant ping the other machine?
WZC says connected but some/all of the above?
WZC says "limited connection?"
What?
>settings and all I can tell you is that to have two ThinkPads running
>means that the icon changes from 'connected' to 'disconnected' within
>a minute or a few minutes at best. If, on the other hand, I have only
>one laptop running, then everything is fine.
Sounds to me like they have the same IP address. How about manually
configuring htem to different addresses.
>Ok, fine, so how do I go about determining whether there is or not a
>conflict between my X41's wireless adapter and software and that of my
>T42p?
I can't see how the two sets of wireless hw/sw could interfere with
each other. By definition, anything standards compliant is
interoperable.
--
Mark McIntyre
Alan
> >> What's that supposed to mean? I can't help you if you don't provide the
> >> information.
> >I believe to have provided you with the information, but I am
> >obviously wrong...
> "?!?!?!?!" is information? Were you trying to be funny?
No, I was not. Otherwise, I was not referring to the "?!?!?!?!", but
to the other things I have mentioned in my other messages. Huge
problem of communication indeed. Must be me, I am French after all.
> Again, what _exactly_ does "cannot access" mean? I can't read your mind
> or see what's on your computer display. I need _exact_ symptoms.
If you were to tell me the kind of answer you are expecting from me,
then maybe I could tell you exactly what is going on? In the same way
you cannot read my mind, I surely cannot read yours.
> >Ok, I have googled around for a picture that looks like what I get:
> >http://www.itap.purdue.edu/airlink/images/vpnpc1a.jpg
> That helps a bit, but is just a start. Yourwirelessicon says "not
> connected". What do you see in "view availablewirelessnetworks"?
Most ofthen than not, my modem/router won't show up. I have to stop it
and restart it to see it listed again. Other times, it will show up,
but I won't be able to connect to it. Again, by stopping it and
restarting it, it shows up and I will be able to connect to it. But,
as I have said several times, this will only be temporary if I have
both ThinkPads running.
> What happens _exactly_ whey you select yourwirelessnetwork (if you
> can) and click Connect? If it tries for a time and then eventually
> can't connect, have you turned off _all_wirelesssecurity? To be sure,
> reset thewirelessrouter or access point to hardware defaults, and
> start over without enabling any security. What happens with a wired
> instead ofwirelessconnection to either computer?
I have done all those things before (see my very second message). The
only thing I didn't mention (but did in the *other* thread I refer to
in my first message in *this* thread) is that everything works fine
when I use a wired connection. It is only when I try to connect
wirelessly that things start playing up.
> >Otherwise, I am still of the view that there is an issue with the two
> >ThinkPads. Maybe it's hardware, maybe it's software, or maybe it's a
> >combination of the two (through their respective settings)?
> I think that view is almost certainly wrong. Onewirelessclient won't
> kill anotherwirelessclient (assuming it didn't kill thewireless
> router or access point).
I am only basing my 'conclusion' on what I am experiencing. Two
ThinkPads (T42p and X41) together trying to wirelessly connect to my D-
Link DSL-G624T modem/router results in both of them losing their
connection. If only one of them is connected, then everything's fine.
If I knew exactly what the problem is, I surely wouldn't be here
trying to get an answer for what has been bugging me for quite some
time.
Alan.
Alan
> >?!?!?!?!
> Can't browse?
> Cant get email either?
> Cant ping the router?
> Cant ping the other machine?
At least all of that, yes.
> WZC says connected but some/all of the above?
> WZC says "limited connection?"
> What?
I am not familiar with WZC (Wireless Zero Configuration it would
seem), so what is that exactly? Otherwise, I have indeed seen "limited
connection" and that was when I 'lost my connection' (i.e. all of the
above). From there, I had to stop and restart my modem/router to get
my wireless connection back (for a short period of time that is, if I
have both ThinkPads running).
> >settings and all I can tell you is that to have twoThinkPadsrunning
> >means that the icon changes from 'connected' to 'disconnected' within
> >a minute or a few minutes at best. If, on the other hand, I have only
> >one laptop running, then everything is fine.
> Sounds to me like they have the same IP address. How about manually
> configuring htem to different addresses.
I have checked that and they don't. I have also, at some point,
configured my modem/router so that it doesn't use DHCP and the two
ThinkPads so that they use fixed IP addresses, all of that to no
avail.
> >Ok, fine, so how do I go about determining whether there is or not a
> >conflict between myX41'swirelessadapter and software and that of my
> >T42p?
> I can't see how the two sets ofwirelesshw/sw could interfere with
> each other. By definition, anything standards compliant is
> interoperable.
I cannot explain it to myself either, hence my asking here... All I
can tell you is that to run both ThinkPads on the same wireless
network results in both of them losing their connection, while either
one works very well on its own.
Alan.
John Navas
<1171232838.2...@a75g2000cwd.googlegroups.com>:
>> Again, what _exactly_ does "cannot access" mean? I can't read your mind
>> or see what's on your computer display. I need _exact_ symptoms.
>
>If you were to tell me the kind of answer you are expecting from me,
>then maybe I could tell you exactly what is going on? In the same way
>you cannot read my mind, I surely cannot read yours.
Fair enough. Carefully note everything that is or isn't happening, step
by step, and report it fully here. See Mark's response for some of the
more obvious things you're leaving out.
>> >Ok, I have googled around for a picture that looks like what I get:
>> >http://www.itap.purdue.edu/airlink/images/vpnpc1a.jpg
>> That helps a bit, but is just a start. Yourwirelessicon says "not
>> connected". What do you see in "view availablewirelessnetworks"?
You also seem to have a problem with your newsreader deleting spaces
from quoted replies.
>Most ofthen than not, my modem/router won't show up.
Your "modem" won't ever show up.
Your router will show up if (a) it's broadcasting and (b) the wireless
client is working. If it doesn't show up, then you have one and/or the
other of those two problems.
>I have to stop it
>and restart it to see it listed again.
That suggests your router is failing.
>Other times, it will show up,
>but I won't be able to connect to it.
Different issue. Possible problems: interference, security gone wrong.
>Again, by stopping it and
>restarting it, it shows up and I will be able to connect to it.
