I'm sorting out the disaster recovery plan for a critical server. It's a Dell PowerEdge 2850 running Openserver 5.0.6a.

We have a disaster recovery agreement with HP and they have just confirmed that in the event of a total disaster such as the server being totally wiped out, they would NOT bring an identical server for me to recover onto, but a "HP equivalent".

I'd rather recover with root/boot and back-up tapes as it's so much quicker than reinstalling etc, but I'm unsure what is involved to do this when the hardware is different.

I wondered if it would be possible to configure BTLD drivers for the RAID controller, tape controller and NIC at boot time, but I can't find much information on this. It looks like commercial products like BackupEdge can do this though.

Has anyone done this or have any advice for doing it?

The easiest solution is the replacement hardware having the same disk controller (driver) as the current system.
Next easiest is to build a target kernel for the proposed disk controller, and having it on the current system.
BackupEdge is a really really good solution.
Make sure that the tape drive and its controller will fit the new system, or that a replacement drive will read your tape.
Make sure that any add in cards that you have will work with the replacement hardware, or that you can find a suitable alternative.
Try to arrange your data so that the root file system contains minimal data.
eg. Move home directories to /u or /home.
Move mail boxes from /usr/spool/mail to /u/spool/mail (edit /usr/mmdf/mmdftailor).
Make a copy of /usr/spool/lp/admins/lp/interfaces, /etc/hosts, /etc/resolv.conf, /etc/rc2.d, and anything else you know about.
Use the ap command to make a copy of all user accounts and passwords.
This way, if you have to rebuild from scratch you will have the most amount of configuration and data on file systems that are easy to restore.

Thanks for your reply jgt.I've convinced myself to invest in BackEdge. It only costs about £350, so it's a no-brainer in my opinion.I'll keep your other suggestions in mind too. I'll test everything to ensure it all works first.Many thanks again.