Dns Crash Every 12 Hours

[Jisamaniac]

I suppose the problem started when the users keep disconnecting randomly every now again, this past month. I checked the logs and the DNS disconnects every 12 hours at 3:00 AM and 3:00 PM, then the AD is looking for the DNS. The DNS, automatically restarts within 10 minutes, so downtime is not as bad as it could have been. The funny thing is the defragmentation happens EXACTLY at the same time. Defragmentation is turned off when I checked it by the old school way "C drive, right click, properties, etc."

SO my question is

1. Why would defragmentation cause the DNS to crash on a windows 2008 R2 server?
2. How do I go about fixing this/other suggestions?

Thanks for reading this.

 

[ICTCity]

I suppose the problem started when the users keep disconnecting randomly every now again, this past month. I checked the logs and the DNS disconnects every 12 hours at 3:00 AM and 3:00 PM, then the AD is looking for the DNS. The DNS, automatically restarts within 10 minutes, so downtime is not as bad as it could have been. The funny thing is the defragmentation happens EXACTLY at the same time. Defragmentation is turned off when I checked it by the old school way "C drive, right click, properties, etc."

SO my question is

1. Why would defragmentation cause the DNS to crash on a windows 2008 R2 server?
2. How do I go about fixing this/other suggestions?

Thanks for reading this.

Hi there,

This is an interesting question.

By default Microsoft add an automatic scheduler for defrag.

This process should be disabled and automatically enabled when you install "file server role". To disable this task:

Start>Administrative tools> task scheduler > Task Scheduler Library > Microsoft > Windows > Defrag


Defrag takes your DNS offline and I can't remember why, but I'm sure the reason was correct. Anyway, the fact that AD try to reach the DNS is workaroundable (can I use this word?!) by reading this Tech&Net's article:
http://technet.microsoft.com/en-us/library/cc732714(WS.10).aspx

Let me know if you need more help.

 

[Jisamaniac]

Excellent idea. I did try it but it did say the last time it was tried was "Never/2005." Any further ideas or need other details?

 

[ICTCity]

Excellent idea. I did try it but it did say the last time it was tried was "Never/2005." Any further ideas or need other details?

Mhhh Can you please post the complete log related to this error? I mean, DNS, System / Application.

Also post the result of:

dcdiag /a /q

Thanks

 

[Jisamaniac]

Actually looking for the log files you requested I stumbled upon it was the "Online Defragmentation." I did some research about it crashing and many people came up with the exact same errors as I did!

1. I have MSSQL 2008 running and if I turn off Online Defragmentation. Will it hurt my DBA?
2. How do I turn off Online Defragmentation?
3. Why would Online Defragmentation crash the DNS? Thoughts?

Thanks.

 

[ICTCity]

Actually looking for the log files you requested I stumbled upon it was the "Online Defragmentation." I did some research about it crashing and many people came up with the exact same errors as I did!

1. I have MSSQL 2008 running and if I turn off Online Defragmentation. Will it hurt my DBA?
2. How do I turn off Online Defragmentation?
3. Why would Online Defragmentation crash the DNS? Thoughts?

Thanks.

Online defrag permits to your system to defrag the DBA without taking offline the DB. Defrag means move files and if they're in use it can't be done. Here the meaning of ONLINE DEFRAG. Actually it will not hurt your DB, you can manually do a defrag regularly. I've not disabled defrag in my environment and I'm using shared storage (netapp).

To disable, take a look here:
http://www.pctools.com/guides/registry/detail/1309/