Again, points to a router problem. You may want to try a different
router.
>But,
>as I have said several times, this will only be temporary if I have
>both ThinkPads running.
Not surprising -- routers can have problems triggered by different types
of loads. For example, many routers will fall over and die because of
the huge number of connections opened by default settings in
peer-to-peer filesharing apps.
>> What happens _exactly_ whey you select yourwirelessnetwork (if you
>> can) and click Connect? If it tries for a time and then eventually
>> can't connect, have you turned off _all_wirelesssecurity? To be sure,
>> reset thewirelessrouter or access point to hardware defaults, and
>> start over without enabling any security. What happens with a wired
>> instead ofwirelessconnection to either computer?
>
>I have done all those things before (see my very second message). The
>only thing I didn't mention (but did in the *other* thread I refer to
>in my first message in *this* thread) is that everything works fine
>when I use a wired connection. It is only when I try to connect
>wirelessly that things start playing up.
Sorry, but I'm _not_ going to chase down other threads. If you want my
help, post the information in _this_ thread.
>> >Otherwise, I am still of the view that there is an issue with the two
>> >ThinkPads. Maybe it's hardware, maybe it's software, or maybe it's a
>> >combination of the two (through their respective settings)?
>> I think that view is almost certainly wrong. Onewirelessclient won't
>> kill anotherwirelessclient (assuming it didn't kill thewireless
>> router or access point).
>
>I am only basing my 'conclusion' on what I am experiencing. ...
You are actually leaping to conclusions. What I wrote is far more
likely.
You would waste far less time if you just posted the requested
information, instead of arguing about it.
John Navas
<1171233355....@j27g2000cwj.googlegroups.com>:
>> WZC says connected but some/all of the above?
>> WZC says "limited connection?"
>> What?
>
>I am not familiar with WZC (Wireless Zero Configuration it would
>seem), so what is that exactly?
Windows XP wireless control. Are you using that, or IBM/Lenovo Access
Connections?
>Otherwise, I have indeed seen "limited
>connection" and that was when I 'lost my connection' (i.e. all of the
>above).
That means DHCP has failed. It would have been very helpful if you had
provided that information back in the beginning.
>From there, I had to stop and restart my modem/router to get
>my wireless connection back (for a short period of time that is, if I
>have both ThinkPads running).
Again, sounds like a router (not modem, not ThinkPad) problem.
Alan
> by step, and report it fully here. See Mark's response for some of the
> more obvious things you're leaving out.
Will do that once I get my T42p's screen to work again: cannot do
anything right now.
> >> >Ok, I have googled around for a picture that looks like what I get:
> >> >http://www.itap.purdue.edu/airlink/images/vpnpc1a.jpg
> >> That helps a bit, but is just a start. Yourwirelessicon says "not
> >> connected". What do you see in "view availablewirelessnetworks"?
> You also seem to have a problem with your newsreader deleting spaces
> from quoted replies.
Using Google to post my messages from my partner's old laptop, since
mine has been rendered useless (screen issue mentioned above).
> >Most ofthen than not, my modem/router won't show up.
> Your "modem" won't ever show up.
I know. My D-Link DSL-G624T is a modem/router, hence my referring to
it in that way.
> Your router will show up if (a) it's broadcasting and (b) thewireless
> client is working. If it doesn't show up, then you have one and/or the
> other of those two problems.
>
> >I have to stop it
> >and restart it to see it listed again.
>
> That suggests your router is failing.
Yes, I gathered that much, but what I don't understand is why it only
seems to be failing when I use both ThinkPads, but not when I use
either ThinkPad with my partner's old non-ThinkPad laptop?
> >Other times, it will show up,
> >but I won't be able to connect to it.
> Different issue. Possible problems: interference, security gone wrong.
I have tried all sorts of settings, including no security at all, but
to no avail.
> >Again, by stopping it and
> >restarting it, it shows up and I will be able to connect to it.
> Again, points to a router problem. You may want to try a different
> router.
I have only the aforementioned modem/router. Also, as mentioned
before, it works fine with in some cases, namely one ThinkPad at a
time.
> >But,
> >as I have said several times, this will only be temporary if I have
> >bothThinkPadsrunning.
> Not surprising -- routers can have problems triggered by different types
> of loads. For example, many routers will fall over and die because of
> the huge number of connections opened by default settings in
> peer-to-peer filesharing apps.
We are not using any P2P softwares. We merely want to browse the
internet and check emails, both of which should require very little
load. Also, we do lose the connection when running both ThinkPads
*and* doing *nothing*, i.e. we just switch the laptops on, log on,
wait and... after a couple of minutes or so, we lose our internet
connection.
> >I have done all those things before (see my very second message). The
> >only thing I didn't mention (but did in the *other* thread I refer to
> >in my first message in *this* thread) is that everything works fine
> >when I use a wired connection. It is only when I try to connect
> >wirelessly that things start playing up.
> Sorry, but I'm _not_ going to chase down other threads. If you want my
> help, post the information in _this_ thread.
Which I have just done...
> >> >Otherwise, I am still of the view that there is an issue with the two
> >> >ThinkPads. Maybe it's hardware, maybe it's software, or maybe it's a
> >> >combination of the two (through their respective settings)?
> >> I think that view is almost certainly wrong. Onewirelessclient won't
> >> kill anotherwirelessclient (assuming it didn't kill thewireless
> >> router or access point).
> >I am only basing my 'conclusion' on what I am experiencing. ...
> You are actually leaping to conclusions. What I wrote is far more
> likely.
Which is?
> You would waste far less time if you just posted the requested
> information, instead of arguing about it.
I believe to have done so to the best of my ability, which I accept
may not be sufficient...
Alan
> >> WZC says "limited connection?"
> >> What?
> >seem), so what is that exactly?
> Connections?
I have tried to use both Windows XP wireless control and Access
Connections. In both cases, I got the same result: loss of connection.
> >Otherwise, I have indeed seen "limited
> >connection" and that was when I 'lost my connection' (i.e. all of the
> >above).
> That means DHCP has failed. It would have been very helpful if you had
> provided that information back in the beginning.
Ok, now we know that this is a helpful piece of information. How do I
go about fixing that now?
