How are device names assigned to eth devices?

I have an Agere Ethernet card with the et131x driver, which works.
However I am confused as to the device naming. I had it listed as
alias eth0 eth131x
in /etc/modprobe.conf
( with also an alias eth1 ipw3945 for the wireless). The eth131x would be
loaded first as shown in dmesg. and then the ipw3945 which was assigned the
device number eth1. But eth0 did NOT correspond to the eth131x device.
I later replaced that line with
alias eth2 eth131x
with an equivalent /etc/sysconfig/network-scripts/ifcfg-eth2 file
and now loh and behold, everything worked and the ethernet et131x came up at eth2
on bootup. Why in the world did eth0 not work? How are device numbers
assigned? and why is there no eth0 anywhere?

What routine is it that determines the numbering ( and naming) of the
devices-- ie assigns eth2 say to this device?

Thanks.

On Mon, 17 Sep 2007 03:40:30 +0000, Bill Unruh wrote:

> I have an Agere Ethernet card with the et131x driver, which works.
> However I am confused as to the device naming. I had it listed as
> alias eth0 eth131x
> in /etc/modprobe.conf
> ( with also an alias eth1 ipw3945 for the wireless). The eth131x would be
> loaded first as shown in dmesg. and then the ipw3945 which was assigned the
> device number eth1. But eth0 did NOT correspond to the eth131x device.
> I later replaced that line with
> alias eth2 eth131x
> with an equivalent /etc/sysconfig/network-scripts/ifcfg-eth2 file
> and now loh and behold, everything worked and the ethernet et131x came up at eth2
> on bootup. Why in the world did eth0 not work? How are device numbers
> assigned? and why is there no eth0 anywhere?
>
> What routine is it that determines the numbering ( and naming) of the
> devices-- ie assigns eth2 say to this device?
>
> Thanks.
see /etc/udev/rules.d/<number>-persistent-net.rules. This file is where
the rules of naming the interfaces are parsed.

nunya <business@127.0.0.1> writes:

>On Mon, 17 Sep 2007 03:40:30 +0000, Bill Unruh wrote:

>> I have an Agere Ethernet card with the et131x driver, which works.
>> However I am confused as to the device naming. I had it listed as
>> alias eth0 eth131x
>> in /etc/modprobe.conf
>> ( with also an alias eth1 ipw3945 for the wireless). The eth131x would be
>> loaded first as shown in dmesg. and then the ipw3945 which was assigned the
>> device number eth1. But eth0 did NOT correspond to the eth131x device.
>> I later replaced that line with
>> alias eth2 eth131x
>> with an equivalent /etc/sysconfig/network-scripts/ifcfg-eth2 file
>> and now loh and behold, everything worked and the ethernet et131x came up at eth2
>> on bootup. Why in the world did eth0 not work? How are device numbers
>> assigned? and why is there no eth0 anywhere?
>>
>> What routine is it that determines the numbering ( and naming) of the
>> devices-- ie assigns eth2 say to this device?
>>
>> Thanks.
>see /etc/udev/rules.d/<number>-persistent-net.rules. This file is where
>the rules of naming the interfaces are parsed.

I am confused. udev does not sound like something that would be handling
device names. And why would it be refusing to assign eth0 to the device but
be happy with eth2, esp since eth0 does not exist on the machine.
And what does udev use to assign those names? Ie there must be some program
that actually does the assigning.

On Mon, 17 Sep 2007 20:26:46 GMT, Unruh wrote:
>
> I am confused. udev does not sound like something that would be handling
> device names. And why would it be refusing to assign eth0 to the device but
> be happy with eth2, esp since eth0 does not exist on the machine.
> And what does udev use to assign those names? Ie there must be some program
> that actually does the assigning.

May depend on which linux you are running.

To get my eth0 straightened out I did a
rm -f /etc/iftab
rm -f /etc/udev/rules.d/61-net_config.rules
and setup values in /etc/sysconfig/network-scripts/ifcfg-eth0.
Then again I run Mandriva Linux.

