NBU 6.0 MP4 - backing up large mount point with small files

[kimleong]

Hi all,

I'm on NBU 6.0 MP4, and when backing up a Tru64 client with a large mount point, I always end up with error 41. Have already tried various settings in bp.conf of the client, namely:

CLIENT_CONNECT_TIMEOUT = 3600
CLIENT_READ_TIMEOUT = 3600
BPSTART_TIMEOUT = 3600
BPEND_TIMEOUT = 3600
DO_NOT_RESET_FILE_ACCESS_TIME = YES
LIST_FILES_TIMEOUT = -1
SLAVE_CONNECT_TIMEOUT = 300

but still I'm getting error 41s. The problem is always with a particular mount point, which is about 12Gb in size with about 4.4 million files.

Let's say the mount point is /abc, is there any way to get NBU to perform multistream backup of directories in the mount point? I've tried something like this in the backup selection list:

/abc

NEW_STREAM

/abc/dir/dirA

NEW_STREAM

/abc/dir/dirB

NEW_STREAM

/abc/dir/dirC

The problem is the line /abc will also backup items in dirA, dirB and dirC, making it a duplicate backup. Is what I'm trying to do possible in NBU?

Thanks in advanced!

[Stumpr2]

Check to see if any of them is an extremely large file. You may have to split it up like you were saying to find out. Divide and conquer.

[sdo]

If the client is a plain client then CLIENT_READ_TIMEOUT is relevant on the media server that the client is sending its data to (over the LAN).

If the client is a SAN media server (i.e. a super client, saving itself directly to the SAN, and thus no LAN traffic), then CLIENT_READ_TIMEOUT is relevant on the client/SAN-media-server.

Is your client a plain client, or a SAN media server?

[kimleong]

Hi all,

It's a plain client only. So I need to set CLIENT_READ_TIMEOUT on the media server instead.

What about the divide and conquer strategy? How can I tell NBU to backup

/abc

/abc/dira <-- large number of files here

/abc/dirb <-- large number of files here

and yet avoid dira and dirb being backed up under /abc? (the mount point is /abc)

Thanks!

[Stumpr2]

is it possible to have only directories at the mount point level?

can you mkdir /abc/newdir

mv /abc/* /abc/newdir

/abc/newdir

NEW_STREAM

/abc/dir/dirA

NEW_STREAM

/abc/dir/dirB

NEW_STREAM

/abc/dir/dirC

[kimleong]

Hi Bob,

Thought about that before, but will be difficult to get downtime to do such migration. It will also be a nightmare to perform the migration as even an ls -l command is super slow.

I'm trying to set the CLIENT_READ_TIMEOUT to a larger value on the media server to test.

Thanks.

[Stumpr2]

Have you investigated "Advanced Client" Flashbackup option?

[Stumpr2]

here is a technote about flashbackup

DOCUMENTATION: How to configure backup for maximum throughput when a volume or folder contains millions of small files.

http://support.veritas.com/docs/275912

[sdo]

Won't:

/abc/

...only backup files in that folder only, and not traverse downwards?  Can anyone else confirm?

Also, you might like to take a look at:

Clarification of the use of wildcards in a policy's file list:
http://seer.entsupport.symantec.com/docs/275578.htm

Message Edited by sdw303 on 08-08-200702:00 PM

[J_H_Is_gone]

I also have some large file systems that I perfer to break up into smaller jobs.

i have a policy for them where I state in the files to be backed up.

New Stream

E:\a*

E:\b*

E:\c*

New Stream

E:\d*

E:\e*

New Stream

e:\f*

making sure I get all of the alphabit ( in case new dirs are created)  I break the New streams up into groups where I might not have any a* or c* but I do have a b*  - this way I don't get the error that no files were found.

I also limt the number of jobs this server can run at once ( 2 or 3 depending on my network speed for that server)

[kimleong]

Hi all,

Firstly, thank you so much for all the replies and sharing. To answer some of the points raised in the past few posts:

1. The technote on flashbackup is for Windows client. My problem is with a Tru64 client. Would a similar feature exist for Tru64 clients?

2. Including /abc will backup everything under it, because /abc is a mount point. Nothing else below it is a mount point, they are just directories with many many small files.

I've tried the wildcards, but found it very tedious and can leave 'cracks' where some files end up not being backed up if the wildcard do not cover all possible filenames/directories.

I'm still waiting for the backup, if it completes then I think I will just go with increasing CLIENT_READ_TIMEOUT on the media servers.

Thanks for all the posts!

[sdo]

Hi Kim, I just tried a test in Windows, and the same should be true in Solaris, and I used:

D:\Test-3\*

...and it did not traverse sub-folders.

Whereas:

D:\Test-3\

...did save sub-folders.

Could you not try?

/abc/*

...to only select files in that folder, but not any sub-folders and files.,

Message Edited by sdw303 on 08-08-200708:50 PM

[kimleong]

Hi SDW303,

Thanks for the tip - I understand what you mean now. My apologies for misunderstanding your earlier post. I think it should work as well.

To all,

I've managed to get the backup to complete. Total time taken for that large mount point:

6 hours 10 mins

12GB of data, 4.4 million files

That's a very slow ~500KB/s :)

Thanks for all who gave suggestions. The resolution was to increase the CLIENT_READ_TIMEOUT on the Media Server.

[sdo]

What value did you use?

Did you try any other values?

[kimleong]

I increased it from 300 to 3600 - sure to work! :)

Now I have lowered it back to 900 and will test. If it times out again, I guess I will have to increase by 300s and test.

[sdo]

Thanks, I'm sure many would like to know the final resting value

[Stumpr2]

1. The technote on flashbackup is for Windows client. My problem is with a Tru64 client. Would a similar feature exist for Tru64 clients?

Yes, please don't be too quick to rule out this option. Netbackup catalog contains a line entry for each file no matter what the size of the file is, and millions of lines for each backup will create a large catalog. Especially when you start to take in the idea of retention. In any case be prepared to explain to management the reasons for you backup solutions. Talk this option over with your reseller/sales support engineer.