> >From there, I had to stop and restart my modem/router to get
> >mywirelessconnection back (for a short period of time that is, if I
> >have bothThinkPadsrunning).
> Again, sounds like a router (not modem, not ThinkPad) problem.
I am more than happy to accept that, no problem. Now, however, how do
you explain that my router only fails when both ThinkPads are running,
but not when only either of them is running?
Alan.
John Navas
<1171236167....@l53g2000cwa.googlegroups.com>:
>I have tried to use both Windows XP wireless control and Access
>Connections. In both cases, I got the same result: loss of connection.
Sorry, but I have no idea what "loss of connection" _exactly_ means.
Please stick to specific things, as Mark and I have suggested.
>> That means DHCP has failed. It would have been very helpful if you had
>> provided that information back in the beginning.
>
>Ok, now we know that this is a helpful piece of information. How do I
>go about fixing that now?
If you get your computer working again, what happens _exactly_ when you
click Repair in WZC?
>> Again, sounds like a router (not modem, not ThinkPad) problem.
>
>I am more than happy to accept that, no problem. Now, however, how do
>you explain that my router only fails when both ThinkPads are running,
>but not when only either of them is running?
Both together add enough load of a given kind that the router falls over
and dies. I think your best bet is to try a different router.
If you get your computer working again, try the FixDHCP script at
<http://wireless.wikia.com/wiki/Fast_Fixes_to_Wi-Fi_Problems#DHCP_isn.27t_working>
and post the _exact_ output here.
Alan
> >Connections. In both cases, I got the same result: loss of connection.
> Sorry, but I have no idea what "loss of connection" _exactly_ means.
> Please stick to specific things, as Mark and I have suggested.
Can't you accept that by 'loss of connection' I mean that the icon has
a red cross, that I have more often than not 'limited connection',
that I cannot browse the internet, cannot receive/send emails, cannot
ping anything, etc.? Do I have to spell it out every single time?
> >> That means DHCP has failed. It would have been very helpful if you had
> >> provided that information back in the beginning.
> >Ok, now we know that this is a helpful piece of information. How do I
> >go about fixing that now?
> If you get your computer working again, what happens _exactly_ when you
> click Repair in WZC?
I cannot recall the exact message I get, but that basically fails and
the only thing that works is for me to stop and restart my modem/
router.
> >> Again, sounds like a router (not modem, not ThinkPad) problem.
> >I am more than happy to accept that, no problem. Now, however, how do
> >you explain that my router only fails when bothThinkPadsare running,
> >but not when only either of them is running?
> Both together add enough load of a given kind that the router falls over
> and dies. I think your best bet is to try a different router.
You are not answering my question. I have both of my ThinkPads
running, none of them being used for any internet traffic at all, yet
within a couple of minutes or so, they will both lose their connection
(see my definition of that above). Now, if I have one ThinkPad running
only, I can do whatever I want with my internet connection, no problem
things will be working just fine, but as soon as I start using my
other ThinkPad, then both ThinkPads will lose their connection (again,
see my definition of that expression above). So, what kind of non-
Internet related load could get my two ThinkPads to lose their
connection?
> If you get your computer working again, try the FixDHCP script at
> <http://wireless.wikia.com/wiki/Fast_Fixes_to_Wi-Fi_Problems#DHCP_isn....>
> and post the _exact_ output here.
Will do that as soon as I can get my screen sorted out.
Jeff Liebermann
>Do I have to spell it out every single time?
I agree with John and Mark. You descriptions are somewhat difficult
to decode. However, you finally described the problem clearly in the
next paragraph.
>You are not answering my question. I have both of my ThinkPads
>running, none of them being used for any internet traffic at all, yet
>within a couple of minutes or so, they will both lose their connection
>(see my definition of that above). Now, if I have one ThinkPad running
>only, I can do whatever I want with my internet connection, no problem
>things will be working just fine, but as soon as I start using my
>other ThinkPad, then both ThinkPads will lose their connection (again,
>see my definition of that expression above). So, what kind of non-
>Internet related load could get my two ThinkPads to lose their
>connection?
Kinda sounds like a duplicated IP address. Let's do some diagnostics
and see what happens. On *BOTH* laptops, run:
Start -> run -> cmd <enter>
ipconfig /all | find "Address"
You should get something like:
C:> ipconfig /all | find "Address"
Physical Address. . . . . . . . . : 00-02-B3-1E-43-17
IP Address. . . . . . . . . . . . : 192.168.1.11
Both lines should be different on the two laptops.
If the Physical Address (MAC address) is the same, the two computers
were setup by cloning and have the same MAC address in the registry.
That won't work, but is also improbable as the T42p and X41 laptops
are quite different. Worth checking anyway as there are some
utilities that do the same thing.
If the MAC addresses are different, but the IP Address is the same,
then you have a static IP address setup on one or both machines which
will need to either change, or be converted to a more usable DHCP
assigned IP address.
That fact that a 3rd laptop works just fine (probably because it is
properly configured) leads me to suspect that the problem is in the
DSL-G624T and not in the laptops. Any chance you have more MAC
addresses configured in the filter than you have DHCP assigned IP
addresses available in the IP address pool?
Are you using a RADIUS server for authentication? Probably not as
you're using MAC filtering which is largely a waste of effort.
However, if you are using a RADIUS server, any chance that it has some
manner of authentication user limit?
It's also possible that the router is configured to only allow a
limited number of wireless connections, or some other form of
misconfigured security.
Can you plug the two laptops into the network using ethernet CAT5
cables instead of wireless? If so, do they co-exist?
There are some other obscure misconfigurations and combinations
possible, but let's check the easy stuff first.
--
Jeff Liebermann je...@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
John Navas
<je...@comix.santa-cruz.ca.us> wrote in
<q740t2d4korpuvrk3...@4ax.com>:
>"Alan" <aga...@gmail.com> hath wroth:
>>You are not answering my question. I have both of my ThinkPads
>>running, none of them being used for any internet traffic at all, yet
>>within a couple of minutes or so, they will both lose their connection
>>(see my definition of that above). Now, if I have one ThinkPad running
>>only, I can do whatever I want with my internet connection, no problem
>>things will be working just fine, but as soon as I start using my
>>other ThinkPad, then both ThinkPads will lose their connection (again,
>>see my definition of that expression above). So, what kind of non-
>>Internet related load could get my two ThinkPads to lose their
>>connection?
