Comment 4 for bug 1561096
Revision history for this message
| bugproxy (bugproxy) wrote Comment bridged from LTC Bugzilla | #4 |
© 2004
Canonical Ltd.
•
Terms of use
•
Data privacy
•
Contact Launchpad Support
•
Blog
•
Careers
•
System status
•
a60fb26
(Get the code!)
------- Comment From <email address hidden> 2016-04-05 10:26 EDT-------
(In reply to comment #16)
> > This creates a name-slip problem for these ibmveth devices depending on the timing of other devices (where another NIC will temporarily be assigned a name like eth0 before it is renamed by udev).
>
> Can you please explain this further? The kernel should always pick a new
> eth* name and avoid name clashes with existing eth* devices, and udev (since
> Ubuntu 15.04) will never assign a name like "eth*" which potentially
> collides with the kernel default names. At least that's the current
> assumption, if that is invalid and you actually see a device being *re*named
> to "eth*", this is what we need to fix.
At the time of the install, only one network device existed (the ibmveth device). This was assigned the name eth0, and this is what the installer recorded in the interfaces file. After the install, additional physical NICs were added to the system. Upon boot, one of the new NIC's driver loaded first and temporarily grabbed the eth0 name. When the ibmveth driver loaded, it grabbed eth1 (since eth0 was taken at the time). Eth0 was subsequently renamed (as you noticed in the logs), but the ibmveth device name had already slipped, and now there was no longer an eth0 device to go with the configuration in the interfaces file.
> I'm a bit confused why there are two different device drivers claiming the
> same device, though.
As noted, network device additions post-boot.
> After booting, what does "ip a" show, i. e. which ethernet devices do you
> actually have? It would also be helpful to attach the output of "udevadm
> info --export-db" to show me which information udev collected about the
> ethernet devices.
This information should be contained in the sosreport attached.
> Did you manually put "eth0" into /etc/network/
> by the installer? The latter would mean that the installer environment names
> devices differently than the installed OS (that'd be a major bug indeed).
Done by the installer due to the installation being done while there was only the ibmveth device.