On Mon, 17 Sep 2007 22:01:57 +0000, Bit Twister wrote:

> On Mon, 17 Sep 2007 20:26:46 GMT, Unruh wrote:
>>
>> I am confused. udev does not sound like something that would be handling
>> device names. And why would it be refusing to assign eth0 to the device but
>> be happy with eth2, esp since eth0 does not exist on the machine.
>> And what does udev use to assign those names? Ie there must be some program
>> that actually does the assigning.
>
> May depend on which linux you are running.
>
> To get my eth0 straightened out I did a
> rm -f /etc/iftab
> rm -f /etc/udev/rules.d/61-net_config.rules
> and setup values in /etc/sysconfig/network-scripts/ifcfg-eth0.
> Then again I run Mandriva Linux.
Bit Twister: What version of Mandriva are you running, and what version of
udev are you running? I'm running Gentoo 2.6.22-r5, x86-64, AMD64x2, 2GB
DDR2, Broadcom 4311, Dual layer Dual format DVDRW, Nvidia Geforce GO 6100,
FluxBox desktop (with some kde and some gnome programs), multiple servers
(internal LAN only) ...... a really sweet thing for a dev unit.
Unruh: What are you running?

On Mon, 17 Sep 2007 20:41:44 -0700, nunya wrote:
> On Mon, 17 Sep 2007 22:01:57 +0000, Bit Twister wrote:
>>
>> May depend on which linux you are running.
>>
>> To get my eth0 straightened out I did a
>> rm -f /etc/iftab
>> rm -f /etc/udev/rules.d/61-net_config.rules
>> and setup values in /etc/sysconfig/network-scripts/ifcfg-eth0.
>> Then again I run Mandriva Linux.
> Bit Twister: What version of Mandriva are you running,

$ cat /etc/release
Mandriva Linux release 2007.1 (Official) for i586
I have decided not to run 64 bit until the basic surfing plugins are
created for 64 bit machines.

> and what version of udev are you running?

Currently installed version: 106-3mdv2007.1

Bit Twister <(E-Mail Removed)> writes:

>On Mon, 17 Sep 2007 20:26:46 GMT, Unruh wrote:
>>
>> I am confused. udev does not sound like something that would be handling
>> device names. And why would it be refusing to assign eth0 to the device but
>> be happy with eth2, esp since eth0 does not exist on the machine.
>> And what does udev use to assign those names? Ie there must be some program
>> that actually does the assigning.

>May depend on which linux you are running.

>To get my eth0 straightened out I did a
>rm -f /etc/iftab
>rm -f /etc/udev/rules.d/61-net_config.rules
>and setup values in /etc/sysconfig/network-scripts/ifcfg-eth0.
>Then again I run Mandriva Linux.
So do I.
Never knew about iftab.
What progam uses it?
I had ifcfg-eth0 set up exactly the same as on the working ifcfg-eth2.
(except different eth devices of course).

nunya <business@127.0.0.1> writes:

>On Mon, 17 Sep 2007 22:01:57 +0000, Bit Twister wrote:

>> On Mon, 17 Sep 2007 20:26:46 GMT, Unruh wrote:
>>>
>>> I am confused. udev does not sound like something that would be handling
>>> device names. And why would it be refusing to assign eth0 to the device but
>>> be happy with eth2, esp since eth0 does not exist on the machine.
>>> And what does udev use to assign those names? Ie there must be some program
>>> that actually does the assigning.
>>
>> May depend on which linux you are running.
>>
>> To get my eth0 straightened out I did a
>> rm -f /etc/iftab
>> rm -f /etc/udev/rules.d/61-net_config.rules
>> and setup values in /etc/sysconfig/network-scripts/ifcfg-eth0.
>> Then again I run Mandriva Linux.
>Bit Twister: What version of Mandriva are you running, and what version of
>udev are you running? I'm running Gentoo 2.6.22-r5, x86-64, AMD64x2, 2GB
>DDR2, Broadcom 4311, Dual layer Dual format DVDRW, Nvidia Geforce GO 6100,
>FluxBox desktop (with some kde and some gnome programs), multiple servers
>(internal LAN only) ...... a really sweet thing for a dev unit.
>Unruh: What are you running?

Mandriva 2007.1

On Tue, 18 Sep 2007 16:26:31 GMT, Unruh wrote:

> So do I.

Guessed since I've seen you in the Mandriva group.

> What progam uses it?

Have not bothered to run it down. I did a Micro$not nic driver update
on a second tuesday. Booted linux and on board nic would not work.

Normaly a delete/add Network device fixed those except these lastest
releases of Mandriva Control Center.

Popped in a LinkSys nic, and saw the same kinds of eth0/1/2 problems.
Deleted the files and eth0 came up on the LinkSys. Never went back to
run down the problem.

Unruh <unruh-(E-Mail Removed)> writes:
> Never knew about iftab.
> What progam uses it?

It's used by ifrename to assign new names to network devices based on
some really flexible rules. After watching this conversation, it
sounds like it may be completely redundant on system with udev...