>
>Kinda sounds like a duplicated IP address.
Maybe, but then error messages should pop up. Alan?
jpd
On 2007-02-12, Jeff Liebermann <je...@comix.santa-cruz.ca.us> wrote:
> That fact that a 3rd laptop works just fine (probably because it is
> properly configured) leads me to suspect that the problem is in the
> DSL-G624T and not in the laptops. Any chance you have more MAC
> addresses configured in the filter than you have DHCP assigned IP
> addresses available in the IP address pool?
I have, on occasion, noticed that it is possible for some cheap consumer
excuses for routers like the one mentioned above to give out the same IP
twice to two very different machines[1], for no apparent reason and with
plenty of free addresses in the pool. Releasing and re-getting a lease
fixed that particular problem. (eg on windows: ipconfig /renew)
[snip: more possible causes of the problem]
> There are some other obscure misconfigurations and combinations
> possible, but let's check the easy stuff first.
And gather more information, of course. :-)
[1] With at least OS, cpu, board chipset, and network card manufacturers
being all different.
--
j p d (at) d s b (dot) t u d e l f t (dot) n l .
This message was originally posted on Usenet in plain text.
Any other representation, additions, or changes do not have my
consent and may be a violation of international copyright law.
John Navas
<1171262884....@k78g2000cwa.googlegroups.com>:
>> >I have tried to use both Windows XPwirelesscontrol and Access
>> >Connections. In both cases, I got the same result: loss of connection.
>> Sorry, but I have no idea what "loss of connection" _exactly_ means.
>> Please stick to specific things, as Mark and I have suggested.
>
>Can't you accept that by 'loss of connection' I mean that the icon has
>a red cross, that I have more often than not 'limited connection',
>that I cannot browse the internet, cannot receive/send emails, cannot
>ping anything, etc.? Do I have to spell it out every single time?
You do have to spell it out every single time, and do so precisely --
stuff like "more often than not" is not helpful -- red X (no connection)
and yellow exclamation mark (limited connection) cannot occur at the
same time! It's either one or the other, and different problems have
different symptoms, so I need to know the _exact_ symptoms.
>I cannot recall the exact message I get, but that basically fails and
>the only thing that works is for me to stop and restart my modem/
>router.
Again, not helpful -- I need to know the exact message.
>> Both together add enough load of a given kind that the router falls over
>> and dies. I think your best bet is to try a different router.
>
>You are not answering my question. ...
Sorry, I'm doing my best with the limited information you're providing.
Mark McIntyre
<aga...@gmail.com> wrote:
>> >I have tried to use both Windows XPwirelesscontrol and Access
>> >Connections. In both cases, I got the same result: loss of connection.
>> Sorry, but I have no idea what "loss of connection" _exactly_ means.
>> Please stick to specific things, as Mark and I have suggested.
>
>Can't you accept that by 'loss of connection' I mean that the icon has
>a red cross, that I have more often than not 'limited connection',
The difficulty for John and I is that Windows uses this tiny
notification to mean a large number of very different things.
Apparently Microsoft thought it would confuse users to actually tell
them the precise problem. So the red X by itself doesn't really tell
you very much.
>that I cannot browse the internet, cannot receive/send emails, cannot
>ping anything, etc.? Do I have to spell it out every single time?
Each time, you are trying something new. Perhaps we fixed one problem
and so something has changed about precisely how you cannot connect.
Therefore its useful to be as descriptive as possible each time.
>> Both together add enough load of a given kind that the router falls over
>> and dies. I think your best bet is to try a different router.
>
>You are not answering my question.
The answer is that possibly your router cannot take the load of two
laptops. This probably means the router is defective, and you need to
try a different unit.
An example: A couple of years ago, I had a problem where my laptop
randomly lost wireless connectivity. I discovered that it happened
whenever anyone tried to use the printserver built into the router -
the router was rebooting occasionally. With a different router a few
years before that, it all worked fine except if I did a lot of
downloading. Then the router crashed.
>So, what kind of non-
>Internet related load could get my two ThinkPads to lose their
>connection?
The common factor is that both Thinkpads connect to the router and
negotiate access to the internet through it. So try a different
router....
--
Mark McIntyre
Mark McIntyre
<aga...@gmail.com> wrote:
(John Navas wrote, replying to a comment from Alan)
>> >I have to stop it
>> >and restart it to see it listed again.
>>
>> That suggests your router is failing.
>
>Yes, I gathered that much, but what I don't understand is why it only
>seems to be failing when I use both ThinkPads, but not when I use
>either ThinkPad with my partner's old non-ThinkPad laptop?
See my comments elsethread on how retail routers can fall over without
any sensible reason.
Are all three laptops using 11G mode, or is one of them in 11B?
Did you try connecting the laptops up via network cables? If so, do
you get the same problems?
>I have only the aforementioned modem/router.
Can you borrow one from someone? Worst case, routers are cheap.
>Also, as mentioned
>before, it works fine with in some cases, namely one ThinkPad at a
>time.
What do the lights on the router do when you are having problems? Can
you watch them carefully? I'm not familiar with that particular
router, but I'd imagine it has LEDs for power, WAN conection, LAN
ports, and wireless.
>We are not using any P2P softwares.
John was just noting that retail routers can have all sorts of
problems and giving one example.
>We merely want to browse the
>internet and check emails, both of which should require very little
>load. Also, we do lose the connection when running both ThinkPads
>*and* doing *nothing*, i.e. we just switch the laptops on, log on,
>wait and... after a couple of minutes or so, we lose our internet
>connection.
Did you disable power-saving in both laptops, especially any settings
in Device Manager which allow the computer to turn off the device to
save power?
--
Mark McIntyre
Jeff Liebermann
>The difficulty for John and I is that Windows uses this tiny
>notification to mean a large number of very different things.
>Apparently Microsoft thought it would confuse users to actually tell
>them the precise problem. So the red X by itself doesn't really tell
>you very much.
