Re: [BisManLUG] ubuntu server network fail (Solved)
James Grossmann
and everything is working correctly, I believe it was a multi-path
issue, I guess I have gotten used to the network-manager type of
connection management. I mentioned earlier that I had the two nics
connected to different switches, therefore, the best bonding I could
do was active-backup, which is plenty for my setup. Bonding is very
interesting, sadly, if you only read wikipedia on it, you get very
little of the story, and it seems that most people (including the
ubuntu wiki) quote wikipedia... For more info:
http://www.linuxfoundation.org/collaborate/workgroups/networking/bonding
which speaks about the arp issues, etc. very nice!
Full Speed Ahead! :)
Thanks for everyone's help!
James
On Tue, Jul 20, 2010 at 8:22 AM, Dan Falconer <dan.fa...@gmail.com> wrote:
> I would suggest unplugging/disabling all interfaces but the one you want to
> troubleshoot (eth1); eliminating extra interfaces eliminates extra
> variables. Once you're down to just that interface, work on it from there.
> The SSH problem might be a DNS issue: if there's no local domain, or no
> entry for the connecting IP, the destination SSH server will wait for DNS to
> timeout before proceeding.
>
> I would guess the update issues are caused by having two cards. If one is
> sending the response and the other is receiving, something might be getting
> routed wrong. One other thing to check is to make sure that the MAC
> addresses are not the same; if at some point you did something to clone the
> MAC of another card for any reason, the network is the part that's really
> confused: it will have some "ARP" cache or something like that that's
> causing traffic to go... wonky. I read somewhere something about NMAP
> fixing such network issues, so you may want to google for that (it may have
> been something posted on the LUG too).
>
> On Mon, Jul 19, 2010 at 5:29 PM, Collin Scull <col...@grizella.com> wrote:
>>
>> It might be caused by having two interfaces on the same 192.168.1.0/24
>> subnet. I have had similar issues when I connect using wireless and wired at
>> the same time in the office or I leave my office vpn on when I come in. In
>> both cases I have multiple routes to the same subnet and packets going in on
>> one interface have responses going out on the other interface.
>>
>> Collin
>>
>> On 7/19/2010 4:33 PM, James Grossmann wrote:
>>>
>>> Interesting thing to note I ran an ifconfig, and note that the gigabit
>>> device is eth1, getting virtually no traffic... I did replace the
>>> cable, no difference...
>>>
>>> ifconfig -a
>>> eth0 Link encap:Ethernet HWaddr xx:xx:xx:xx:xx:xx
>>> inet addr:192.168.1.7 Bcast:192.168.1.255 Mask:255.255.255.0
>>> UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
>>> RX packets:55927713 errors:0 dropped:0 overruns:0 frame:0
>>> TX packets:61424990 errors:0 dropped:0 overruns:0 carrier:0
>>> collisions:0 txqueuelen:1000
>>> RX bytes:1447437214 (1.4 GB) TX bytes:3170178790 (3.1 GB)
>>> Interrupt:23 Base address:0x2000
>>>
>>> eth1 Link encap:Ethernet HWaddr xx:xx:xx:xx:xx:xx
>>> inet addr:192.168.1.1 Bcast:192.168.1.255 Mask:255.255.255.0
>>> UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
>>> RX packets:40386 errors:0 dropped:0 overruns:0 frame:0
>>> TX packets:3956 errors:0 dropped:0 overruns:0 carrier:0
>>> collisions:0 txqueuelen:1000
>>> RX bytes:13980573 (13.9 MB) TX bytes:485676 (485.6 KB)
>>>
>>> lo Link encap:Local Loopback
>>> inet addr:127.0.0.1 Mask:255.0.0.0
>>> UP LOOPBACK RUNNING MTU:16436 Metric:1
>>> RX packets:8092 errors:0 dropped:0 overruns:0 frame:0
>>> TX packets:8092 errors:0 dropped:0 overruns:0 carrier:0
>>> collisions:0 txqueuelen:0
>>> RX bytes:4139514 (4.1 MB) TX bytes:4139514 (4.1 MB)
>>>
>>>
>>> On Mon, Jul 19, 2010 at 4:19 PM, James Grossmann<cct...@gmail.com>
>>> wrote:
>>>
>>>>
>>>> The interfaces file is part of my server, the nat/firewall is all
>>>> being taken care of by the linksys dd-wrt router, to which I have only
>>>> the broadband and a connection to the gigabit switch connected, it is
>>>> supplying a static dhcp to each mac address. From the gigabit switch
>>>> I have connected my desktop, the gigabit nic in the server and the
>>>> cisco 100mbit switch. I have the 2nd (original) nic in the server
>>>> attached to the cisco switch.
>>>> I am not certain that I have IP masquerading going, I think I do
>>>> through my router, but it's been a while since I set it up, I thought
>>>> that was for if I wanted to use my computer as a router, which I am
>>>> not doing. I have been using the router to assign internal ips
>>>> (192.168.1.x) for a couple of years now, with no problems. The IP
>>>> from my supplier is dynamic and I have been using DHCP, so I'm not in
>>>> problems there.
