Hi people,

What are the maximum data throughputs that Snapmirroring people are seeing across a WAN? Is anyone seeing 15-20+ Mbit bandwidth usage from a snapmirror data stream?

The reason I ask is because I have a dedicated 20Mbit Ethernet link between 2 filers and am only seeing a maximum of 6-8Mbit of that available 20Mbit being used by snapmirror.

Details;

1) No CPU or disk bottlenecking on source or target

2) Source is F880 target F820

3) 3 snapmirror streams at volume level

4) Approximately 30-60 Gb of data per volume is snapmirrored per day.

5) 20Mbit WAN is about 95% dedicated to Snapmirror. The rest is small ftp, http traffic etc.

6) ftp transfers have been tested between filers and these saturate the 20Mbit immediately

7) snapmirror.conf is set to transfer at 6am each day. Current kbs=10000. i.e. 1 transfer per volume per day. This is for Disaster recovery synchronization requirements.

8) No packets are being dropped on the switch interface.

9) Single 1000Mbit Interface on source filer, 100Mbit interface on target.

10) Neither interface shows saturation.

11) Unix clients only at both source and target filers. 98%+ would be NFS traffic.

Now, NetApp support informs me that even if I had a dedicated VLAN between filer interfaces across the 20Mbit, I cannot expect to see full utilization.

I do not believe this. Someone out there must be transferring large amounts of data across a WAN and have seen higher throughput.

If you are seeing higher throughput rates, what type of setup do you have? Things I am currently considering;

- multiple qtrees snapmirrored. i.e. more snapmirror streams results in more throughput

- multiple snapmirror transfers per day

- dedicated VLAN between source and target

Any expert advice here would be appreciated.

Thanks,

Aaron