High Availability Solution

[Matthew Seaman]

On Tue, Aug 24, 2004 at 03:41:41PM +0300, Joseph Begumisa wrote:
 
> Does anyone know of a high availability solution that works on freebsd?  I 
> have two freebsd servers and would like to have them operate in a way that 
> if one fails, the second kicks in.

How you do this depends very much on the nature of the services those
machines are providing.  If it's a stateless service -- like serving
out static content from a web server, then you can use a pretty
rudimentary web switch that just round-robins between the two -- see
the Apache docs on mod_rewrite and mod_proxy for some ideas.

If you're building a firewall, then the PF firewall code recently
imported from OpenBSD is something you should find interesting: one of
it's excellent features is the CARP 'Common Address Redundancy
Protocol' which has been ported:

    http://pf4freebsd.love2party.net/carp.html

but I'm not sure if it's going to be in the up-and-coming 5.3-RELEASE.

Beyond that, there are any number of tricks using net/freevrrp -- the
trick with these however is to ensure that any necessary data
containing the state of a session is distributed over all of the
servers, or else failover won't work quite so well.  Most databases
have replication features nowadays (MySQL has this available by
default in the standard install, for Postgresql, look at the
databases/slony1 port.)

Other sorts of service -- well, to get a more precise answer you'll
just have to describe what you want to do in a less vague way.

	Cheers,

	Matthew

-- 
Dr Matthew J Seaman MA, D.Phil.                       26 The Paddocks
                                                      Savill Way
PGP: http://www.infracaninophile.co.uk/pgpkey         Marlow
Tel: +44 1628 476614                                  Bucks., SL7 1TH UK
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 187 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-questions/attachments/20040824/4e39d428/attachment.bin