Legato Networker on Sol 8 server Best performance using SDLT

[Lancbar]

I have a Ultra E 450 Solaris 8 server running Legato Networker. I am using a SDLT tape device and I have configured the st.conf file as indicated by the manufacturer of that device. When I run a backup I am only getting about 6 mb/sec. I have heard that I should be getting around 11 mb/sec throughput. Anyone have any ideas as to why I am not getting the throughput I should be getting. Are there any other parameters I should play with to optimize my environment.

Thanks in advance for any input.

 

[ag100]

Hi,

First, which tape device are you using (hbn, cbn, etc..)? Depending on how the device uses compression (if at all), it can impact throughput.

Also, what kind of data are you backing up? Is the data you're backing up local, or going over the network.

Good Luck!

-ag100

 

[Lancbar]

Right now I am just doing a local backup using a Quantum SDLT. I tried both hbn and cbn and they both seem take the same amount of time for backups. The dataset I put together is a mixture of word documents, jpg, and mail arhived items. About 4 gigs worth just for testing. Do you know if there is any tunable parameters within solaris to optimize my situation.

Thanks for your response,

Lance

 

[ag100]

I don't know of anything within Solaris specifically.. How long does your backup take? Keep in mind the throughput is a max number, and you won't always see that transfer rate.

Also, one more question...

What directives do you have setup in the client profile in NetWorker?

 

[Lancbar]

I'm using manual backups for now. My backups with compression have been taking me about 9 to 10 minutes (6MB per second) with datasets of 4 gb. I tried doing a backup with no compression and my throughput doubled to 12. Now I need to figure out what I can configure to increase the compression throughput. My guess is that I need to find a way to allocate more memory to Networker. I'm pretty inexperienced with solaris so any suggestions would be helpful.

 

[ag100]

If the backup is local, and you want to see high throughput, use the cbn device and use standard directives, without compression. That's probably about the best you are going to do.. Anyone have any other thoughts?

In my environment, I have a mixed combo of hbn and cbn devices. How we allocate clients depends on data type, location and a variety of other factors.

Good Luck!

-ag100