>>>> What I changed mainly was that I installed the cisco switch
>>>> (connecting a couple things to it) and added the gigabit nic to the
>>>> server (specifying the old ip to that nic), other than that, the
>>>> system has been working fine as it is for years now. I just wanted a
>>>> bit more speed...
>>>> Thanks,
>>>> James
>>>>
>>>> On Mon, Jul 19, 2010 at 3:36 PM, Eric Wanchic<ewan...@qwest.net>
>>>> wrote:
>>>>
>>>>>
>>>>> I second, that might be the easiest. Do you have a tester?
>>>>>
>>>>> Assuming that is not the problem, sorry, I might be a little lost in
>>>>> translation. I have a couple of questions unanswered, but yet assuming
>>>>> everything worked before....
>>>>>
>>>>> Is the interfaces file you referenced part of an ubuntu firewall/NAT?
>>>>> by the
>>>>> looks of it, it should get a random IP from the Cable (I'll call
>>>>> connection
>>>>> A) and a random IP from the DHCP (from the Wireless DHCP, I call B),
>>>>> yet...that means that the gateway could be random, unless you force
>>>>> connection B an IP based on MAC address. For me, I have DHCP on the
>>>>> same
>>>>> firewall/NAT box.
>>>>>
>>>>> Plus, if I have the network setup correct, do you have IP masquerading
>>>>> enabled? If not, that will prevent you from getting out into the
>>>>> Internet.
>>>>>
>>>>> Finally, I assume you do have a DHCP with your cable supplier, or is it
>>>>> a
>>>>> STATIC IP. If it is Static, you might have reset some things and you'll
>>>>> have
>>>>> to call their tech support and ask them to "Press the Button" Not
>>>>> joking.
>>>>> This is what fixes it, and then you'll need to change interfaces to
>>>>> that it
>>>>> is a static IP, of course.
>>>>>
>>>>> I hope this helps, but again I'm a little lost too :)
>>>>>
>>>>> Eric
>>>>>
>>>>>
>>>>>
>>>>> On 07/19/2010 03:19 PM, Matthew Lengenfelder wrote:
>>>>>
>>>>> I'd bet on it being a bad cable that can't quite handle the gigabit
>>>>> speeds.
>>>>> and/or the cable that is being used for the cable modem (if the errors
>>>>> are
>>>>> only happening with traffic outside of your network).
>>>>>
>>>>>
>>>>> On Mon, Jul 19, 2010 at 3:09 PM, James Grossmann<cct...@gmail.com>
>>>>> wrote:
>>>>>
>>>>>>
>>>>>> I'm looking to reconfigure the network on my server system, I moved it
>>>>>> to a new home, in a rack mount case and added a gigabit nic to it (the
>>>>>> motherboard only has 100mbit). However, since the move, I've been
>>>>>> having network problems, it takes me 30 sec to 1 min to get the
>>>>>> password request when I ssh into it. It has been failing at a number
>>>>>> of updates off of the internet--gentoo portage sync and
>>>>>> mythfilldatabase are the ones I've noticed so far-- and when I ping
>>>>>> the external net, I get nothing, not even a response as though it
>>>>>> attempted to ping (ie. how many tries and fails, etc.), either with ip
>>>>>> address or a domain name. I note that dns resolution doesn't seem to
>>>>>> be too good internally either, when I ping a local host (my desktop),
>>>>>> I get the same result, however, when I ping an ip address internally,
>>>>>> it works fine. I'm using my wrt54gs to do dhcp, and I did do
>>>>>> something perhaps out of the ordinary, I assigned the new nic to the
>>>>>> old address of the server, reassigning the old nic to a different
>>>>>> address... After installing the system into the new case, I added the
>>>>>> eth1 (gigabit) to /etc/network/interfaces, which now looks like this:
>>>>>>
>>>>>> # This file describes the network interfaces available on your system
>>>>>> # and how to activate them. For more information, see interfaces(5).
>>>>>>
>>>>>> # The loopback network interface
>>>>>> auto lo
>>>>>> iface lo inet loopback
>>>>>>
>>>>>> # The primary network interface
>>>>>> auto eth0
>>>>>> iface eth0 inet dhcp
>>>>>>
>>>>>> auto eth1
>>>>>> iface eth1 inet dhcp
>>>>>>
>>>>>> If it were Gentoo, I'd be rocking already, and in some ways I am, I
>>>>>> can do transfers across the gigabit segment of my net at great speed,
>>>>>> even with this problem, but I would really prefer things to work
>>>>>> correctly. I'm just not as comfortable with the ubuntu-server network
>>>>>> setup as I am with Gentoo.
>>>>>> Thanks in advance,
>>>>>>
>>>>>> James
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>
>
>
>
> --
> Best Regards,
>
>
> Dan Falconer
> http://www.CrazedSanity.com || http://www.Buzzkill.org
>