How can I prevent udevd from renaming eth0 to em1

[Bill Davidsen]

Michael H. Warfield wrote:
> On Sun, 2012-10-21 at 15:24 +1030, Tim wrote:
>> On Sat, 2012-10-20 at 22:41 -0400, Michael H. Warfield wrote:
>>> Following his instructions, I ended up with this:
>>>
>>> SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*",
>>> ATTR{address}=="00:19:b9:13:a8:fc", NAME="eth0"
>
>> Finding it hard to remember the plot, but is that rule set for matching
>> something the computer was doing?  (Rather than telling it to name it
>> eth0, it's asking if it's called eth0.)  Because, if your network isn't
>> called eth0, though you want it to be, then trying to match against an
>> eth0 that isn't being used, isn't going to match.
>
>> Isn't the behaviour, find this (rule set), then call it (something of
>> your own choosing, named somewhere else in the script/program/config)?
>
>> In which case, remove the name and eth0 clause.
>
> No, this worked for me.  If I included the KERNEL= and the other ATTR=
> clauses, it failed but I'm not sure which clause caused it to fail.  JD
> is saying it's still failing for him.
>
> Now that being said, there's still some notable differences.  Most of my
> machines (some F16 and some F17, some i686 and some x86_64) came up with
> p2p1 for interface names and his is coming up em1.  Obviously something
> is different.  Also, he's reporting a udevd change of the interface name
> in dmesg, which I'm not seeing even on the machines where it's still
> changing eth0 to p2p1.  So there's something significantly different in
> his set-up and maybe even versions that's making this difference.  I
> have one machine I have access to that is not mine that is showing em1
> as the interface name and it's an F16 i686 system (older Dell tower).
> It shows BOTH that name and that renaming.  If I tinker with it and
> break the networking, then I have to drive to that location to fix it.
>
> I did just discover that I have a Dell PowerEdge 2850 on hand that shows
> em1 and em2 as well as p3p1 and p3p2 (em1 is the main network
> interface).  That beast has F17 on it and udevd is reporting the
> interface changes like JD is seeing:
>
As I recall, the emN names are for internal NICs (on the system board) and the 
p{stuff} ones are for plugin NIC cards. I think it does something totally 
different and even less obvious for (a) a USB Wifi dongle, or (b) a USB to J45 
adapter.

> [mhw at toolroom ~]$ dmesg | grep udevd
> [    1.717298] udevd[152]: starting version 182
> [    3.314207] udevd[264]: renamed network interface eth1 to em2
> [    3.350217] udevd[264]: renamed network interface eth1 to p3p1
> [    3.642203] udevd[264]: renamed network interface eth1 to p3p2
> [    3.647220] udevd[266]: renamed network interface eth0 to em1
> [   14.564305] udevd[418]: starting version 182
>
> I can play with the other three interfaces and see what I can accomplish
> without risking the whole bloody server and a field trip.  This stuff
> has to be coming from somewhere.  I'll report back.
>
>> --
>> [tim at localhost ~]$ uname -rsvp
>> Linux 3.6.2-4.fc17.x86_64 #1 SMP Wed Oct 17 02:43:21 UTC 2012 x86_64
>>
>> All mail to my mailbox is automatically deleted, there is no point
>> trying to privately email me, I will only read messages posted to the
>> public lists.
>
> Regards,
> Mike
>
>
>


-- 
Bill Davidsen <davidsen at tmr.com>
   "We have more to fear from the bungling of the incompetent than from
the machinations of the wicked."  - from Slashdot