We have a SQL 2005 sp4 32bit cluster in windows 2003 standard. Occasionally, Users were not able to make new connection including sa and SQL was very slow, after a while (can be 10 mins or hours), SQL stopped response and failed over, It happened pretty often. I saw the a lot following message in the log:
SQL Server failed with error code 0xc0000000 to spawn a thread to process a new login or connection. Check the SQL Server error log and the Windows event logs for information about possible related problems.
I did some monitoring during it happened, CPU usage is high, DISK IO is good, and did not see memory pressure. I found very high ASYNC_NETWORK_IO waits both in count and average wait time.
any suggestion or fix? I saw some other people had the same issues, but did not see right fix.