Best way to move to a new system

[Chrisl_2]

Hi all. We have an old L class system in production and we have purchased a new rp3410 to replace it. I am trying to figure out a strategy for cutting over to the new system, with consideration to getting users, printers, apps, cronjobs, kernel tweeks, etc, etc in place. I currently use a combination of make_tape_recovery and rsync scripts (to a linux box) for backup. Would someone put me on the right track as to how I should go about doing this? Maybe there is a whitepaper or something also.

TIA Chris

[Pete Randall · Accepted solution]

Chris,

My usual approach is to cold-install the new box, restore the contents of /home and your configurations (/etc/passwd, nsswitch.conf, printers and all the other miscellaneous stuff particular to your environment) onto it, test in parallel, then cut over.

You don't say what this system does nor how it's storage is set up so that might make a difference as well. SAN attached storage can be migrated over to the new box via vgexport/vgimport. Your application needs should also be taken into consideration.

That's a pretty high level view.


Pete

[Chrisl_2]

Thanks. As soon as I posted it, I realized I forgot the storage info. Both the old and new systems use internal disks (mirrored) only, no disksubsystems. The system mainly runs a specialized application that supports a university card and reader system.

[Rita C Workman]

Chris

Like Pete mentioned you'll have to set up everything O/S related...quick rcp of things once the new box is on the network will help.

But if your disk is strictly internal and there is no 'shared' disk environment, then you will need to be sure your apps are down and do a couple solid tape backups, cause looks like you'll be restoring via tape.

So your looking at a good bit of downtime to restore your data to new internal disks.
Might want to consider getting some kind of shared disk environment for future.

Rgrds,
Rita

[James R. Ferguson]

Hi Chris:

In lieu of copying your application (non-vg00) data to tape and then to the new server's disk, I'd consider using a recursive 'rcp' from your old server to empty filesytems on the new one. Depending on the number and size of files; your backup hardware and your LAN, you might find that a network transfer is quite fast.

As mentioned, of course, your source filesystems must not be in use during the transfer.

Regards!

...JRF...

[Chrisl_2]

Is there a way to utilize make_tape_recovery? I understand that there are hardware platform and OS version issues with this....is there a way to avoid them?

TIA

[Pete Randall]

Well, make_tape_recovery is really better suited to OS disaster recovery - to get your operating system back up so that you can utilize your regular restore facilities to recover your non-OS data. You can ask it to include other than vg00, but I'm not quite sure that's going to do you any more good than just tar'ing vg01.


Pete

[Christian Schulze]

Hi Chris,

I did something similar several times.
The first thing is to startup your new system with a new hostname. Then you copy all your applications from the old system to the new one via lan.

After that you run some test to make sure that all apps are running as desired. This Testphase may take up to several weeks, dependend on how many apps from differnet vendors and so on.

After fixing all problems (I am sure you will find some) then its time to swap ... (some time, where you can afford downtime for your apps)

stop all apps on both systems, copy data from old system to new system, when done, then change hostname on both systems that new system will get old-hostname and the old system will get the new-hostname.

This way you dont have to touch any apps out there, they will all use the new host.

Christian