DSSU reporting 129 with free disk space

[Altria92]

Hello,

I seem to be getting disk full on my DSSU, even though ther appears to be free space. I have incrased the low water mark (from 80-95) but I am still encountering the error. Also, unless i am wrong the low water mark specifies a threshold of space needed before triggering the 129 error According to my calculations 88 % out of the 95% percent is consumed and the high watermark is set to 98%. Therefore there should be a trigger for disk space.

[Marianne]

Not sure I understand why you increased the Low water mark?

When High water mark is reached, NBU will free space until the Low water mark is reached (if images have been successfully staged).

So, a Low water mark of 95%  and a High water mark of 98% means that cleanup will start when the disk space reaches 98% and stops when it gets to 95%. Does that leave you with enough space for new backups?

What is your volume size? How much data on the disk? How much space is required for new backups?

Please also mention your NBU version and OS.

[Altria92]

It is version 7.1 on Win2k8 R2

I have reset the low water mark back to default (80%). I dont think I had a clear understanding of its purpose. Thanks for the clarification.

All the backups have a 1 week retention (lowest that i can see). I am actually not using diskstaging but rather having storage kept as tapes rotate offsite (another policy running). Therefore backup data is not being deleted. Is there a way that it can be overwritten, so only the newest data exists?

There should be enough disk space to complete the backup job. The total space is 2 TB with 300 GB free. yet the backup stops somewhere halfway into the job (NDMP). I suspect that it running out of calculated space needed for the backup as opposed to anything that may have been written. This is probably the reason that I do not see the free space volume decrease.

I tried to expire some duplicate jobs listed but I would still like to find a way to overwrite data, or shorten the retention.

[Marianne]

Low and High Water marks are only applicable when Disk staging is used. Only duplicated backups will be cleaned up or when they naturally expire.

Not sure why you have separate policies for disk and tape?

If you configure DSSU, your schedules will have retention period that you configure for the tape backups. You will have one backup running to disk first, then duplicated to tape at the time that you configure in the staging schedule. When high water mark is reached, the oldest backups already duplicated to tape will be deleted.

You can read more about DSSU (Disk Staging Storage Unit) in chapter 12 of NBU Administrator's Guide for Windows, Volume I  http://www.symantec.com/docs/DOC3653

[Amit_Karia]

The way you have configured DSSU, defeats the purporse of having a DSU , unless you have really configured disk staging i dont see any other way you can expire images from NBU.. you can either find images with multiple copies and delete them manually or write a script to do that for you..

Another question , how have you configured NDMP backups to run on DSU.. If you have NDMP drives configured, why not take backup on them

[Altria92]

I am running backups to tape as well as disk because I would like to have a nearline copy to do quick restores. I can not figure out a way to have the data sent to disk without being deleted oncce placesd on tape.

When you say duplicated, can that be done without deleting the data from the source?

[Altria92]

I am not sure by what you mean by how I have NDMP drives configured?

"how have you configured NDMP backups to run on DSU"

I have selected basic disk as storage unit. Also some backups reuire disk as opposed to tape. For example, to perform granular recovery backups I have to place backups on disk (or so I am led to believe)

[Marianne · Accepted solution]

Forget about NDMP. Please go read the section of the manual that I referred to above.

With disk staging you do ONE backup. The disk images are then duplicated to tape at the time that you define in the DSSU schedule. The duplicated images stay on disk for quick restores. As I've explained in my previous post, disk images are cleaned out when they naturally expire OR when the disk runs out of space (actually when it reaches high water mark). In that case, the oldest duplicated images will be cleaned out until low water mark is reached.