Ran into a strange issue with XEN on CentOS that I think is specific to CentOS, which is why I'm starting by posting to this list first, I'll post on the XEN list depending on responses. My sense is this issue has something to do with how CentOS handles network setup on first boot of the XEN kernel.
- Installed a brand new CentOS 5.3 server with minimal packages.
- Installed XEN, modified grub.conf to boot off of the XEN kernel and rebooted.
- After reboot, network connectivity was lost.
- Investigation concluded the issue was that the HWaddr address of the physical NIC matched the fabricated HWaddr that XEN uses for most of its adapters: FE:FF:FF:FF:FF:FF.
- Temporary resolution, I re-enabled the motherboard's NIC, rebooted, all seems to be working.
I would like to get the NIC in question working as it is a GigaBit NIC, but it still has the HWaddr: FE:FF:FF:FF:FF:FF which conflicts with XEN.
My understanding of the HWaddr is that the first portion is manufacturer assigned for uniqueness, I cannot image this NIC originally had this HWaddr, but I don't know what it originally was.
Does anyone know if this value is read from the NIC on each boot, or is it stored in a file after the first boot? Is there someway to undo this change so the NIC returns to its original value or atleast a non-conflicting value?
Has anyone else seen this behavior?
Thank you in advance,
Brett