Saving files to File Share is extremely slow

Hi All, Has any one experienced any latency to accessing files shares using ZPA? It takes up to 30 second to save 60kb file. packet captures are inconclusive.

Did you check from Zscaler client connector towards Zscaler cloud and from your App connector towards Zscaler cloud that you don’t loose packets?

Hi @sdorckel
no packet loss. from ZAPP to app Connector it take 0.30 ms to connect. rest is a mystery

You can check in ZPA logs for the specific application you access which ZPA cloud broker was used.

Can you perform MTR test from your App connector towards ZPA cloud broker and the same MTR test from your Zscaler Client connector towards ZPA cloud broker?

@sdorckel sorry. support has done win mtr. 4 week ago. still not resolved

There are 3 paths involved with ZPA, client to service edge, connector to client service edge, and connector to application.

MTR across the 3 paths is relevant.

Typically you’ll want to have pcaps connector and client side to see if the client is not getting responses back from the connector in a timely fashion or the connector from the app. You should be able to see a delay between packets if you review rtt.

This latency becomes extremely painful. it takes upto 40sec to save excel file

Dear ZsCaler community, Still not able to resolve my slow file access latency over smb2 issues. Has anyone experienced the same issue. Saving a file stored at smb network Share is extremely slow it takes upto 40seconds or more. it has been more 8 weeks now zscaler support not able to resolve this. Any help or guidance will be appreciated

Are you using smb2 or SMB3.1 as vs 3 has improvements for WAN.

Hi @FirstVoid we are using smb2. i will enable smb3 and retest it. i will post the results

Just out of curisity can you check your MTU size and the latency on the path where possible? If you have latency above 30ms then you will see huge impacts with SMB. If you test with a sharepoint (HTTPS) or onedrive you will see a huge diffrence. SMB has never been good over SMB. This is why companies like riverbed exist.

@FirstVoid Connection from my laptop to Zscaler connector is 30ms. SMB3 not impreved anything

Strange question, do you have any DLP client running next to ZCC ?
I only ask because we had fileshare slowness with 30kb files which was caused by our third party DLP solution. Might not be related but worth checking.

Hi @murat. Now do you have any solution ? I found the same problem like you. If you can sloved it, please help to share me.

I have managed to reduce slowness from 40sec-50sec. to 10-12sec. it was antivirus. But 12 sec still long still investigating

1 Like

What i suggest maybe you could also check on the diagnostics for the broker that is connected to between your user towards the broker and from your broker to your App connector it might be due to the broker connection might not be optimal which is why you may face this issue.

We having been facing this same issue, specifically with the Miami III DC and lasts ~1.5 hours. So only our Florida users are impacted. Client machines would lock up and saving files takes ages for such small files. Local ISP isn’t the issue as when ZPA is disabled and switched to an alternate remote access solution, problem is not there.

It has happened 4 times now - twice in March 2021, last week and just today. It doesn’t affect all users so it seems to be related to a specific cluster node.

We have a high priority ticket open on this already and provided logs but support is still not able to identify the root cause. The was a patch installed on the Miami ZEN back in March which was due to a memory leak. Not sure if there are still issues going on which are not identifiable.

It’s very frustrating since the issue cannot be identified and nothing is posted on the Trust portal indicating a possible issue.

For those experiencing the slowness issues, what DC/Broker are you connecting to when the issue is occurring?

I have similar issue : opening XLS files from file sharing is extremely slow.
users are based in Canada, using SMB v2 file sharing server.
same issue with mac and windows users.
tested with 2008R2 and 2016 servers with same results.
The connector is local ( in the same LAN as the file servers )
Do you think that putting in place a local broker can solve this issue ?

We are experiencing the same issue. Our users are connecting to several different European broker. In the best cases we have only a delay of about 6 seconds when saving an empty Excel file to a share. In our tests we compared the performance to a traditional vpn where the files took less than a second to save. We also saw slowness when we just renamed files on a share which took a couple of seconds with zpa and was instant with vpn.

We’ve provided all requested information, logs and packet captures to the support and are since waiting for an answer. We also asked if a private service edge could help with this issue but the support could not answer that.

1 Like

Hello Murat , could you please confirm if the issue is only related to XLS files ? or also XLSX ?
can you send me your ticket ID with Zscaler support ?