Re: rman backup to tape
Date: Wed, 6 Jan 2010 22:51:13 +0530
yeah backup team doing testing to see if it improves backup timings..
On Wed, Jan 6, 2010 at 10:31 PM, Jared Still <jkstill_at_gmail.com> wrote:
> On Wed, Jan 6, 2010 at 5:32 AM, Nagaraj S <nagaraj.chk_at_gmail.com> wrote:
>> Good Morning All,
>> I have clarification on rman backup to tape. Suppose if backup team
>> increase the netbackup streams from 2 to 8, will it decrease the database
>> backup completion time window? And also how to make changes on rman script
>> to configure the new streams build by backup team and how rman can
>> communicate to backup each stream data’s on each tapes separately... Thank
> If there are 8 drives available, then it may decrease the time required for
> a backup.
> If the network from the server to the tape library doesn't have the
> bandwidth to
> accommodate that much data, then the backups may actually take longer than
> with 2 drives.
> This is because tapes must be kept streaming to be efficient.
> When tape drives run out of data to write, they stop and rewind.
> When more data needs to be written, the tape drive must then
> seek to where it left of writing.
> Here's an article on the topic:
> Increasing the number of drives in use will also make those drives
> unavailable for other backup jobs.
> Increasing the number of drives will also increase the number of tapes
> that must be vaulted (sent offsite)
> The real question is: Did the backup team do their homework when
> deciding to increase the number of drives from 2 to 8?
> Jared Still
> Certifiable Oracle DBA and Part Time Perl Evangelist
> Oracle Blog: http://jkstill.blogspot.com
> Home Page: http://jaredstill.com