Intermittent file sharing connectivity from various clients to a Windows Server 2008 server

Issue

In recent weeks we have seen a number of cases with intermittent file sharing connectivity to Windows Server 2008 servers. I wanted to get this information out so that people who may be experiencing the issue won’t have to spend a lot of time tracking down the problem.

The issue generally manifests in one of two ways:

  • After a period of time Windows XP and Windows Server 2003 clients can connect to file shares on a Windows Server 2008 server but Windows Vista clients time-out.
  • After a period of time Windows Vista clients can connect to file shares on a Windows Server 2008 server but Windows XP and Windows Server 2003 clients time-out.

Network traces look similar in both cases. After the TCP 3-way handshake the client sends an SMB Negotiate Dialect but the server doesn’t respond.

Eventually the TCP session times out and is reset as seen in this example:

image

Resolution

Two things are currently known to address the issue:

  • Upgrading the NIC drivers is known to help but not completely resolve the issue.
  • In the cases we have seen so far, uninstalling anti-virus software has resolved the issue.

Most of these cases involved older anti-virus software versions but we have also seen the issue with current versions that are supported on Windows Server 2008.

While there is not currently a complete resolution, I hope providing this information will help some people identify this issue quickly so they can resolve it and minimize the disruption to their environment.

– David Pracht