Only windows 7 machines can always access shares on windows 7 server

I'm not sure if this belongs here or on serverfault, but I already have an account here so this is where I'll start.

In my office we have a development server running windows 7 pro or server 2008 (I'm not sure which as I don't personally have access, but I can find this out if it's important), with network shares for each of the current builds. We've always done it this way, but it used to be a windows server 2003 box.

Anyway - periodically the server starts refusing connections from xp/2003 boxes, and there are errors in the server log about something running out of space; however we've found that someone rdp'ing into the server and running net stop server, net start server, net start "Computer Browser" fixes the issue.

This however requires for someone with access rights to stop what they are doing and do this about 2-3 times per week.

Is there any way to solve this issue permanently? It seems obvious that there is an issue with the windows legacy network share, but is this a setup issue that can be solved, or if not is there a seamless workaround such as some way of monitoring the error log and restarting the service as soon as there's a problem?

Having checked it's Windows 7 Professional

OK I got the error message from the windows server log :

The server was unable to allocate from the system nonpaged pool because the server reached the configured limit for nonpaged pool allocations.

theheadofabroom

Posted 2011-06-15T10:12:08.610

Reputation: 167

Answers

Now that we have a full error message a quick Google search returns the following discussion on TechNet.

Apparently you need to tell Windows that you want to use the machine as a file server and that it should allocate resources accordingly. Set the following registry key to ‘1′: HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\LargeSystemCache

And set the following registry key to ‘3′: HKLM\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters\Size

After making these changes and restarting, I haven’t seen this issue arise again.

As always, edit the registry at your own risk. ;-)

N_Lindz

Posted 2011-06-15T10:12:08.610

Reputation: 557

It sounds like you are probably periodically exceeding the maximum 20 SMB connections that Windows 7 (older versions allow 10) allows. The solution is to upgrade to a server OS.

Keep in mind that users can make more than one SMB connection to the computer, so you may still be hitting the limit.

http://www.winsupersite.com/article/win7/windows-7-product-editions-a-comparison (search smb connections on the page)

KCotreau

Posted 2011-06-15T10:12:08.610

Reputation: 24 985

Windows 7, except for Starter if I am not mistaken, allows up to 20 connections. See this excerpt from the EULA: Device Connections. You may allow up to 20 other devices to access software installed on the licensed computer to use only File Services, Print Services, Internet Information Services and Internet Connection Sharing and Telephony Services. – bwDraco – 2011-06-15T11:20:12.317

Okay, Starter also allows 20 connections as well. – bwDraco – 2011-06-15T11:29:26.813

It looks like this is the problem - it's Windows 7 Pro. It won't be upgraded, you know what Technical Services departments can be like. Do you know any work-arounds? – theheadofabroom – 2011-06-15T13:26:49.203

@BiggAl Write a script and toss it in a scheduled task that will do your net stop server, net start server, net start "Computer Browser" command for you? Have it run in the middle of the night when the odds of someone using the system are slim? Just a thought. – N_Lindz – 2011-06-15T13:56:49.843

Hmm - if it's due to a 20 machine limit I'd say chances are slim - surely the connections would time out overnight? It's more likely that the randomness in occurrence is due to fluctuating usage patterns between departments. I stumbled across Half-open limit fix which looks like it would do the trick, but I'm not sure of the legality. Anyone? @N_Lindz @DragonLord

– theheadofabroom – 2011-06-15T14:09:49.387

Oh wait, it looks like this was a red herring @N_Lindz @DragonLord

– theheadofabroom – 2011-06-15T14:15:32.817

You guys were right, and I edited my comment to reflect the 20. – KCotreau – 2011-06-15T16:37:31.330

I found the solution here - Windows 7 Professional does not have a half-open limit, however when you have a large number of people connecting you can get the OS running out of cache for it.

theheadofabroom

Posted 2011-06-15T10:12:08.610

Reputation: 167