[Fedora-xen] Routing doesn't work when I boot with the Xen kernel

[John Summerfield]

Jack Smith wrote:
> I have a choice of kernels to boot with in Grub,
> 2.6.21-2952.fc8xen
> 2.6.23.9-85.fc8
> 2.6.23.1-42.fc8
> 
> As far as I can see, I have networking set up the same on all three.
> (Besides, wouldn't they use the same configuration files at boot time?)  My
> problem is, when I boot with the xen kernel, I can't get out through my
> router.  I can ping everything on my eth0 or eth1 networks, just not go
> through my eth0 Linksys router.  The only difference I've been able to see
> is that something called "peth0" uses the same card as the NIC my router is
> on.  Is this getting in the way somehow?
> 
>  eth0 Link encap:Ethernet HWaddr 00:17:31:01:C8:A8
>

Check that the NICs are both connected to the same wire with the 
different kernels. if I read it correctly, they're both the same brand. 
Maybe the kernels detect them differently.

Unplug one, test with ethtool:
sudo ethtool eth0

Find and inspect the configuration files:
[summer at potoroo ~]$ locate ifcfg-eth
/etc/sysconfig/network-scripts/ifcfg-eth0
[summer at potoroo ~]$ cat /etc/sysconfig/network-scripts/ifcfg-eth0
# Intel Corporation 82566DM Gigabit Network Connection
DEVICE=eth0
BOOTPROTO=dhcp
HWADDR=00:18:71:84:A5:9E
ONBOOT=yes
[summer at potoroo ~]$

The HWADDR line ties the MAC address to the interface configuration, but 
I've never had the need to explore how it works, and I can imagine some 
different ways.



-- 

Cheers
John

-- spambait
1aaaaaaa at coco.merseine.nu  Z1aaaaaaa at coco.merseine.nu
-- Advice
http://webfoot.com/advice/email.top.php
http://www.catb.org/~esr/faqs/smart-questions.html
http://support.microsoft.com/kb/555375

You cannot reply off-list:-)