Hi, I recently started at a new company who have a DC running Windows 2003 Server. This server also runs SQL server and a couple of bespoke applications. Every so often sometimes twice a week the server will just stop allowing clients to connect to the server. Nobody can connect to the databases, file shares are not accessible and our applications stop working. The only way to return to normal is to reboot the server. My question is how do I go about trying to find out what is causing this. Granted it could be a 3rd party app but where do I start. There is nothing much the in the event logs, my feeling is the server runs out of reources maybe although task manager does not show this. There was an entry in Event Viewer saying the the server had run out of Non Paged Ram but I have only seen this once. I have added the NP Ram column to Task amager and nothing seems high. How would you guys go about trying to find this issue here? Thanks in advance

Hello, sounds like DNS problem. Please post an unedited ipconfig /all from the DC and a problem client.Best regards Meinolf Weber Disclaimer: This posting is provided "AS IS" with no warranties or guarantees , and confers no rights.

Hey Chris, It looks like there is too much running on the server. Can you also confirm if the server is x86 or x64 ? According to me the server during peak hours is running out of resources and giving you event id 2020 or 2019 . To find out the culprit its a slow process you would have to deploy PoolMon and find out which driver or program is taking up your memory. Once you know the program\driver you can either update it to latest version number from Microsoft or the 3rd party vendor causing it and then monitor your server periodically. There could also be a resource crunch issue where doing the peak hour activity the resources are genuinely running out. In that case upgrading Memory would be a good option. Let me know if this helps BR, Aresh Sarkari

Hi, Thanks for posting here. When this connectivity issue occurred , have you tried logon this server locally and did this server still live at that time ? You may test with disabling all third party services and all startup items to check if this issue persist. Please refer the link below to disable these items: Using System Configuration http://windows.microsoft.com/en-IE/windows-vista/Using-System-Configuration Thanks. Tiger Li Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Hi Meinoff, I'm not sure it is a DNS problem as when the issue happens, i am unable to ping the server even by IP Address. Thanks for you help

Hi Tiger Li, Thanks for posting back, I can go to the server room and log on locally to the console and the server would seem fine. If i restart the Server Service this sometimes resolves the issue. Its as if the server just stops responding to remote connections etc. I'm also unable to ping the server from pc workstation when the issue occurs. I have re-installed the backup agent software, and the anti virus client and I am yet to see if that helps at all. Latest Windows updates are installed, it may be an option to upgrade the physical memory in the server as mentioned by Aresh but would a server runnign out of memory experience these issues. And would restarting the server service resolve a memory issue? This is what is confusing me? Thanks for everyones help

Hi Aresh, Thanks for your help, I am learning towards a driver or process that is slowing consuming all of the resources. I have installed PoolMon on the server from the support tools, but If i'm honest I have no idea what the information displayed means or how to interpret it to find the offending driver. Do you know if there are any guides out there which could help me identify it? Thanks Chris

Chris, What backup software is installed on the server? Thanks!

Hi, Backup software is Symantec Backup Exec Agent version 11d. I have un-installed and re-installed the agent as I thought that might be the issue. Thanks Chris

The following KB should help you identify the highest consumer of Non paged pool http://support.microsoft.com/kb/912923/ Its a NPP depletion as you are getting 2019 events and has nothing to do with RAM, NPP is a critical kernel mode resource and you will see these kind of problems if its depleted. As its a sql server I believe you have the /3GB set in boot.ini, if you do not need it plz remove it adding the /3GB switch cuts down NPP by half (without /3GB: 256 MB with /3GB: 128 MB) I would suggest you to completely remove /3GB and Userva in C:\boot.ini and configure AWE for SQL, that way SQL performance won't be comprised and at the same time the server would have enough kernel mode resources. However, the above steps would ONLY help if its NOT a NPP leak, if its a leak, we need to find the tag which is leaking NPP from poolmon, you won't be able to find this information from task manager. In case you cannot remove /3GB from boot.ini, make sure that /USERVA=2970 and /BASEVIDEO is added in boot.ini (a reboot is required for the changes to be in effect) if there are multiple unused NICs on the server, disable it as a proactive step, update all the drivers and update antivirus app to the latest version as pool allocations are made by the drivers in kernel mode many a times its a buggy driver that might leak pool memory. Additional information: Memory Management - Demystifying /3GB http://blogs.technet.com/b/askperf/archive/2007/03/23/memory-management-demystifying-3gb.aspx Memory Management - Understanding Pool Resources http://blogs.technet.com/b/askperf/archive/2007/03/07/memory-management-understanding-pool-resources.aspx Please let me know if you have any questions. Thanks, MadhurjyaMadhurjya Bora OS performance Team, MSFT

Hello, as said before let's check the DNS setup as requested before.Best regards Meinolf Weber Disclaimer: This posting is provided "AS IS" with no warranties or guarantees , and confers no rights.

Hi Aresh, How can I mark this thread as answered? Thanks

Hello, as this is not a thread, instead a discussion you can't. But please proivde your solution, so anybody can benefit from it.Best regards Meinolf Weber Disclaimer: This posting is provided "AS IS" with no warranties or guarantees , and confers no rights.