Networker

[Networker] Confusion over recycled save sets and tapes - need help

2011-06-29 17:39:58
Subject: [Networker] Confusion over recycled save sets and tapes - need help
From: George Sinclair <George.Sinclair AT NOAA DOT GOV>
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Date: Wed, 29 Jun 2011 17:38:15 -0400
I'm confused over the possible advantages/disadvantages of marking a tape manual recycle versus notrecyclable ('nsrmm -o notrecyclable volume'). There's just too many permutations to test all this myself, so I have several questions below that will help me to better understand this.

First, from what I do understand, when a save set reaches its retention period, the sumflags, ssflags, and clflags value will change to include an 'E' to indicate that the save set is eligible to be recycled (e.g. cE vrEF E instead of, say, cr vrF). Once all the save sets on the tape have expired then the tape is indicated as recyclable. If said tape is loaded into the tape library, and it's not physically write protected, then NW could overwrite the volume if it needed a tape, and there were no other available volumes. Even setting the tape to read-only (software option) will not prevent this behavior. This is defacto with NetWorker. That right?

HOWEVER, if the tape is set to manual recycle then NW will never recycle it. I assume that this does not change any of the mminfo attributes (e.g. ssretent, clretent, etc.) of the save sets but instead sets some flag (mminfo: manual) in the media database to indicate that the given tape cannot be recycled, correct?

BUT, if you set a tape to manual recycle, and at least one save set has not reached its retention period then that save set will still expire at some point. In other words, the 'manual' option does not prevent save sets from expiring, so if someone later changed the tape to 'notmanual', and all the save sets had already expired, and it was loaded into the library, then NW could overwrite it, yes?


Here are some questions:

1. What if you instead marked one save set on the tape as notrecyclable. If even just one save set is set like this then the tape cannot be made recyclable, right? Wouldn't this accomplish the same thing as the manual option?

Note: Here I'm assuming that the save set has not expired. If it has then I guess you need to first use nsrmm -e to change its clone retention time, and then you can make it notrecyclable which would then reset the ssretent to the same.

2. What if you set the clone retention time of one of the save sets to 'forever' or some date far in the future. Would this likewise result in basically the same result?

3. What's the better option? To make one save set notrecyclable or instead just assign it a clone retention time of 'forever'?

4. It seems like the safest way to prevent a volume from being overwritten would be to: a. change at least one save set to have a clone retention time of 'forever' or set that save set to notrecylable
b. change the tape to manual
c. write protect the tape
d. lock it away with a big ugly warning.
That sound right, in a paranoid way?

4. Can a tape marked as either manual recycle or notrecyclable be removed from the volumes listing?

5. Can a tape be made both nonrecyclable and manual?

6. Can a save set that is made notrecyclable be deleted from the media database (nsrmm -d)?

7. Once a volume is made manual recycle will NW also make it read-only(R)? Does that happen automatically?

Thanks.

George

--
George Sinclair
Voice: (301) 713-3284 x210
- The preceding message is personal and does not reflect any official or unofficial position of the United States Department of Commerce -
- Any opinions expressed in this message are NOT those of the US Govt. -

To sign off this list, send email to listserv AT listserv.temple DOT edu and type 
"signoff networker" in the body of the email. Please write to networker-request 
AT listserv.temple DOT edu if you have any problems with this list. You can access the 
archives at http://listserv.temple.edu/archives/networker.html or
via RSS at http://listserv.temple.edu/cgi-bin/wa?RSS&L=NETWORKER

<Prev in Thread] Current Thread [Next in Thread>