Remote snap shot ( copy )

[Bryan McMullan]

May be a worthless question, but were the volumes restriping/resyncing during the remote snapshot?

If so, then you are probably correct in that your admin tasks are impacting performance. I've never seen it cause a problem here, but I'm running 50 nodes, so it may be different if you only have a couple.

[larry-cgb]

left it set a 4 for a week them moved both ends to 16 ( heard it was the new setting in 8.5 ) but as you see it speeds the remote copy up a lot. I attached the screen print. I remote copy once both ways every night. The new setting is the top one. I was hinted that this is fixed in 8.5 but not sure.

[Bryan McMullan]

I played around with the settings in my environment and I see what you are saying. My speeds never went down to 4/8k sec, but there was quite a difference.

I'm still waiting on a response from my SE on this as remote copy speed used to be controled by remote bandwidth, local bandwidth only controlled resync/restripe/rebuild speed. The horror that would come from the mouths of LHN support when it came to talking about the local bandwidth setting made it sound quite taboo to change the default (though we still did when needed).

[Bryan McMullan · Accepted solution]

I finally received notification back from my SE to confirm your findings.

Cutting and pasting the response*

Local Bandwidth of the target group will limit the remote copies between the two groups if Remote_Bandwidth > Local_Bandwidth. We do have plans to de-couple this behavior in a future release, however, for 8.5 this behavior remains. In 8.5 we did increase default Local Bandwidth to 16MB/sec. Key info is local bandwidth of the target group is the key so they could throttle up their DR siteâ s local bandwidth and not hurt anything.

End cut and paste*

So it looks like the speed can be adjusted by setting only the remote side local bandwidth rather than needing it on both sides. (Not sure if you had set only the remote side, or both sides.) I can confirm in testing it does work with remote side only.

This must have been snuck into the 8.x releases.

[larry-cgb]

I DR both site to each other. I will look for the script the changes the local bandwidth at night.