Have you determined the times that you are getting these peaks? I think there could be number of things going on here , one of which was mentioned - snapmirror running simultaniously. I would also check the time this is happening. If the you could find a pattern, this could help you narrow it down to what is running at the time.

-----Original Message----- From: owner-toasters@mathworks.com [mailto:owner-toasters@mathworks.com] On Behalf Of Holland, William L Sent: Tuesday, November 14, 2006 9:12 AM To: toasters@mathworks.com Subject: RE: SnapMirror Bandwidth restrictions

Take a look at Adjusting the TCP Window Size in http://now.netapp.com/NOW/knowledge/docs/ontap/rel705/html/ontap/onlineb k/mirror6.htm It can help you determine the proper setting based on your network needs.

-----Original Message----- From: owner-toasters@mathworks.com [mailto:owner-toasters@mathworks.com] On Behalf Of Davies,Matt Sent: Tuesday, November 14, 2006 7:58 AM To: Glenn Walker; toasters@mathworks.com Subject: RE: SnapMirror Bandwidth restrictions

Glenn,

The snapmirror.conf file is showing 1000 as the limit. Which should equate to just under 8Mb/s

Overall the rate does average out for the snapmirror jobs to be below 1000KB/s

There was only one snapmirror running at the time of the test I carried out to confirm the rates.

Matt

-----Original Message----- From: Glenn Walker [mailto:ggwalker@mindspring.com] Sent: 14 November 2006 12:47 To: Davies,Matt; toasters@mathworks.com Subject: RE: SnapMirror Bandwidth restrictions

I assume that the snapmirror.conf file is showing 1000 as the limit? This is in KB (kilobyte), not kb(kilobit).

Are you sure that there aren't multiple mirrors running simultaneously?

Glenn

-----Original Message----- From: owner-toasters@mathworks.com [mailto:owner-toasters@mathworks.com] On Behalf Of Davies,Matt Sent: Tuesday, November 14, 2006 5:40 AM To: toasters@mathworks.com Subject: SnapMirror Bandwidth restrictions

Hi,

We have noticed that when a snapmirror runs between our filers with a maximum transfer rate of 1000 KB/s, we are seeing peaks of traffic of around 24Mb/s.

This has been confirmed using ethereal, that it is the snapmirror traffic.

We have noticed that these peaks are causing excessive amount of dropped packets on the wan interface of the routers between all the site. we have tried a number of difference queuing strategies and bandwidth shaping, but the router cannot buffer all the packets during the peaks and starts dropping them. As we also use these links for both voice and video, we are seeing high jitter rates during these peaks, and need to do something about it.

We have a mixture of FAS250's and FAS270's all are showing the same problem

Has anyone else experienced this ? Or does anyone have any ideas.

Cheers

Matt