Actually, Windoze does a truely horrible job of diagnostics. I the
case of WZC (wireless zero config), it's also WZD (wireless zero
diagnostics). There's no obvious indication at what stage of the
connection process, the connection has failed (driver, SSID detection,
SSID selection, AP association, encryption key exchange, DHCP,
filters, authentication, and application).
On the other end of the scale, WZC does have the ability to generate
diagnostic output.
<http://support.microsoft.com/kb/328601>
<http://www.microsoft.com/technet/prodtechnol/winxppro/maintain/wlansupp.mspx>
The problem is that it generates huge amounts of diagnostic output,
much of which is difficult to understand. Feast or famine, I guess.
The good news is that it was apparently designed for NDIS5 driver
debugging and has been very useful for convincing at least one
manufactory that their driver needs some more work.
IE7 also includes some diagnostics:
<http://www.microsoft.com/windowsxp/using/networking/expert/russel_diagnostics.mspx>
<http://support.microsoft.com/kb/326155/>
which have allowed some of my customer to perform amazing amounts of
damage and difficult to recover registry changes. My favorite
customer comment was "I fixed the problem, but nothing works".
Note that I'm not suggesting that Alan attempt to use these tools at
this point.
>The answer is that possibly your router cannot take the load of two
>laptops. This probably means the router is defective, and you need to
>try a different unit.
Good point. The Dlink DSL-G624T is a mystery to me because it's only
sold in the UK. I also don't like all in one modem-router-wireless
conglomerations because they are difficult to replace sub-systems. If
you search Google for "DSL-G624T problem", a substantial number of
hits and problems appear. A clue might be the list of maximum
wireless connections found at:
<http://www.smallnetbuilder.com/component/option,com_wrapper/Itemid,156/>
See chart under "Maximum Simultaneous Connections". The DSL-G624T is
not listed, but the chart does illustrate that there are some bottom
of the line products with some severe connection limitations. Since
we know that MAC address filtering is being used, my guess is that the
use of such ACL's tends to reduce most performance results.
>The common factor is that both Thinkpads connect to the router and
>negotiate access to the internet through it. So try a different
>router....
That would be too easy.
Alan
> >seems to be failing when I use both ThinkPads, but not when I use
> >either ThinkPad with my partner's old non-ThinkPad laptop?
> See my comments elsethread on how retail routers can fall over without
> any sensible reason.
Will do that.
> Are all three laptops using 11G mode, or is one of them in 11B?
The two ThinkPads use can handle both B and G modes, while the old
laptop can only handle B mode. The modem/router can support both B and
G modes.
> Did you try connecting the laptops up via network cables? If so, do
> you get the same problems?
I have tried that with both ThinkPads (one at a time) and the one
connected via a cable was working fine, while I cannot recall for the
one without a wire and, unfortunately, I won't be able to test before
several days: one of the ThinkPad's mother board has just died on me,
so it's on its way back to the manufacturer for repair... :(
> >I have only the aforementioned modem/router.
> Can you borrow one from someone? Worst case, routers are cheap.
I am not sure I can, not to mention that this is a combined modem/
router, which I recently bought after my old combined modem/router
died on me. Yes, that's what we call Murphy's law! :) or :( rather!
> >Also, as mentioned
> >before, it works fine with in some cases, namely one ThinkPad at a
> >time.
> What do the lights on the router do when you are having problems? Can
> you watch them carefully? I'm not familiar with that particular
> router, but I'd imagine it has LEDs for power, WAN conection, LAN
> ports, and wireless.
Will do that once I have got my other ThinkPad back.
> >We are not using any P2P softwares.
> John was just noting that retail routers can have all sorts of
> problems and giving one example.
Ok.
> >We merely want to browse the
> >internet and check emails, both of which should require very little
> >load. Also, we do lose the connection when running both ThinkPads
> >*and* doing *nothing*, i.e. we just switch the laptops on, log on,
> >wait and... after a couple of minutes or so, we lose our internet
> >connection.
> Did you disable power-saving in both laptops, especially any settings
> in Device Manager which allow the computer to turn off the device to
> save power?
I don't think I have, but that's a good point. I will check that.
Alan.
Alan
> I agree with John and Mark. You descriptions are somewhat difficult
> to decode. However, you finally described the problem clearly in the
> next paragraph.
Sorry, I guess I am just getting somewhat impatient after all the
problems I have been experiencing lately, the last one being my T42p's
mother board dying on me...
> >You are not answering my question. I have both of my ThinkPads
> >running, none of them being used for any internet traffic at all, yet
> >within a couple of minutes or so, they will both lose their connection
> >(see my definition of that above). Now, if I have one ThinkPad running
> >only, I can do whatever I want with my internet connection, no problem
> >things will be working just fine, but as soon as I start using my
> >other ThinkPad, then both ThinkPads will lose their connection (again,
> >see my definition of that expression above). So, what kind of non-
> >Internet related load could get my two ThinkPads to lose their
> >connection?
>
> Kinda sounds like a duplicated IP address. Let's do some diagnostics
> and see what happens. On *BOTH* laptops, run:
> Start -> run -> cmd <enter>
> ipconfig /all | find "Address"
> You should get something like:
> C:> ipconfig /all | find "Address"
> Physical Address. . . . . . . . . : 00-02-B3-1E-43-17
> IP Address. . . . . . . . . . . . : 192.168.1.11
> Both lines should be different on the two laptops.
Agreed and they are/were.
> If the Physical Address (MAC address) is the same, the two computers
> were setup by cloning and have the same MAC address in the registry.
> That won't work, but is also improbable as the T42p and X41 laptops
> are quite different. Worth checking anyway as there are some
> utilities that do the same thing.
I did, at some point, check their respective MAC address as I entered
them so that the DHCP server could assign the ThinkPads a unique IP
address.
> If the MAC addresses are different, but the IP Address is the same,
> then you have a static IP address setup on one or both machines which
> will need to either change, or be converted to a more usable DHCP
> assigned IP address.
I went through all of that and, as far as I can tell/remember,
everything was 'fine', yet...
> That fact that a 3rd laptop works just fine (probably because it is
> properly configured)
I have configured all three laptops myself and in the exact same way
(as far as I can recall).
