CIFS issue with WAAS

binhtra · ‎12-14-2010

Hi,

Currently we have 2 WAAS, 1 in HQ and 1 in branch, both of them are inline mode and use software version 4.1.7.

Everything seem alright except CIFS. When we copy a file from branch to HQ or vice versa, response time between 2 point increase up to 300-400ms or even request time out (use ping command). We also can’t view the status and summarize of CIFS in WAAS central management. If we disable WAAS, connection come back normal with response time increasing 20-30ms when copying file.

Do you experience with any kind of this issue?

Thanks

mmalwatt · ‎12-14-2010

Hi Binhtra,

I have a couple of questions about your issue:

1. When your copying files from branch to HQ or vice versa are you seeing a slower transfer on the 2nd attempt than when WAAS is disabled?

2. Is this just isolated to CIFS or do you see the same problem with other applications/connection types?

3. Does the response time increase say when your doing a FTP download between these sites?

4. What is the utilization level of your WAN link while the file copying is being done? The way TFO works you might see delay of other types of traffic over the WAN (ping for example). This is expected behavior due to the nature of TFO optimization (Window scaling, Selective ack, Large initial windows, congestion management).

Here is a great doc which shows what CIFS would look like on WAAS when it is running in full optimization mode:

Cisco WAAS Troubleshooting Guide for Release 4.1.3 and Later -- Troubleshooting the CIFS AO - http://docwiki.cisco.com/wiki/Cisco_WAAS_Troubleshooting_Guide_for_Release_4.1.3_and_Later_--_Troubleshooting_the_CIFS_AO

Please check the details in this document to make sure that CIFS is configured and working as expected.

Post the outputs of these commands here if you need help to verify.

Cheers,

Madura

binhtra · ‎12-14-2010

Hi Madura,

Below are my answer:

1. When your copying files from branch to HQ or vice versa are you seeing a slower transfer on the 2nd attempt than when WAAS is disabled?

Slower transfer compare when WAAS disabled.

2. Is this just isolated to CIFS or do you see the same problem with other applications/connection types?

This is just CIFS, all other application are okie

3. Does the response time increase say when your doing a FTP download between these sites?

FPT is still okie, response time increase around 10-20ms. This issue only happen with CIFS.

4. What is the utilization level of your WAN link while the file copying is being done? The way TFO works you might see delay of other types of traffic over the WAN (ping for example). This is expected behavior due to the nature of TFO optimization (Window scaling, Selective ack, Large initial windows, congestion management).

For all testing, WAN load is alwayls 15-20%. We do a lot of test and it happen with all test so I don't think WAN's load is reason.

Thanks

Binh

mmalwatt · ‎12-15-2010

are you testing the FTP at the same time of day as when your testing CIFS? Does the ping response time change at different times during the day (eg. busy periods, after hours)?

It will probably be best if you open a TAC case so we can investigate this deeper. Please when you do put all the information you shared in this discussion to the tac case.