[Herefordshire] High Availability Linux

[Chris Bond]

Hi,

Just wondering if anybody here has any experience with High Availability
Linux?  I've just received three new servers to migrate my current exim
setup too, I want to do it using high availability so there's no downtime
though.

So far I've got the following:
- Redhat 3.0 Enterprise
- Redhat do there own clustering software however, im not sure if its what I
want
- /var/dspam and /home/mail need to be fully sych' incase of fallover, I
could either do this using external scsi enclosure or using something like
drbd.org
- Mysql 4 - full replication to secondary box
- Full service fallover, for bind, apache, exim, pop3, imap - the linux HA
project with a heartbeat should be able todo this.
- Want to advertise at least 2 hosts minimum in DNS so there's always a
route for mail

- Im currently using gradwell.net service for backup mail, however, the
third box I would like to put that at our office not the datacenter,
therefore being able to run secondary dns, backup mx, full replication
(prolly rsych) of data from main boxes as certain periods.

Any pointers as its quite a complex setup im trying to archive!  Should be
fun setting it up though.  Im in no rush to replace the current mail servers
as there currently coping very well, this is purely being put in for furture
expansion and resilent.

Kind Regards,
Chris Bond