SCCM WSUS Synchronization failed

Error in wsyncmgr.log:

Sync failed: LocalDBOtherError: SqlException: Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding.~~at Microsoft.UpdateServices.DatabaseAccess.DBConnection.DrainObsoleteConnections(SqlException e). Source: Microsoft.SystemsManagementServer.SoftwareUpdatesManagement.WSyncAction.WSyncAction.SyncWSUS
 

Resolution:
Clean the WSUS and maintain WSUS.
 
Here are two methods that should be used to maintain a WSUS hierarchy:
Re-index the WSUS 3.0 Database

http://gallery.technet.microsoft.com/ScriptCenter/en-us/6f8cde49-5c52-4abd-9820-f1d270ddea61

Run the Re-Index monthly. This can be run in any order within the hierarchy since it simply improves performance of WSUS database.
 NOTE: In addition to the steps covered in the link above, the following changes may be required:

• If you are hosting the WSUS database (SUSDB) on a full SQL server instead of using Windows Internal Database (WIDS), you can simply run the re-index as a SQL query using SQL Management Studio
  
• On a Windows Server 2008 R2 server, you have to update the recommended command line to the following to get the script to work with WIDS:
  

sqlcmd -i WSUSDB.sql -S \\.\pipe\MSSQL$MICROSOFT##SSEE\sql\query -E -I

You also have to install the SQL Native Client and the SQLCMD utility from http://www.microsoft.com/downloads/details.aspx?familyid=d09c1d60-a13c-4479-9b91-9e8b9d835cdc&displaylang=en
Run the WSUS Server Clean-Up Wizard

• You MUST run the WSUS Server Clean-up Wizard from the bottom of the WSUS hierarchy to the top and NEVER from the top down.
• You should run the WSUS Server Clean-Up Wizard throughout the hierarchy on a monthly basis. To help with this effort, you may want to automate the wizard using any of the following:
• PowerShell script sample for accessing the WSUS API for the cleanup functions: http://gallery.technet.microsoft.com/ScriptCenter/en-us/fd39c7d4-05bb-4c2d-8a99-f92ca8d08218
• Sample tool that handles the WSUS Cleanup wizard functions and offers a method to call the WSUSDBMaintenance script which can be useful if you run it as a scheduled task from the bottom of the hierarchy to the top on a monthly basis: http://wsus.codeplex.com/releases/view/17612

How to Run WSUS Cleanup Wizard:
 To run the Server Cleanup Wizard

In the WSUS administration console, select Options, and then Server Cleanup Wizard.

1. By default this wizard will remove unneeded content and computers that have not contacted the server for 30 days or more. Select all possible options, and then click Next.
2. The wizard will begin the cleanup process, and will present a summary of its work when it is finished. Click Finish to complete the process.