WAAS and DFS

[mlouis]

I have a customer that has been experiencing latency on an application that they have been running that launches from a CIFS file share at the home office over a 40msec WAN connection. From packet captures, we can see that the WAE is in fact optimizing the file read/writes for the files the application is calling but it still is sending the Query_Path_Info, etc calls to the origin server as would be expected for file coherency.

The question here revolves around DFS. The customer would like to place a DFS server in the remote office and run the application from the DFS server share. Will this help at all by mitigating the need to send the query packets across the WAN?

[Zach Seils]

WAAS is not intended as a DFS target, but rather to accelerate access to a DFS target across the WAN. As you stated, there are some protocol messages that will have to traverse the WAN to maintain coherency with the CIFS semantics. Most notably are the file open and close requests.

There is potentially some tuning we can perform to improve metadata caching performance. Is it possible for you to provide me a packet capture from the client when WAAS is in place and you are seeing sub-optimal performance?

Thanks,

Zach