Subject: One More Time ... loopback
From: "Roderick A. Anderson" <raanders@acm.org>
Date: Tue, 05 Aug 2008 13:59:28 -0700

I tried using the /etc/vservers/guest/interfaces/lback to assign a 
specific IP to the loopback device.  It is not working.  When I run
"ip addr ls" in the guest I still see 127.0.0.1.

The address I'm trying to assign is 127.0.1.196.  This is based on the 
last octet of the external IP and the device it is assigned to.

I am running the latest kernel and utils from Daniel's CentOS (5) 
repository.

cat /proc/version shows:

Linux version 2.6.22.19-vs2.3.0.34.1 (mockbuild@x86.builders.hozac.com) 
(gcc version 4.1.2 20070626 (Red Hat 4.1.2-14)) #1 SMP Mon Mar 17 
05:32:04 EDT 2008

The error, during the guest startup is:

Bringing up loopback interface:  arping: socket: Operation not permitted

This is a guest running postfix configured for local relay only.  I.e. 
(in case I've got my terminology all in a knot) programs that do some 
reporting can send email but the system will (should) never receive email.

Is there anything else I need to do to get the "loopback" device working?


TIA,
Rod
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