Help! Instable network on 6.06 based SuperMicro server with e1000 Intel driver

[Floris Vlasveld]

> On 24 feb 2008, at 21:49, Aart Koelewijn wrote:
>
>> On Sun, 24 Feb 2008 21:22:23 +0100, Floris Vlasveld wrote:
>>
>>> On 24 feb 2008, at 16:52, Nick Webb wrote:
>>>
>>>> Floris Vlasveld wrote:
>>>>>
>>>>> And, the output of "ethtool eth0" and eth1:
>>>>>
>>>>> Settings for eth0:
>>>>> Supported ports: [ TP ]
>>>>> Supported link modes:   10baseT/Half 10baseT/Full
>>>>>                      100baseT/Half 100baseT/Full
>>>>>                      1000baseT/Full
>>>>> Supports auto-negotiation: Yes
>>>>> Advertised link modes:  10baseT/Half 10baseT/Full
>>>>>                      100baseT/Half 100baseT/Full
>>>>>                      1000baseT/Full
>>>>> Advertised auto-negotiation: Yes
>>>>> Speed: 100Mb/s
>>>>> Duplex: Full
>>>>> Port: Twisted Pair
>>>>> PHYAD: 0
>>>>> Transceiver: internal
>>>>> Auto-negotiation: on
>>>>> Supports Wake-on: umbg
>>>>> Wake-on: g
>>>>> Current message level: 0x00000007 (7) Link detected: yes
>>>>>
>>>>> Settings for eth1:
>>>>> Supported ports: [ TP ]
>>>>> Supported link modes:   10baseT/Half 10baseT/Full
>>>>>                      100baseT/Half 100baseT/Full
>>>>>                      1000baseT/Full
>>>>> Supports auto-negotiation: Yes
>>>>> Advertised link modes:  10baseT/Half 10baseT/Full
>>>>>                      100baseT/Half 100baseT/Full
>>>>>                      1000baseT/Full
>>>>> Advertised auto-negotiation: Yes
>>>>> Speed: 100Mb/s
>>>>> Duplex: Full
>>>>> Port: Twisted Pair
>>>>> PHYAD: 0
>>>>> Transceiver: internal
>>>>> Auto-negotiation: on
>>>>> Supports Wake-on: umbg
>>>>> Wake-on: g
>>>>> Current message level: 0x00000007 (7) Link detected: yes
>>>>
>>>> I have similar SuperMicro servers with no issues.  I'd look first  
>>>> at
>>>> the
>>>> switch this server is connect to and make sure the ports are set to
>>>> auto
>>>> negotiate just like your interfaces are.  If they are set to auto
>>>> negotiation, then I'd force them to 100/full and do the same to  
>>>> your
>>>> server's network cards.  I've seen speed/duplex mismatches cause
>>>> lots
>>>> of
>>>> odd problems before.
>>>>
>>>> Aside from that, I'd be looking for hardware issues.  See anything
>>>> odd
>>>> in the logs?
>>>>
>>>>
>>>> Nick
>>>
>>>
>>> Thanks for the tips Nick. I've first of all forced eth0 (the
>>> 'external'
>>> interface) to operate at 100/Full. However, that didn't stop the
>>> problem. I then changed the settings so that eth0 was allowed to
>>> negotiate, but only up to 10/Full. Unfortunately, this didn't solve
>>> the
>>> problem as well. At this time, I'm not able to force the 3com
>>> switch to
>>> operate at 100/full only. However, it should be able to handle both
>>> 100/full and 10/full perfectly.
>>>
>>> Output of ethtool eth0 at this time:
>>>
>>> Settings for eth0:
>>> 	Supported ports: [ TP ]
>>> 	Supported link modes:   10baseT/Half 10baseT/Full
>>> 	                        100baseT/Half 100baseT/Full
>>> 	                        1000baseT/Full
>>> 	Supports auto-negotiation: Yes
>>> 	Advertised link modes:  10baseT/Full
>>> 	Advertised auto-negotiation: Yes
>>> 	Speed: 10Mb/s
>>> 	Duplex: Full
>>> 	Port: Twisted Pair
>>> 	PHYAD: 1
>>> 	Transceiver: internal
>>> 	Auto-negotiation: on
>>> 	Supports Wake-on: umbg
>>> 	Wake-on: g
>>> 	Current message level: 0x00000007 (7) Link detected: yes
>>>
>>> Hardware issue is of course always possible. However, since both  
>>> eth0
>>> and eth1 display this problem, that seems quite unlikely.
>>>
>>> Do you or anybody else have any other suggestion?
>>>
>>> Floris.
>>
>> With such a problem I would always check route. It has happened to me
>> that there are 2 default routes or none at all. In both cases you  
>> will
>> have problems with your network.
>>
>> Aart
>
> Thanks for your reply Aart. How exactly would I check that? What do I
> look for?
>
> Output of "route" is as follows:
>
> Kernel IP routing table
> Destination     Gateway         Genmask         Flags Metric Ref
> Use Iface
> 80.69.93.0      *               255.255.255.128 U     0      0
> 0 eth0
> 10.0.0.0        *               255.255.255.0   U     0      0
> 0 eth1
> default         10.0.0.1        0.0.0.0         UG    0      0
> 0 eth1
> default         80.69.93.1      0.0.0.0         UG    0      0
> 0 eth0
>
>
Wow! You just solved my problem Aart. I indeed had two default routes,  
as you can see. Removing the gateway on the second NIC solved it.  
Thanks a lot!