> leads me to suspect that the problem is in the
> DSL-G624T and not in the laptops. Any chance you have more MAC
> addresses configured in the filter than you have DHCP assigned IP
> addresses available in the IP address pool?
How do you mean? I am not at home right now, but I believe to have
plenty of IP addresses (192.168.1.2 to 192.168.1.255, if I recall
correctly), while I can only set an IP address to 5 or 6 MAC
addresses.
> Are you using a RADIUS server for authentication? Probably not as
> you're using MAC filtering which is largely a waste of effort.
> However, if you are using a RADIUS server, any chance that it has some
> manner of authentication user limit?
I have heard of that kind of server, but I must confess that I have no
idea as what its purpose is. What is it? How do I find out whether I
use one or not?
> It's also possible that the router is configured to only allow a
> limited number of wireless connections, or some other form of
> misconfigured security.
Not sure about that, since I can use two laptops (as long as they are
not my two ThinkPads).
> Can you plug the two laptops into the network using ethernet CAT5
> cables instead of wireless? If so, do they co-exist?
I haven't tried that, but I should have indeed tried it. Will do so as
soon as I get my T42p back. Thanks for the suggestion!
> There are some other obscure misconfigurations and combinations
> possible, but let's check the easy stuff first.
I am sure it will turn out to be something trivial (as usual). Just a
bit of a pain at the moment, as I have got the feeling that I have
tried everything (well, not quite, since I didn't try both ThinkPads
connected to the router via a cable for instance).
Alan.
Alan
> >>You are not answering my question. I have both of my ThinkPads
> >>running, none of them being used for any internet traffic at all, yet
> >>within a couple of minutes or so, they will both lose their connection
> >>(see my definition of that above). Now, if I have one ThinkPad running
> >>only, I can do whatever I want with my internet connection, no problem
> >>things will be working just fine, but as soon as I start using my
> >>other ThinkPad, then both ThinkPads will lose their connection (again,
> >>see my definition of that expression above). So, what kind of non-
> >>Internet related load could get my two ThinkPads to lose their
> >>connection?
>
> >Kinda sounds like a duplicated IP address.
>
> Maybe, but then error messages should pop up. Alan?
None poped up. I recall checking the IP address of each ThinkPad and
they were definitely different indeed.
Alan.
Alan
Fair enough. I am not a network specialist, so maybe I take certain
things for granted while I shouldn't. Anyway, my T42p is gone for
repair, so I guess we will have to postpone until I get it back...
Once I have it back, I will go through all your messages again and try
to get back to you all with more precise information... Until then,
thanks for your patience and suggestions...
Alan.
Jeff Liebermann
>Sorry, I guess I am just getting somewhat impatient after all the
>problems I have been experiencing lately, the last one being my T42p's
>mother board dying on me...
Karma problem. Such failures don't happen by themselves. I suggest
performing some good deeds to recharge your karma. For extreme cases,
a burnt offering of an old motherboard might be advisable.
>> Both lines should be different on the two laptops.
>Agreed and they are/were.
You're sure? I was hopeing that you could supply the actual IP
addresses. I've seen some rather bizarre junk appear on the IP line
(such as 3.0.0.0 which I never could explain). Also, 169.254.xxx.xxx
usually means that DHCP has failed. Instead of your conclusions,
could I just have the IP numbers? (Hint: I like numbers).
>I did, at some point, check their respective MAC address as I entered
>them so that the DHCP server could assign the ThinkPads a unique IP
>address.
Good enough. No need to supply those. Unfortunatly, that eliminates
the most obvious cause of the conflict.
>> If the MAC addresses are different, but the IP Address is the same,
>> then you have a static IP address setup on one or both machines which
>> will need to either change, or be converted to a more usable DHCP
>> assigned IP address.
>
>I went through all of that and, as far as I can tell/remember,
>everything was 'fine', yet...
Again, you're asking me to take your word for it. I believe you but
the output I asked for would be more interesting in checking
assumptions.
>> That fact that a 3rd laptop works just fine (probably because it is
>> properly configured)
>
>I have configured all three laptops myself and in the exact same way
>(as far as I can recall).
That may have been true when you initially configured the laptops, but
many not be true after you've been operating it for a while. Windoze
has the irritating habit of making changes during updates as do
various "utility" programs.
>> leads me to suspect that the problem is in the
>> DSL-G624T and not in the laptops. Any chance you have more MAC
>> addresses configured in the filter than you have DHCP assigned IP
>> addresses available in the IP address pool?
>
>How do you mean? I am not at home right now, but I believe to have
>plenty of IP addresses (192.168.1.2 to 192.168.1.255, if I recall
>correctly), while I can only set an IP address to 5 or 6 MAC
>addresses.
Problem. You should not be using "static DHCP" to assign IP addresses
in the middle of the DHCP IP address range. The DHCP range of
192.168.1.2 thru 254 (255 is the broadcast address), is excessive. I
suggest you reduce the range to .100 thru .149 (50 addresses). Use IP
addresess outside of this range for your static DHCP assigned IP's.
>> Are you using a RADIUS server for authentication? Probably not as
>> you're using MAC filtering which is largely a waste of effort.
>> However, if you are using a RADIUS server, any chance that it has some
>> manner of authentication user limit?
>
>I have heard of that kind of server, but I must confess that I have no
>idea as what its purpose is. What is it? How do I find out whether I
>use one or not?
You're not using a RADIUS server. For wireless a RADIUS server
provides a login and password for each user of the system. It
provides authentication via 802.1x protocol. The big advantage for
wireless is that it provides a unique WPA encryption key for each
session and for each user. There is no system wide shared WPA-PSK key
that can be leaked to the world. Each session has its own temporary
key which does not get re-used. If you want real wireless security,
this is the way to get it.
>> It's also possible that the router is configured to only allow a
>> limited number of wireless connections, or some other form of
>> misconfigured security.
>
>Not sure about that, since I can use two laptops (as long as they are
>not my two ThinkPads).
