Is it possible to speed up a Recovery?

[eeicai]

Hi there,

I need to restore the entire contents of a w2k server, 187GB in total. Our backup server is running Legato 6.2 over Windows NT and is reading from tape at an average of 2GB/hr but at this rate, it looks like Friday morning it will complete. Started it yesterday evening and it is now at 26GB.
Can anyone help me see if there are ways of speeding up the read from tape process?
Many thanks
C

 

[605]

In general the maximum speed will be the same as you achieved during the backup. However, if you use multiplexing, most likely you will not recover all save streams at the same time. Consequently, you should only have one backup (save) stream at a time to achieve that.

As 1MB/s will result in 3.600 GB/h the, your recover speed points to a structure of a lot of very small files. In this case the recover speed is very slow and could even be worse.

Not knowing anything about your configuration you could make some general decisions to prevent such situation;
- Do not multiplex data streams during the backup
- Use fast backup devices (file devices)
- Use raw or shnapshot backups (snapimage), if possible

 

[NWNinja]

Also, when restoring an entire filesystem, i always use saveset recover to avoid having to mark all the files when browsing. This slows down the initial start process.

Like 605 mentioned, the use of file devices are the best way to achive both fast backups as well as recovers. If you then clone/stage the data from disk to tape, this will be done with a parallelism/target session of 1 = no multiplexing and thus recovers from tape will be faster as well.