01-13-2011 12:24 PM
Ok, now I am second questioning something...
to make this simple:
1 media server to tape Lt3 Pool A
add a second Media Server to share the drives/robots/ SSO and media license we purchased etc.
Can Media Server 2 also use Tape Pool A?
I ask becuase I see for media there is a "media Owner colum" and I cant recall the rules for this.
basically from the past in checking I was told no problem, create a shared storage pool and it does not matter, but when I look at this I am questioning it as to me it seems if Media Server 2 uses a tape it does it become "sole owner of it" and it would make sense to me to separate the pool.
Any thoughts?
Thanks
Scott
Solved! Go to Solution.
01-14-2011 06:24 AM
The default behaviour across all NBU versions is media ownership. The media server who first writes the tape owns it. Once all images expire, it becomes available and another media can write to it and assume ownership.
NBU 6.5 introduced media sharing that can be done in two ways: Media Server Groups - media servers in a particular group can all write to same media, or Unrestricted Sharing (enabled in Host Properties) where ALL media servers can share ALL tapes. Media Sharing has to be enabled by the backup Admin.
01-13-2011 02:50 PM
I have 4 media servers using the same volume pool.
Yes when a media server takes a tape and buts backups to it that media server is listed as the owner.
If a restore request comes in for data on that tape, that media server will be asked to do the restore ( you can set the fail-over for restores to allow any body to do them if the media server is unavail)
The only real issue here is if media server A has a tape and does backups, and media server B has tapes and does backups.....
and media 1 gets full media server A will take another tape, as it cannot send data to a tape this is currently being backed up to by media Server B.
Once a tape is owned by a media server no other media server will use it, unless it is forced to by a restore.
01-13-2011 04:51 PM
By default this is the normal behaviour for NetBackup. This can amount to a large wastage of tapes, especially if you are vaulting your tapes to offsite. By default, tapes will not be shared between media server owners and this can translate to a large number of tapes being used, even if you are not backing up much data.
I think it is from version 6.5 where you can set up Server Groups to use media sharing (under Media and Device Management>Devices>Server Group). Here you can create a server group and assign media servers to that group between which you want to share the same media. You will then be able to configure the policies to use the shared server group as the Media Owner (under the Attributes tab for the policy).
Hope this helps.
01-13-2011 06:11 PM
Hi again
I might have read you question slightly wrong so this is an attempt to redeem myself
As J.Hinchcliffe mentioned, media servers can use tapes from the same pool without issues. If you don't have media sharing enabled (my previous post) the tapes that are in the same pool will be owned by the media server that first writes data to it. By default this tape will not be loaded by another media server for both writes or restores (again, as J.Hinchcliffe mentioned in his post).
If you want to bypass this behaviour by allow different media servers to share tapes between them, you can enable the media sharing feature (as in my previous post).
Cheers
01-14-2011 05:38 AM
Hi Guys:
Your response is right on, as my thoughts were media server a would own the tape and media server b would now not use it.
Dion: I am looking into the Server Group item you mention to better understand this, interesting as I sent this question to Symantec and this is thier response:
"
01-14-2011 06:24 AM
The default behaviour across all NBU versions is media ownership. The media server who first writes the tape owns it. Once all images expire, it becomes available and another media can write to it and assume ownership.
NBU 6.5 introduced media sharing that can be done in two ways: Media Server Groups - media servers in a particular group can all write to same media, or Unrestricted Sharing (enabled in Host Properties) where ALL media servers can share ALL tapes. Media Sharing has to be enabled by the backup Admin.
01-14-2011 08:08 AM
Hi There:
Ok from what Mariannne is saying
sounds like I DONT need Server Groups but only to enable media shareing.
This lead me to look at the tap and here is what I found and sounds like that needs to be done, to simply allow BOTH Meida servers share the media if they need to.
I need to also explain, media Server A is on one network
Media Server B is on another network, this is allowing me help improve traffic flow for clients on both sides, but allow clients in either side, should they need a tape write to it which may not be the best ideal, but then it would depend on how I want to keep this clean at which point.
From the book, media shareing is actually off by default:
To allow all NetBackup media servers and NDMP hosts in your NetBackup environment to share media for writing, select this property. Do not configure server groups for media sharing.
■ To restrict media sharing to specific server groups, clear this property, then configure media server groups and backup policies to use media sharing.
■ To disable media sharing, clear this property and do not configure media
server groups. By default, media sharing is disabled
Scott
01-14-2011 08:39 AM
One more item if anyone is reading this or cares,
when you enable this, it will apply to media that has not been assigned yet, so
if you have media already assigned, it wont be shared until you clear it or make it a scratch again.
Thanks to all of you who got me in the right direction for this, as this question was burning in my head, and I guess I couldnt find the right words to look it up correctly what I was looking for.
01-14-2011 09:22 AM
If you're happy that the media sharing option is the way to go & has resolved/will resolve your issue, please come back & mark Mariannes post as the solution.
01-14-2011 10:04 AM
hmmm I thought I did mark them, as thanks to Dion and Marianne
they got me in the area I needed, I do apoligies let me check what I did or did not do.
Again thanks for the feed back as I knew what I needed but didnt know the right combination to look at and this is what I was looking for.
01-14-2011 10:58 AM
That could be my bad - sorry!