2001-12-06 23:07:48

by Hein Roehrig

Subject: network interface names ethX and renaming interfaces

Hello *,

in Linux 2.2.20 I have a problem renaming the network interface dummy0
to eth0 and then starting a regular ethernet driver --- I would like
it to come up as eth1 but it comes up as eth0, messing up the dummy0
interface.

Reading the source, it appears that in init_ethernev(), ethernet
drivers claim device names according to the array ethdev_index and
shoot down any device name eth0 claimed by a non-ethernet driver.

Therefore it appears to me that SIOCSIFNAME should either disallow
renaming to ethX or it should adjust ethdev_index.

Thanks in advance for any comment/advice,
Hein

2001-12-10 07:30:53

by Neale Banks

Subject: Re: network interface names ethX and renaming interfaces

On Fri, 7 Dec 2001, Hein Roehrig wrote:

> in Linux 2.2.20 I have a problem renaming the network interface dummy0
> to eth0 and then starting a regular ethernet driver --- I would like
> it to come up as eth1 but it comes up as eth0, messing up the dummy0
> interface.
>
> Reading the source, it appears that in init_ethernev(), ethernet
> drivers claim device names according to the array ethdev_index and
> shoot down any device name eth0 claimed by a non-ethernet driver.

I presume you are refering to init_etherdev() in drivers/net/net_init.c ?

> Therefore it appears to me that SIOCSIFNAME should either disallow
> renaming to ethX or it should adjust ethdev_index.

I wonder why it doesn't either use dev_alloc_name() from
net/core/dev.c , or implement similar logic?

Regards,
Neale.