Re: back - up strategy

Anno Domini 21-4-2005 18:59, vidyesh sprak aldus:

>my consultant has designed a ha and back-up / dr strategy for me. i
>have a 50 gb oracle 8i db running on a single windows 2k advanced
>server.
>
>he is recommending that
>
>1. set - up a microsoft windows server cluster in active - active mode
>with another server and then run an oracle parallel failsafe on both
>these. this should take care of the ha problem.
>
>2. move the database to archive log mode. currently it is not so.
>
>3. take a nightly hot back - up to a server within the same data
>centre.
>
>4. multiplex the archivelogs and the control files to 3 diferent
>servers so we can have 3 copies of these on different servers.
>
>5. take a weekly cold back - up to a server within the same data
>centre. this is different than the one on which the nightly hot
>back-ups are kept.
>
>6. use oracle dataguard to take a back-up and ship the archive logs to
>a server within the same data centre. this server is different from the
>ones on which the hot and cold back-ups are kept.
>
>7. use oracle dataguard to take a back-up and ship the archive logs
>every 15 minutes to a server in a data centre about 1000 km away . this
>can be done over the internet thru a vpn.
>
>8. do an export / import of the whole database to another server in the
>data centre.
>
>i have some questions on his recommendations.
>
>- do i need to be doing all these things or is it an overkill? i do
>have the necessary servers and the consultant tells me that i dont need
>to pay oracle anything extra for all this.
>my data is all financial data and it is very critical as in if i lose
>it it will cause me a big financial loss.
>
>- can i avoid the setting up of a windows cluster and still acheive the
>ha part?
>
>- will all this impact the performance which my users are getting ?
>
>hey i know that was a long question but then so are my consultants
>recommendations.
>
>tia
>
>vidyesh
>
>
>

What are your uptime demands? Can you afford downtime? What is your backup retention time?

What is your worst case scenario? If you anticipate just loss of the building, then keeping the backups 1000km away perhaps is not necassery. If you anticipate a nuclear attack on your city, then it is possibly neither: the location 1000km away could be the next target and you might not expect electricity working for a long time. So keep things realistic. Depends on political stability (war and civil unrest), geological activity (earthquakes), forest (fire) and water (flooding).

There are several possabilities. Depends how much you are willing to pay.

• Upgrade to at least 9iR2. 8i is not supported anymore.
• multiplex archivelogs, control files and redologs. Keep on different disk array´s.
• make server hardware redundant (server clustering, raid 1+0, NIC).
• use RMAN for backups. No complicated scripts or database downtime. Include archivelogs, server parameter file and control file in backup plan. Plan to keep backups off site either on tape or on disk in a data centre on another location.
• get a backup solution (veritas, legato, galaxy) for Oracle and a tape library. Keep tapes off site (50G is still small enough for backup to tape)
• have a standby database ready on an other location on another server, copy archivelogs to this location and recover this stand-by database every hour. In case of disaster, you lost only the latest transactions and you are up and running in minutes.
• export/import is not a backup solution, You export if you plan to import later.
• plan for the loss of the DBA and system administrator who has remembered every procedure in his head and password and who wrote nothing on paper.