True. Some brilliant security experts advise limiting the number of
connections and DHCP assigned IP addresses to the number of known
users. This way, a hacker would be unlikely to obtain a DHCP assigned
address. Dumb idea, but it keeps appearing. Also, some routers have
an assignable connection limit. I can't tell if the DSL-G624T has
such a feature because the online emulators at:
<http://support.dlink.com/emulators/>
do not include this model.
The DSL-G604T might be close:
<http://support.dlink.com/Emulators/dslg604t/home_dhcp.html>
Change the DHCP range here to .100 thru .149.
Static DHCP or "reserved IP addresses" go here:
<http://support.dlink.com/Emulators/dslg604t/adv_lanclients.html>
>> Can you plug the two laptops into the network using ethernet CAT5
>> cables instead of wireless? If so, do they co-exist?
>
>I haven't tried that, but I should have indeed tried it. Will do so as
>soon as I get my T42p back. Thanks for the suggestion!
If it works, then there's something different about the way the IP
addresses are setup in the ethernet and wireless interfaces.
Unfortunately, it doesn't show what is different.
>> There are some other obscure misconfigurations and combinations
>> possible, but let's check the easy stuff first.
>
>I am sure it will turn out to be something trivial (as usual).
Maybe. It's more common that it's some incorrect assumption. That
which is most obviously correct, beyond any need of checking, is the
problem. In this case, you have setup your DSL-G624T in a rather
complex manner. Not unusually complex, just complex. I think the
best approach would be to start over with the big reset button. Turn
off ALL security, filters, static DHCP, authentication, and
encryption. Start with getting it working with a ethernet connection.
Then go to an unencrypted wireless connection. At this point, check
for multiple laptop functionality. Only after it's working *AND
TESTED* in this basic form, do you turn on encryption, MAC filters,
static DHCP, and whatever else you have enabled (that you haven't
mentioned).
>Just a
>bit of a pain at the moment, as I have got the feeling that I have
>tried everything (well, not quite, since I didn't try both ThinkPads
>connected to the router via a cable for instance).
It might also be a weird router. Considering the quantity of hardware
that has blown up, it's highly probably that the DSL-G624T might be
blown or had its firmware mangled. If you do the reset to defaults I
suggested, this might also be a good time to also reload the firmware.
>Alan.
Alan
> >Agreed and they are/were.
> You're sure? I was hopeing that you could supply the actual IP
> addresses. I've seen some rather bizarre junk appear on the IP line
> (such as 3.0.0.0 which I never could explain). Also, 169.254.xxx.xxx
> usually means that DHCP has failed. Instead of your conclusions,
> could I just have the IP numbers? (Hint: I like numbers).
When I used DHCP with assigned IP address based on MAC address, I
would use 192.168.1.13 and 192.168.1.15 for the ThinkPads. I would use
the same addresses when not using DHCP and therefore hard-coding the
IP addresses in the TCP/IP settings. When using DHCP without any MAC
address lookup, the ThinkPads would get a different IP address such as
192.168.1.2, 192.168.1.3 or 192.168.1.4, depending on how many laptops
were online.
> >> If the MAC addresses are different, but the IP Address is the same,
> >> then you have a static IP address setup on one or both machines which
> >> will need to either change, or be converted to a more usable DHCP
> >> assigned IP address.
> >I went through all of that and, as far as I can tell/remember,
> >everything was 'fine', yet...
> Again, you're asking me to take your word for it. I believe you but
> the output I asked for would be more interesting in checking
> assumptions.
Agreed.
> >> That fact that a 3rd laptop works just fine (probably because it is
> >> properly configured)
> >I have configured all three laptops myself and in the exact same way
> >(as far as I can recall).
> That may have been true when you initially configured the laptops, but
> many not be true after you've been operating it for a while. Windoze
> has the irritating habit of making changes during updates as do
> various "utility" programs.
Once I got my ThinkPad back, I will double check all laptops' settings
and post that here, so that you guys have a clear idea as what I have
done. Might be the easiest way to get things sorted out indeed.
> >> leads me to suspect that the problem is in the
> >> DSL-G624T and not in the laptops. Any chance you have more MAC
> >> addresses configured in the filter than you have DHCP assigned IP
> >> addresses available in the IP address pool?
> >How do you mean? I am not at home right now, but I believe to have
> >plenty of IP addresses (192.168.1.2 to 192.168.1.255, if I recall
> >correctly), while I can only set an IP address to 5 or 6 MAC
> >addresses.
> Problem. You should not be using "static DHCP" to assign IP addresses
> in the middle of the DHCP IP address range. The DHCP range of
> 192.168.1.2 thru 254 (255 is the broadcast address), is excessive. I
> suggest you reduce the range to .100 thru .149 (50 addresses). Use IP
> addresess outside of this range for your static DHCP assigned IP's.
Ok, I didn't know about that. Will definitely keep that in mind.
Thanks!
> >> Are you using a RADIUS server for authentication? Probably not as
> >> you're using MAC filtering which is largely a waste of effort.
> >> However, if you are using a RADIUS server, any chance that it has some
> >> manner of authentication user limit?
> >I have heard of that kind of server, but I must confess that I have no
> >idea as what its purpose is. What is it? How do I find out whether I
> >use one or not?
> You're not using a RADIUS server. Forwirelessa RADIUS server
> provides a login and password for each user of the system. It
> provides authentication via 802.1x protocol. The big advantage forwirelessis that it provides a unique WPA encryption key for each
> session and for each user. There is no system wide shared WPA-PSK key
> that can be leaked to the world. Each session has its own temporary
> key which does not get re-used. If you want realwirelesssecurity,
> this is the way to get it.
Ok, I am indeed definitely not using that. Since this is a home
network, I don't think I need to go to that extent to secure my
network.
> >> It's also possible that the router is configured to only allow a
> >> limited number ofwirelessconnections, or some other form of
> >> misconfigured security.
> >Not sure about that, since I can use two laptops (as long as they are
> >not my two ThinkPads).
> True. Some brilliant security experts advise limiting the number of
> connections and DHCP assigned IP addresses to the number of known
> users. This way, a hacker would be unlikely to obtain a DHCP assigned
> address. Dumb idea, but it keeps appearing. Also, some routers have
> an assignable connection limit. I can't tell if the DSL-G624T has
> such a feature because the online emulators at:
> <http://support.dlink.com/emulators/>
> do not include this model.
