Re: IP_Alias and SysVInit

ATPlack (ATPlack@scj.com)
Mon, 30 Sep 1996 16:31:30 -0500


IMO, A matter of symmantics.

As I understand it, the "interface" does exist. It is just a pointer to the
master interface, in this case eth0.

Or are you saying (by the same measure) that the eth0 device does not exist
until it is defined in "ifup ifup-eth0"? When I check on my system (S10*
removed from rc3.d), I find that eth0 exists with a ip address of 0.0.0.0,
etc. Why shouldn't the ifconfig utility also show the same for eth0:0?

Even if this is true, and nothing about it changes, that still does not help
with bringing up aliases before other inet services.

Sure I could hack a S15alias script to force load this beast, or make a
ifup-alias script that is called by a hack to S10network but I thought that
I would ask if this is how this is SUPPOSED to work before doing it.

Thanks anyway. I appreciate the definition and discussion.

----------
From: davids@wiznet.net
To: ATPLACK@scj.com
Subject: Re: IP_Alias and SysVInit
Date: Monday, September 30, 1996 3:08PM

An aliased interface doesn't exist until it's given an IP.

DS

-----------------------------------------------------------------------
"Under Communism, state control of the economy eliminates organized
crime, and none of your cities suffer corruption or waste."
-- Civilization II instruction manual
-----------------------------------------------------------------------

On Mon, 30 Sep 1996, Anthony Plack wrote:

> Okay I am trying to setup an alias for my eth0 interface. I am using
> SysVInit on a Rembrandt Installation (Same thing on Slackware install so
> it is not this version).
>
> I have the rc3.d/S10network file runing the ifup in the
> /etc/sysconfig/network-scripts directory.
>
> Inside this directory I have the ifcfg-eth0 file and I also have create
> a ifcfg-eth0:0 file with the correct settings.
>
> This all seems to "run" correctly. from the init script except that the
> alias is being "Delayed".
>
> I traced the problem to the following line:
> /sbin/ifconfig ${DEVICE} 2>&1 | grep -s "unknown interface" > /dev/null
>
> if I run this line, step by step, I find out that the "/sbin/ifconfig
> eth0:0 2>&1" or "/sbin/ifconfig eth0:0" comes back with the following
> error:
> eth0:0::unknown interface
>
> The following line DOES work:
> /sbin/ifconfig eth0:0 192.168.1.1
>
> I am running ifconfig version 1.20 (Rembrandt) or ifconfig version 1.22
> (Slackware)
>
> Questions
> 1. Is this the correct place to put IP aliases for boot time loading?
> 2. Why does ifconfig not see that alias interface like this? Is there a
> patch for this?
> 3. Is the problem in the init scripts or in ifconfig?
> 4. What does "2>&1" do? I cannot find it anywhere.
>
> TIA
>
>