IP aliasing in Linux Red Hat 2.4.20-8

Hello All,

I have a Linux machine 2.4.20-8. I was in need of IP aliases in this
machine, about 2000 of them. After creating about 500 IP Aliases I
restarted the network services. I was able to ping to my machine
through the virtual IPs I had created. Then I in one shot created 2000
ifcfg files..
ifcfgeth0:1 ...ifcfgeth0:2000. I rebooted the machine. But on reboot,
the boot process has hung @ "Bring up interface eth0: "...The machine
has not come out of this state. What do I do ?
Was 2000 a high number for IP Aliasing.

Replies to the query is highly appreciated.

Thanks and Regards,

Prabhu.S

On 27 Jun 2006, in the Usenet newsgroup comp.os.linux.networking, in article
<(E-Mail Removed) .com>, Prabhu wrote:

>I have a Linux machine 2.4.20-8.

That's the original "out-of-box" kernel for Red Hat 9, which means the
system hasn't been maintained (Red Hat released eight kernel errata, and
there have been three more released by download.fedoralegacy.org since
Red Hat stopped support of that version a little over two years ago).

>I was in need of IP aliases in this machine, about 2000 of them.

One has to wonder, why?

>But on reboot, the boot process has hung @ "Bring up interface eth0:
>"...The machine has not come out of this state. What do I do ?

Bring the system up in single usermode. I'm assuming you are using GRUB.

1. If you have a GRUB password configured, type p and enter the password.
2. Select Red Hat Linux with the version of the kernel that you wish to
boot and type e for edit. You will be presented with a list of items in the
configuration file for the title you just selected.
3. Select the line that starts with kernel and type e to edit the line.
4. Go to the end of the line and type single as a separate word (press the
[Spacebar] and then type single). Press [Enter] to exit edit mode.
5. Back at the GRUB screen, type b to boot into single user mode.

If single does not work, try a 1 instead.

When the system boots, get rid of all of those alias files. After you fix
this problem, you should really consider getting the system up to date,
or even replacing it with a less antique distribution.

>Was 2000 a high number for IP Aliasing.

How is your kernel configured? In the IP-Alias mini-howto,

-rw-rw-r-- 1 gferg ldp 13575 Jan 26 2001 IP-Alias

the author mentions a limit set in /usr/include/linux/net_alias.h as
being set to 256 aliases, which are quite a high number anyway.

Old guy

Moe Trin wrote:
> On 27 Jun 2006, in the Usenet newsgroup comp.os.linux.networking, in article
> <(E-Mail Removed) .com>, Prabhu wrote:
>
> >I have a Linux machine 2.4.20-8.
>
> That's the original "out-of-box" kernel for Red Hat 9, which means the
> system hasn't been maintained (Red Hat released eight kernel errata, and
> there have been three more released by download.fedoralegacy.org since
> Red Hat stopped support of that version a little over two years ago).
>
> >I was in need of IP aliases in this machine, about 2000 of them.
>
> One has to wonder, why?
>
> >But on reboot, the boot process has hung @ "Bring up interface eth0:
> >"...The machine has not come out of this state. What do I do ?
>
> Bring the system up in single usermode. I'm assuming you are using GRUB.
>
> 1. If you have a GRUB password configured, type p and enter the password.
> 2. Select Red Hat Linux with the version of the kernel that you wish to
> boot and type e for edit. You will be presented with a list of items in the
> configuration file for the title you just selected.
> 3. Select the line that starts with kernel and type e to edit the line.
> 4. Go to the end of the line and type single as a separate word (press the
> [Spacebar] and then type single). Press [Enter] to exit edit mode.
> 5. Back at the GRUB screen, type b to boot into single user mode.
>
> If single does not work, try a 1 instead.
>
> When the system boots, get rid of all of those alias files. After you fix
> this problem, you should really consider getting the system up to date,
> or even replacing it with a less antique distribution.
>
> >Was 2000 a high number for IP Aliasing.
>
> How is your kernel configured? In the IP-Alias mini-howto,
>
> -rw-rw-r-- 1 gferg ldp 13575 Jan 26 2001 IP-Alias
>
> the author mentions a limit set in /usr/include/linux/net_alias.h as
> being set to 256 aliases, which are quite a high number anyway.
>
> Old guy

Hello Moe,

Thanks for your detailed writ-up..I had my left my machine as it was
...after about 4 hours it did eventually come up. And I was to ping
quite a number of aliases that I chose randomly.Guess all the aliases
are active.!

Yeah..2000 is bit high..needed to run a tool on the machine which would
emulate 2000 clients to connect to a server(To stress test the server)..