All of lore.kernel.org
 help / color / mirror / Atom feed
From: Grant Taylor <gtaylor@riverviewtech.net>
To: lartc@vger.kernel.org
Subject: Re: [LARTC] Best setup for redundant routers.
Date: Fri, 07 Dec 2007 02:19:39 +0000	[thread overview]
Message-ID: <4758ADBB.6030905@riverviewtech.net> (raw)
In-Reply-To: <7C454E01C5FAE748BEFE65F4C6B7FD8BFD2128@s-marcell.hemc.coop>

On 12/6/2007 11:40 AM, Shane McKinley wrote:
> Wouldn't the redundant VRRP cause an IP address conflict?

No.  Let me try to explain using pseudo IP addresses.  For the sake of 
discussion we will use the RFC test network of 192.0.2.0/24.  (All IPs 
below will be just the last octet in said subnet.)

Real routers A and B (RA and RB respectively) and virtual routers A and 
B (VA and VB respectively) will make up the routers of the network.

Have RA be primary for VA's IP and backup for VB's IP.  Then have RB be 
backup for VA's IP and primary for VB's IP.  So you would have four IPs 
in use (RA, RB, VA, and VB).  You would only have clients use VA and / 
or VB as their default gateway(s).

So, if you have the following IPs used:

VA = .254
VB = .253
RA = .252
RB = .251

Real router A would have it's ""management IP of .252 and participate 
(as the primary) in the VRRP virtual router A IP / MAC address of .254 
and (as the secondary) in the VRRP virtual router B IP / MAC address of 
.253.

Real router B would have it's ""management IP of .251 and participate 
(as the secondary) in the VRRP virtual router A IP / MAC address of .254 
and (as the primary) in the VRRP virtual router B IP / MAC address of .253.

As you can see there are four IP addresses used, two are what clients 
would use as potential default gateways and two are for management of 
the real routers.

With the two different IPs that you can hand out to clients, you could 
do some load balancing by having some clients use one virtual router and 
others use the other virtual router.

Heck, if you wanted to you could even add a third real router (RC) to be 
a tertiary router for virtual routers.

> If not, that would be sweet. I would have redundancy for my redundancy.

Start thinking about how sweet things can be....



Grant. . . .
_______________________________________________
LARTC mailing list
LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc

  parent reply	other threads:[~2007-12-07  2:19 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-12-06 16:43 [LARTC] Best setup for redundant routers Shane McKinley
2007-12-06 17:15 ` Grant Taylor
2007-12-07  2:19 ` Grant Taylor [this message]
2007-12-07  2:30 ` Mohan Sundaram

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4758ADBB.6030905@riverviewtech.net \
    --to=gtaylor@riverviewtech.net \
    --cc=lartc@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.