Hi, Strange problem with the amo 1

[peeky1323]

Hi,

Strange problem with the amout of media used to backup data.

I have ARCserve 2000 SP4 on W2k Server SP3. HP 1/9 Autoloader ultrium 2 tape unit using 200GB tapes. I backup 11 remote servers using the Push agent (Also SP4). The total data for all 11 servers is 754GB. I put 7x 200GB (giving 1.4TB) tapes into the auto loader and it only got 1/2 way through the job because it used all 7 tapes.

We do not use software compression because it is enabled in the hardware. I noticed this in the log (note that 9/27/03 is the tape name).

28/09/03 21:22:16 2014 Backup K: to 9/27/03 sequence #2 session 25
28/09/03 21:22:16 2014 Source Directory: K:
28/09/03 21:22:16 2014 Back Up Session 25 on Media 9/27/03 8:57AM
28/09/03 21:22:16 2014 Approximately 20,252 files(s) 136,159,396 KB will be processed
28/09/03 21:40:16 2014 Next Media 9/27/03 ID 4828, sequence #3
28/09/03 21:41:16 2014 Please Mount Blank media to continue backup
28/09/03 21:41:16 2014 Resume backup operation.
28/09/03 23:57:19 2014 Next Media 9/27/03 ID 4828, sequence #4
28/09/03 23:57:19 2014 Please Mount Blank media to continue backup
28/09/03 23:57:19 2014 Resume backup operation.
28/09/03 02:12:29 2014 Next Media 9/27/03 ID 4828, sequence #5
28/09/03 02:12:29 2014 Please Mount Blank media to continue backup
28/09/03 02:12:29 2014 Resume backup operation.
28/09/03 07:24:34 2014 Next Media 9/27/03 ID 4828, sequence #6
28/09/03 07:24:34 2014 Please Mount Blank media to continue backup
28/09/03 07:24:34 2014 Resume backup operation.
29/09/03 08:02:51 2014 20252 files(s) 136396466 KB written to 9/27/03 @ 212,935 KB/min

Can anyone shed any light as to why it took 1.4TB worth of tape to backup 136GB?

Thanks in Advance,

Matt

 

[davidmichel]

First off the backup of the 136gb started on the sequence # 2 tape. So there are only three full tapes, #s 3, 4, and 5.

Second are those tapes the 100/200 tapes or the 200/400 tapes?

 

[peeky1323]

DavidMichel,

All the tapes are 100/200 tapes. Tape #2 only had 16GB of data from another machine on it so it was pretty much 4 tapes.

Thanks,

Matt

 

[davidmichel]

Ok so 100/200 tapes will hold anywere from 100 to a possibly up to 200gb depending on the amount of compression.

Take a look in the Media view of the database. Check to see the total mb written for all the full tapes, not just the ones from this job. Also check to see if there are any Soft Write Errors. To make sure they are full only look at tapes that spanned. So in this example look at all the tapes except the sequince number six tape.

Notice how tapes 3 & 4 only took about two hours to fill, and yet tape 5 took five. This might relate to the type of files backed up to each of the tapes.

It might be a case of streaming. If it is it might help to modify the buffers. For the Job Engine that can be done via the ARCserve Server Admin. For the Tape Engine use the sharemen utility found on the CD in the utilities directory. The idea is to make the buffers the right size so that data flows smoothly. If the buffers are too large or too small it will cause a delay and can lead to streaming.

 

[Cyklops]

Ultrium 2 can stream up to 70 MB/Sec, in your job only 3,5MB/sec is reached (213 MB/min). This is way too slow for Ultrium 2 devices which are developed for high perfromance networks like SAN's.
David is right about the streaming of tape drives, you can try to perform just a local testjob with a representative amount of data and see how the drive performs ( in this case you eliminate some possible bottlenecks).

regards

 

[peeky1323]

Thanks for the info I will give these a try.
I contacted CA support about this and 3 days later they sent be a patch to try:

http://support.ca.com/Download/patches/asitnt/QO41394.html

I think your answer is more spot on though. This is a problem that has only come about recently. We previously only required less tapes to back up this server (and anothe r 1 with the same amount of data)

I will post me results when I test them.

THanks,

Matt

 

[peeky1323]

Hi,

I just checked the Media stats on those tapes. These tapes all had the same amount.

No soft read/wrote erros
Total MB written: 43,617

Tapes from other jobs in the last few weeks (that backed up different kinds of data) also have well below the 100GB amount I would expect even if no compression had taken place. Out of the last 40 tapes used, less than 10 used over 100GB with the highest amount being 146GB. This was source files and mainly text so I would expect high compression.

I am doubtfull the patch they gave will work.

Do you have any advise on what changes in buffer size will do? I mean will increasing the buffer optomise ARCserve for larger files, and vise versa? I backup a multitude of file types in the same job ranging from 1,000s of small source files, to large software images of 4GB+ each.

Thanks,

Matt

 

[peeky1323]

Hi,

In case anyone is interested the patch CA gave me blew away my ARCserve system. I had to re-install SP4 over the top to fix it. After installing the patch I kept getting 1000's of "Unrecoverable Media Errors" when trying to backup anything. I replied the their email yesterday morning desparatly asking got help and they still havn't responed.

I am still having problems with tape capacity. The majority of the tapes are only getting 39GB?!? These are 100/200GB tapes.

If anyone has any further ideas I would appreciate it as I am drowning in tapes here

Thanks,

Matt