migration tips and tricks

[Danny Pogi]

hi guys,

i've read so much success stories regarding migration from a v-class server to superdome. however, i would like to have a documentation for my collection on how exactly the migration was performed, things like the tools needed, how the database was migrated, etc. would be very glad to get your insights. thanks

regards,
danny

[Michael Tully]

I don't see any difference between moving data from V to superdome or any other server.

Here's a rough guide to start:
Build your new system, here's a good link for general info: http://forums.itrc.hp.com/cm/QuestionAnswer/1,11866,0x4499e7e60861d511abcd0090277a778c,00.htm
If your moving applications as well, if your using the same OS version, i.e. 11i, then again I see no huge obstacles.
It all depends on the disk being used, (migrated or new) kernel parameters required for the database/application.

If you plan on utilising the same disk, then it is in reality quite simple. If not you'll have to use a either backup and restore mechanism, or an export to disk.
If you are utilising the same disk array, then you can do this:

vgexport from the V class for each volume group (must be done in preview mode -p)
vgexport -m myvg.mapfile -p -v /dev/myvg (save the map files)

vgimport on the new system, for each volume group
vgimport -v -m myvg.mapfile -p /dev/myvg (look for errors)
if no errors
vgimport -v -m myvg.mapfile /dev/myvg
Create new filesystems for each logical volume that needs to be mounted.
If you like I can post a couple of examples.
Hopefully there is some things to get you started.

[Danny Pogi]

yes mike, please do post some examples. and it would be best if you can have your examples having oracle as the database.

other concern is downtime, approximately, how much downtime would be required?

thanks.

[Michael Tully]

The downtime will depend entirely on the type of migration.

Here's what I would do:

Build your new server and install the oracle software (if possible)
When you ready
Shutdown the database on the old server
vgexport your vol groups (preview mode)
import your vol groups onto the new server and activate them
create the filesystems and mount them
disconnect old server
start the database
Downtime could vary depending on the complexity of your hardware the number and size of the databases and the window of opportunity. ALways make sure that you have sufficient time. Don't over commit yourself.

example of creating filesystems as attached.