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Introducing new media to tape rotation 1

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fvcu

MIS
Apr 12, 2000
24
CA
We just bought a Storagetek L20 tape library with Veritas BackupExec 8.6.
All of our previous DLTIV tapes are not compatible with the DLT1 drive so they must be degaussed in order to re-use them with the tape library or we must purchase all new tapes. Either way, it will be new media introduced to the backup routine.
[red]My problem is:[/red]
When I introduce new tapes with the barcodes for the appropriate media sets, I place the new media directly into the media set. I have set Veritas to take re-cylable media from the media set but it doesn't. It goes to the scratch media and just selects the first available tape, regardless of the label. As a result, it takes media labeled for another media set and I must manually change DLT labels and edit the backup log files.
Because I have around 125 DLTIV tapes to bring into the cycle, this automation solution is for the birds.
Have I done something wrong in my procedure?
Mike
 
Hello:

What do you have your Media Overwrite protection set to??? There are 2 settings for this option. -Overwrite scratch media before overwriting recyclable media or -Overwrite recyclable media contained in the target media set before overwriting scratch media. You may need to check this setting.
 
When you place media directly into a media set it automatically gets issued the overwrite/append protection as if the tape had just been written to. Even if you did nothing other than manually "move" it from "imported media" to "scratch media" after the system registered it.

The cleanest way to re-use imported tapes is to perform a quick-erase on each one. The system will automatically send the tape to the scratch pool. Once there, let the system move each tape, as it's used, into the appropriate media set.

If you want to control which tape is used from the scratch pool for a given backup, just move all of the unwanted media to a temporary media set so that there is only one tape left in the scratch pool. Once the backup job has picked it up, you can then move the next tape you want to be used into the scratch pool for the next job.

It seems like a convoluted mess, but it only needs done once. When all of the tapes are finally cycled out of the temporary media set you should be set with a stable rotation.

I hope this helps.
 
Torri,
That was the first thing I checked and I did have the wrong setting. Even after changing it to "Overwrite re-cyclable media" before scratch media, same problem.

Scanner,
What you say makes sense, however, I have multiple jobs scheduled to run overnight and I can't be there to move media around.
Here's another quirk - last night's jobs should have overwritten the media that had passed the overwrite protection period of 4 weeks. It appears that the media was moved to scratch media because it took media from the wrong media set to perform the differential backup. I can't hand this over to the operations people until I get all of the media introduced and the process working smoothly.
Mike
 
In that case, I wouldn't bother labelling the media until after the job(s) run. Something like this:

1. Quick-erase all of the imported media and just let it stay there in the scratch pool with the default media label assigned by BE (ie. 4MM000001).

2. Let the overnight backup jobs write to whatever media each job picks up.

3. Check the job logs in the morning and find the appropriate BE-assigned media name used on each job.

4. Rename/relabel each of the tapes used appropriately after the jobs have finished for the night.

That way each tape will be sent to the media set and issued the approprate retention scheme for your tape rotation and you won't have to worry about babysitting the tapes to make sure each job uses the media labelled for it. You will be letting the job determine which tape to label instead.
 
As for the second part of your message, I'm a little confused. Could you elaborate?
 
Last night's job should have written to media in the respective media set that had passed its overwrite period. The media became overwriteable. But BE took media that was labeled and in another media set. Perhaps I'll look into segmenting the library.
 
When you add a new tape (used or not), how do you inventory it (get the system to recognize it)? Do you inventory it via the tape library or do you use BE? If you use the tape library's inventory feature then BE may not be recognizing the tape exists. You should be using BE to import the tape and inventory the library.

-Bill
 
I seem to have the same problem with tape rotation and overwrite protection working correctly. I noticed if I create 4 scratch tapes on Friday and label them with a tape #, then assign 2 of those tapes to my 2 jobs, that the append time will start to count down. I set my append on my differentail backup to 6 days and my full backup to 7 days. I noticed which I thought that the documentation states that the append time will only start once a backup job starts. Well that does not seem to be true. Once a tape is moved from scratch media to the job media, it looks at the date when the scratch tape was created and works off of that. So if I create a scratch tape on Friday June 14th and the Differentail job grabed it on Monday June 17th, it shows that I only have 2 days left to append instead of 5 days. Why is this happening??
 
The documentation assumes that the only way media will be placed into a media set is by a BE job running and not by the user manually moving the tape into it. That's why you should never move media into a user media set manually, Only move media out of a user media set into a system media set (retired, scratched, etc.)

The overwrite/append time for a piece of media (tape) is set by the "media set" and not the actual backup job.
 
Scanner,

If I create 5 scratch tapes all today June20th. And I have a differentail backup set to append for 5 days. On Monday it grabs the first available scratch tape and for the next five days writes to it. Now on the following Monday which would now be a new 5 days will the differentail job go and grab a new scratch tape?? If so will it append for 5 days or will it compair the date that I created the scratch tapes and see that they are 5 days old???
 
