Solaris 10 and MTU?
Norbert Möndjen
I am running solaris in vmware bridged networking. Is there a possibility to
set the MTU permanent? I mean I can do somewhere in the startup-scripts
a ifconfig e1000g0 mtu 1492, but I think that there should be somewhere a
config-file for it.
Can somebody tell me where and how to?
Ciao Nobbe
Oscar del Rio
> I am running solaris in vmware bridged networking. Is there a possibility to
> set the MTU permanent? I mean I can do somewhere in the startup-scripts
> a ifconfig e1000g0 mtu 1492, but I think that there should be somewhere a
> config-file for it.
add it to /etc/hostname.e1000g0. e.g.
hostname mtu 1492
the single line is fed to "ifconfig" during startup.
Norbert Möndjen
Thanks, I give it a try.
Ciao Nobbe
Norbert Möndjen
Does it work with dhcp too?
In my /etc/hostname.e1000g0 is the following line:
inet nosolstd mtu 1492
And the mtu setting is ignored, still having a mtu of 1500
Ciao nobbe
Oscar del Rio
> Oscar del Rio wrote:
>
>> Norbert Möndjen wrote:
>>> I am running solaris in vmware bridged networking. Is there a possibility
>>> to set the MTU permanent? I mean I can do somewhere in the
>>> startup-scripts a ifconfig e1000g0 mtu 1492, but I think that there
>>> should be somewhere a config-file for it.
>> add it to /etc/hostname.e1000g0. e.g.
>> hostname mtu 1492
>> the single line is fed to "ifconfig" during startup.
>
> Does it work with dhcp too?
>
> In my /etc/hostname.e1000g0 is the following line:
> inet nosolstd mtu 1492
What I described is for static IP. The "inet" keyword is redundant, the start-up
scripts use something like (*oversimplified!*) [1]
/sbin/ifconfig $iface inet `cat /etc/hostname.$iface`
For dhcp, I believe the config file is /etc/dhcp.$primary which is parsed more
or less like
/sbin/ifconfig $primary auto-dhcp primary `cat /etc/dhcp.$primary`
but I don't know if you can add mtu in there or if the DHCP server is supposed
to give you the proper mtu.
[1] See the scripts in /lib/svc: method/net-physical & share/net_include.sh
Guolong
set mtu in hostname.e1000g0. But mtu setting is ignored.
Any idea for this problem please?
Ian Collins
> I'm working on same problem :
> set mtu in hostname.e1000g0. But mtu setting is ignored.
> Any idea for this problem please?
>
Allowed values are:
0 Standard ethernet frames with a MTU equal to
1500. Default.
1 Jumbo frames with a maximum MTU of 4096.
2 Jumbo frames with a maximum MTU of 8192.
3 Jumbo frames with a maximum MTU of 16384.
--
Ian Collins
Gary R. Schmidt
-bash-3.00$ sudo ifconfig -a
e1000g0: flags=1001000843<UP,BROADCAST,RUNNING,MULTICAST,IPv4,FIXEDMTU>
mtu 1492 index 2
inet a.b.c.d netmask ffffff00 broadcast a.b.c.255
ether ...
-bash-3.00$ cat /etc/hostname.e1000g0
paranoia
mtu 1492
up
Cheers,
Gary B-)
--
______________________________________________________________________________
Armful of chairs: Something some people would not know
whether you were up them with or not
- Barry Humphries
Rick Jones
> Ian Collins wrote:
> > Guolong wrote:
> >> I'm working on same problem :
> >> set mtu in hostname.e1000g0. But mtu setting is ignored.
> >> Any idea for this problem please?
> >>
> > According to the e1000g0 man page (have you checked?)
> >
> > Allowed values are:
> >
> > 0 Standard ethernet frames with a MTU equal to
> > 1500. Default.
> > 1 Jumbo frames with a maximum MTU of 4096.
> > 2 Jumbo frames with a maximum MTU of 8192.
> > 3 Jumbo frames with a maximum MTU of 16384.
> >
> Hmmm... (S10, U5)
> -bash-3.00$ sudo ifconfig -a
> e1000g0: flags=1001000843<UP,BROADCAST,RUNNING,MULTICAST,IPv4,FIXEDMTU>
> mtu 1492 index 2
> inet a.b.c.d netmask ffffff00 broadcast a.b.c.255
> ether ...
