Red Hat Bugzilla – Bug 129096
dhcp cannot be enabled for pseudo-devices/ethernet aliases
Last modified: 2007-11-30 17:10:46 EST
Description of problem:
With system-config-network GUI , users can create an 'Ethernet alias'
pseudo-device such as eth0:0 and enable dhcp on it; dhclient is,
however, unable to operate with such a device.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Select Devices->New and create an ethernet device from an existing
2. A device such as 'eth0:0' is created.
3. You are prompted to configure the card with dhcp enabled by default
If you specified 'activate' (ONBOOT=yes), or do an ifup for
the device, then dhclient will write a message to the log:
'Bind socket to interface: No such device'
and exit abnormally,
and the ifconfig fails with
'SIOCSIFFLAGS: Cannot assign requested address'.
The pseudo-device is not brought 'UP', can never be brought up,
and is quite useless until BOOTPROTO=none for it.
The design of dhclient is based on obtaining a PF_PACKET socket
bound to its interface; a PF_PACKET socket cannot be bound to
The user should not be allowed to enable DHCP on a pseudo interface.
There are numerous dhcp bugs on this issue, eg. bug 127272,
bug 124022, to name a few.
It is very confusing for users and a source of major annoyance.
dhclient cannot easily be changed to allow dhcp configuration of
pseudo-interfaces - it should be used to configure the real interface,
then the user would be able to create as many pseudo-interfaces with
static IPs as they like .
*** Bug 114145 has been marked as a duplicate of this bug. ***