Since putting everything on the filer would be ideal it's not a reality as you have stated just in case there is a problem. Im consolidating 6 unix servers running Oracle dbase to 840 filer. I was thinking it would be nice to run the ORACLE_HOME dirs and logs from 2 unix servers rather than 6. Wonder if anyone has thought about consolidating that way or even if it a good idea...
-----Original Message----- From: Yarmas, Tom [mailto:Tom.Yarmas@netapp.com] Sent: Friday, March 09, 2001 1:14 PM To: 'Jennifer Armenta'; 'George Kahler'; toasters@mathworks.com Subject: RE: Multiple Oracle DBs on a filer
Is there a "best" method for where everything should be for multi dbases?
"Best" method, hmmm. I guess the easy answer is everything on the Filer, and if you need to save some space, have multiple instances share the ORACLE_HOME.
But in reality, there are enough variables that it depends on what you are trying to acomplish and how much local storage your database machine has. Typically, I find ORACLE_HOME on the database machine storage, and all of the datafiles, redo logs, etc on the Filer. Often the boot drives are large and mirrored, so there is plenty of space. Plenty being relative ;) Of course this tends to preclude failover in the case of a failed database machine unless a backup machine has an ORACLE_HOME installed on it. And if you duplicate the ORACLE_HOME onto multiple machines for failover, then there is a risk that some change was not propogated to all machines.
Of course, having multiple database instances within a single Filer volume has implications on SnapShots and SnapRestore/SnapMirror since these technologies work at the volume level. If you needed to do a SnapRestore for one instance, any others in the same volume would be affected. Similarly, when you take a SnapShot, the SnapShot would be for the entire volume, so it may be worthwhile to have multiple instances down (for a cold backup) or in hot backup mode for a hot backup. You generally do not want to have a seperate volume for each database instance unless they are large databases simply because each volume must have at least one parity disk, and you don't want volumes made up of a small number of drives if you can help it for performance.
The only things that need to be on local storage are the alert logs and the trace files directory. That is so that if a connection to the Filer is lost, Oracle can write it's alert info for troubleshooting. If you can't talk to your Filer, you want to be able to see info in the alert log to take action. And if you can't talk to your local disks, you know immediatly.
-tom