The tape used by the second weeks backup job will depend on your overwrite settings (overwrite scratch media before/after recyclable media in targeted media set).

If your job is configured to use recyclable media first then it will look at the media set for the following (in this order):

1. media that has no overwrite protection (light blue, essentially the same thing as scratch media)

2. media that still has "append" time remaining

The "clock" starts on the overwrite/append settings at the moment that a backup job registers the use of the tape (basically as soon as you can see the tape label in the job log).

So let's say you import two new tapes. The first one is used the first week and has it's normal overwrite/append clock set. When the job starts on the second week and grabs the second tape the clock will start at that time (the beginning of the second week), regardless of when the tape was imported.

The media belonging to the first week (over the 5 day append limit) won't be written to unless the overwrite setting for that media set has expired.

If you place a 5 day append limit on a media set you are essentially locking out any changes to the tape from the 6th day on. At the end of the 5th day the tape can no longer be written to unless the overwrite setting has expired.

Does that help?
 
Thanks Scanner for the reply

It makes sence, but I do not believe my set-up is working the way I would hope. If I have my overwrite set at 12 weeks and append set for 5 days, then if I created 4 new scratch tapes on Friday and my job grabs a new tape on Monday, are you saying that is when the append time will start?? It seems that when I create the tapes that the job compairs the date of the creation date instead of the Job run date. I have noticed on Monday that when a new tape is used that the append time left after the job completes is only 2 days, which makes me think that since I created the tapes in scratch media on Friday that it counted from Friday to Monday which is 3 days.
 
The date used for the append clock is determined by the last job to "overwrite" it. Normally, if someone needs to append to a tape it is because there has already been something written to it previously. If you're trying to append to a tape that was never written to (in scratch status) then it's hard to tell exactly what the append clock will calculate.

For this reason I think the only stable way to do it is for the first logical job in the stream to be an overwrite job and all other jobs in that logical stream to be set for append.

The real key is getting the hang of logical job streams.

OK...let's use your rotation scheme as an example:

The user media set (we'll call it Media Set 1) has the overwrite setting of 12 weeks and an append time of 5 days.

I'm going start some assumptions here, so I hope you don't mind if they aren't exactly correct for your situation. I'm just using them for examples.

Since the append clock is set for a 5 day "alarm" then I'm going to assume that you're breaking your rotation weekly (Mon-Fri).

And since you are running 12 weeks overwrite protection I'm going to assume that you might be holding 12 tapes (one for each week of the rotation).

You could create a different backup job for each day of the 12 weeks, but that would take forever and not be very efficient.

On the other hand, you could create one job and run it every day of the same 12 weeks. This would be fast to create, but not very flexible.

In this case, I would see the most logical job stream as five backup jobs. One for each day of the week (Mon-Fri).

Once created, I would make sure that the first job in the stream (Monday) is set to overwrite the media. All other jobs (Tue-Fri) would be set to append.

Then I would schedule each job to run on it's respective day with a "once-per-week" job schedule. This will allow the same five jobs to be used for all 12 weeks of backup.

This would allow each tape to be written to five times a week and not be needed again until the 13th week after it is first "overwritten". Or alternately, on the 13th week you could send it offsite for long-term archiving and import another brand new tape for use in the rotation.

Now let's say on a Friday (of week 0) you take two brand new tapes and import them into use by BE and the system assigns the labels 4MM000001 and 4MM000002. This is just to get ready for the rotation to start in week 1.

By default BE will send the new media to the scratch pool where it will be freely available (no overwrite/append protection) to whatever job calls for it.

On the following Monday (week 1) the first job will launch (let's say at 10pm). Since 4MM000001 is in the scratch pool, the job can immediately use that tape. As soon as the tape is allocated by the job, the clock starts on both the overwrite and append settings according to the media set that the job points to (in this case media set 1).

On Tuesday at 10pm the second job in the logical job stream launches. Since the job is set to append, it will check the append clock on the tape written to on Monday and see that there is still 4 days of append time remaining.

The same with Wednesday's, Thursday's and Friday's jobs.

Even if the tapes were imported for use on the previous Friday, the Monday "overwrite" job effectively resets the clock.

On the next Monday, 4MM000001 will no longer be available because the append clock has run out so Monday's job at 10pm will have to use the next tape in the rotation (4MM000002).

I hope I'm not confusing you more. Keep me posted :)
 
That's all well and good, but what if, like me, you had to run differentials for 7 days a week? We do fulls on Friday and run diffs Friday - Thursday. I have an 8 tape library. This week all the tapes filled up except for 2, which the current media set denied writing to last night. The media is set to None for append period so it should continue writing differentials until it is full. However, BE thinks the tapes are full and my jobs failed last night. How do I tell that the tapes are full???

A 6 day rotation period will not work for my particular situation because of the tapes filling up. For instance, one of my 35/70 GB DLTs in Veritas is shown as having 114,512.254 MB written to it!!! With a 35GB uncompressed capcity, how did Veritas write 114 GB to it??? This software is the worst, least intuitive crap I've ever encountered.
 
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