> -bash-3.00$ cat /etc/hostname.e1000g0
> paranoia
> mtu 1492
> up
Differences perhaps between the driver/NIC limits set via ndd settings
and the values used in ifconfig?
rick jones
--
The glass is neither half-empty nor half-full. The glass has a leak.
The real question is "Can it be patched?"
these opinions are mine, all mine; HP might not want them anyway... :)
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...
Guolong
> Guolong wrote:
> > I'm working on same problem :
> > set mtu in hostname.e1000g0. But mtu setting is ignored.
> > Any idea for this problem please?
>
> According to the e1000g0 man page (have you checked?)
>
> Allowed values are:
>
> 0 Standard ethernet frames with a MTU equal to
> 1500. Default.
>
>
> 2 Jumboframes with a maximum MTU of 8192.
>
> 3 Jumboframes with a maximum MTU of 16384.
>
> --
> Ian Collins
Allowed valued (1,2) is ok. But value 3(MTU 16384) can NOT work for
Solaris 10 e1000 driver.
It's a known bug of e1000 driver which has not been fixed in Solaris
10/U6. It has been confirmed with Sun engineer....
That means you can not set mtu size to 9000 which is default jumbo
frame size in many cases.
Now I'm worry whether two server with different mtu size (e.g. 9000
and 8000) could access each other through switch?
Eddie
the MTU to 9000. We had to force the MTU on each interface as it
defaulted to 9000 after that in the /etc/hostname.e1000g# file. Hope
this helps someone out:
edit /kernel/drv/e1000g.conf
* #MaxFrameSize=0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0;
* MaxFrameSize? =3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,0;
netstat -in:
Name Mtu Net/Dest Address Ipkts Ierrs Opkts Oerrs
Collis Queue
lo0 8232 127.0.0.0 127.0.0.1 35064204 0 35064204 0
0 0
e1000g0 1500 10.130.111.0 10.130.111.10 1427957 0 1740015 0
0 0
e1000g1 1500 192.168.111.0 192.168.111.10 435094780 0 403594505
0 0 0
e1000g2 1500 10.130.11.0 10.130.11.10 553980791 0 497821577
0 0 0
e1000g3 9000 10.130.9.0 10.130.9.8 1110159144 0 1470248904
0 0 0
ifconfig:
e1000g3:
flags=1001000843<UP,BROADCAST,RUNNING,MULTICAST,IPv4,FIXEDMTU> mtu
9000 index 5
inet 10.130.9.8 netmask ffffff00 broadcast 10.130.9.255
groupname filergroup
/etc/hostname.e1000g3
10.130.9.8 netmask + broadcast + group filergroup mtu 9000 up
uname -a:
SunOS xxxxxxx 5.10 Generic_127127-11 sun4v sparc SUNW,Sun-Blade-T6300
Rick Jones
> Now I'm worry whether two server with different mtu size (e.g. 9000
> and 8000) could access each other through switch?
If the switch supports and is configured for a frame size compatible
with the larger MTU
If _all_ the communications between the systems is TCP
Then, you can mix and match the MTUs.
However, if some of the comms are UDP or something without a size
exchange in it then you can have unpleasant connectivity black holes
when a larger MTU system tries to send data to a smaller MTU system in
the same broadcast domain.
rick jones
--
denial, anger, bargaining, depression, acceptance, rebirth...
where do you want to be today?
Guolong
Description for this e1000g bug:
We are testing S10U6B5 e1000g driver with SPARC Enterprise T5220.
And we've found if "MaxFrameSize" is set to "e1000g.conf" as 4k/8k/
16k,
the mtu value is set as follows respectively.
# dladm show-link
e1000g0 type: non-vlan mtu: 1500 device: e1000g0 <-
normal
e1000g1 type: non-vlan mtu: 4072 device: e1000g1 <- 4k
e1000g2 type: non-vlan mtu: 8168 device: e1000g2 <- 8k
e1000g3 type: non-vlan mtu: 8978 device: e1000g3 <- 16k
e1000g.conf:
MaxFrameSize=0,1,2,3,0,0,0,0,0,0,0,0,0,0,0,0;
# 0 is for normal ethernet frames.
# 1 is for upto 4k size frames.
# 2 is for upto 8k size frames.
# 3 is for upto 16k size frames.
As of 16k(when "3" is specified), mtu is set to 8978,
Anybody who have T5220 could test this bug.
But anyway, there seems no such problem on sun T2000/ Solaris 10 u5.