Unable to cycle error log due to lock that will not clear

Question

Hello,
Currently I'm having an issue with cycling the error log on two SQL Server Instances because the file is being used by another process. Simple I know but, when you try to kill the SPID it becomes hung and we are forced to restart the instance, which I want
to avoid at all costs. To give you some background we use sqldm for our monitoring of the databases and received a message that our Error log reached its max size threshold and to cycle the error log. When I executed exec sp_cycle_errorlog I'm told the following
message:
Msg 17049, Level 16, State 1, Procedure sp_cycle_errorlog, Line 9
Unable to cycle error log file from 'J:\MSSQL10.SQL6\MSSQL\Log\ERRORLOG.1' to 'J:\MSSQL10.SQL6\MSSQL\Log\ERRORLOG.2' due to OS error '32(The process cannot access the file because it is being used by another process.)'. A process outside of SQL Server may be
preventing SQL Server from reading the files. As a result, errorlog entries may be lost and it may not be possible to view some SQL Server errorlogs. Make sure no other processes have locked the file with write-only access."
DBCC execution completed. If DBCC printed error messages, contact your system administrator.
Then I ran the following query in instance A and found that sqldm had a active process.
SELECT *
FROM sys.dm_exec_requests a
OUTER APPLY sys.dm_exec_sql_text(a.sql_handle) b
WHERE session_id > 50
and session_id <> @@spid AND( text = 'xp_readerrorlog'  OR  text = 'sp_cycle_errorlog')
ORDER BY start_time a
Like I said before when I kill the SPID it became hung and remains in a rollback state (the process is not rolling back). My co-worker had this issue before on this same instance and contacted Idera for support, here was their response "The development
team provided an update regarding this case. After reviewing the code, SQLdm only reads the SQL logs information in each collection and does not lock this resource. Given the behavior that you described,  this could be a problem of SQL Server 2008"
I believe they're right because we're only seeing this in these two instances. All other instances using sqldm are not reporting this problem which leads me to believe it is MS SQL Server causing it. This is where I'm stuck and that is trying to find out why
there is a lock on this file and for what reason. I used Process explorer yesterday to search for any processes that are using ERRORLOG through the Find DLL and Handle window and there were mulitple processes touching this file. When I looked today I'm seeing
now locks for this file and I still cannot cycle the error log. I ran the slect query above I'm still seeing sqldm SPID in both instances. I'm curious to see if anyone else has had this issue before whether they used sqldm or not. Any information will be helpful
in tracking this issue down.
Thank you in advance.
Process Explorer Search Results
Instance A
Instance B

Answer 1

Hi,
Generally, I use Process Explorer to find out which process is blocking the SQL Server from cycling the error log file. Open search box for ‘errorlog’ or dentify the entries with Handle or DLL as ‘your error log path’. There could be two
or more processes relating to that. One of them should be ‘sqlservr.exe’, and the others should be the culprits. Verify the process, and try to terminate it and then you should be able to run the stored procedure ‘sp_cycle_errorlog’ to cycle the
error log without restarting the SQL Server.
According to the images, there is no process found. I suggest you start the monitor and launch procexp.exe tool again and see if it makes any difference this time. If still no progress, I think you cannot avoid restating.
Thanks.
Tracy Cai
TechNet Community Support