SQL Server Error : 16389, Communication link failure

SQL Server Error : 16389 Details

SQL Server Error: 16389
Severity: 20
Event Logged or not: No
Description:
Communication link failure
Severity 20 Description:
Indicates that a statement has encountered a problem. Because the problem has affected only the current task, it is unlikely that the database itself has been damaged.

 

Waiting for SQL Server to recover database ‘msdb’… [298] SQLServer Error: 16389, Communication link failure [SQLSTATE 08S01] (ConnCheckIfDBIsOnline) [298] SQLServer Error: 10004, Communication link failure [SQLSTATE 08S01] (ConnCheckIfDBIsOnline) [298] SQLServer Error: 16389, Communication link failure [SQLSTATE 08S01] (ConnCheckIfDBIsOnline) [393]

While checking SQL Server Agent Log errors below

[298] SQLServer Error: 16389, Communication link failure [SQLSTATE 08S01] (LogToTableWrite) [298] SQLServer Error: 10004, Communication link failure [SQLSTATE 08S01] (LogToTableWrite)

Reading sql server error log location from SQL Query

Identifying SQL Server Error Log File used by SQL Server Database Engine can be done by reading SQL Server Error Logs. DBA can execute the XP_READERRORLOG extended stored procedure to read the SQL Server Error Log and search for its location used by the instance of SQL Server.

USE master
Go
xp_readerrorlog 0, 1, N'Logging SQL Server messages in file', NULL, NULL, N'asc'
Go

For other ways to read and find error log location please our artcile https://sqlserver-dba.co.uk/error-log/sql-server-identify-location-of-the-sql-server-error-log-file.html

Solution for Resolving the Error

The main issue, according to our findings, is the I/O latch. The server’s average CPU utilisation is 40%, and the SQL server spends the majority of its time waiting to read from the disc drive.

Antivirus software also scans the database files on a regular basis.

TCP Provider: [298] SQLServer Error: 121, The timer on the semaphore has run out. 08S01 [SQLSTATE]

Should I contact the network team about the connectivity issue or the storage team about the slowness of reading from the SAN?

You should look at the SQL Server log to determine why msdb or any other database was recovering in the first place.  Most likely your server did not shutdown properly during the patching reboot.

We need  to check SQL agent log file.  It seems its not started successfully or there is some issue with msdb for this error.

Recall something similar with some RTM release in SQ 2012

SQL Server Error Code and solution summary

SQL Server Error: 16389 
Severity: 20
Event Logged or not: No
Description:
Communication link failure