Ok, I will double check that...
> The DSL-G604T might be close:
It does indeed look very much like what I have.
> <http://support.dlink.com/Emulators/dslg604t/home_dhcp.html>
> Change the DHCP range here to .100 thru .149.
Ok, will do that.
> Static DHCP or "reserved IP addresses" go here:
> <http://support.dlink.com/Emulators/dslg604t/adv_lanclients.html>
I must confess that I have never 'played' with that page, but instead
set the static IP addresses under <http://support.dlink.com/Emulators/
dslg604t/home_dhcp.html>. Isn't that good enough?
> >> Can you plug the two laptops into the network using ethernet CAT5
> >> cables instead ofwireless? If so, do they co-exist?
> >I haven't tried that, but I should have indeed tried it. Will do so as
> >soon as I get myT42pback. Thanks for the suggestion!
> If it works, then there's something different about the way the IP
> addresses are setup in the ethernet andwirelessinterfaces.
> Unfortunately, it doesn't show what is different.
At least, it ought to narrow the problem.
> >> There are some other obscure misconfigurations and combinations
> >> possible, but let's check the easy stuff first.
> >I am sure it will turn out to be something trivial (as usual).
> Maybe. It's more common that it's some incorrect assumption. That
> which is most obviously correct, beyond any need of checking, is the
> problem. In this case, you have setup your DSL-G624T in a rather
> complex manner. Not unusually complex, just complex. I think the
> best approach would be to start over with the big reset button. Turn
> off ALL security, filters, static DHCP, authentication, and
> encryption.
I believe to have done that (several times even), but again whenever I
have both ThinkPads on then things stop working (whatever I mean by
that, since I cannot from the top of my head give you an exact
description of what went wrong). I will, however, try it all over
again, no problem.
> Start with getting it working with a ethernet connection.
> Then go to an unencryptedwirelessconnection. At this point, check
> for multiple laptop functionality. Only after it's working *AND
> TESTED* in this basic form, do you turn on encryption, MAC filters,
> static DHCP, and whatever else you have enabled (that you haven't
> mentioned).
Yes, that all seems very logical and sensible to me, and I believe to
have done exactly that, but I may have messed up something along the
way, so will definitely try again.
> >Just a
> >bit of a pain at the moment, as I have got the feeling that I have
> >tried everything (well, not quite, since I didn't try both ThinkPads
> >connected to the router via a cable for instance).
> It might also be a weird router. Considering the quantity of hardware
> that has blown up, it's highly probably that the DSL-G624T might be
> blown or had its firmware mangled. If you do the reset to defaults I
> suggested, this might also be a good time to also reload the firmware.
I did reload the firmware at some point, but I am not 100% surer as
whether I reset the settings to their factory ones. Will do that.
Alan.
Jeff Liebermann
>> Problem. You should not be using "static DHCP" to assign IP addresses
>> in the middle of the DHCP IP address range. The DHCP range of
>> 192.168.1.2 thru 254 (255 is the broadcast address), is excessive. I
>> suggest you reduce the range to .100 thru .149 (50 addresses). Use IP
>> addresess outside of this range for your static DHCP assigned IP's.
>
>Ok, I didn't know about that. Will definitely keep that in mind.
>Thanks!
It's usually not fatal. The DHCP server in your wireless router is
suppose to try and ping the IP address before it assigns it to some
other client. On the better routers, it's also suppose to sniff the
traffic looking for the corresponding MAC address. However, the
bottom of the line routers often don't bother or the client has ICMP
ping turned off where it doesn't respond. The chances of assigning
duplicate IP addresses is small but still possible.
>> Static DHCP or "reserved IP addresses" go here:
>> <http://support.dlink.com/Emulators/dslg604t/adv_lanclients.html>
>
>I must confess that I have never 'played' with that page, but instead
>set the static IP addresses under <http://support.dlink.com/Emulators/
>dslg604t/home_dhcp.html>. Isn't that good enough?
Yes. That appears to be the same thing for setting "static DHCP" or
"pre-assigned DHCP" IP addresses. Note that these IP addresses
*might* need to be inside the DHCP assignable range. Some routers
will accept any old IP address while others insist that it be inside
the DHCP range. It doesn't really matter because the router will know
not to re-assign it to another MAC address.
>> If it works, then there's something different about the way the IP
>> addresses are setup in the ethernet andwirelessinterfaces.
>> Unfortunately, it doesn't show what is different.
>
>At least, it ought to narrow the problem.
It's a clue. The real troubleshooting will probably require that we
determine which device or driver initiated the disconnect and why. I
was hopeing for something simple on the MAC or IP layers, but it
appears that it's something more subtle. My current best guess is
that there's something fundamentally wrong with the DSL-G624T or its
firmware.
>> Start with getting it working with a ethernet connection.
>> Then go to an unencryptedwirelessconnection. At this point, check
>> for multiple laptop functionality. Only after it's working *AND
>> TESTED* in this basic form, do you turn on encryption, MAC filters,
>> static DHCP, and whatever else you have enabled (that you haven't
>> mentioned).
>
>Yes, that all seems very logical and sensible to me, and I believe to
>have done exactly that, but I may have messed up something along the
>way, so will definitely try again.
Actually, it's more like desperation. I can't contrive any mechanism
(other than duplicate MAC and IP addresses) that would cause such a
failure. It's far too exotic and uncommon. Frankly, I'm out of
brilliant ideas and am resorting to changing things to see what
happens. It appears that you've done most everything correctly,
although not particularly systematically. My only really useful clue
is that other equipment at your site has also recently failed.
The basic assumption is that it will work with the DSL-G624T in the
default configuration (except for the DSL ISP settings). Same with
the default settings on the laptops (DHCP assigned IP's). If that
fails, don't bother going any furthur. Try re-flashing your firmware,
do another reset, try once more, and if the results are the same, go
buy a different router (this time with a seperate DSL modem).
>I did reload the firmware at some point, but I am not 100% surer as
>whether I reset the settings to their factory ones. Will do that.
The reset to defaults is important. If the firmware is scrambled, the
area in NVRAM where the settings are stored also might be scrambled.