WSUS sync fails with HTTP 503 errors

During the SCCM 2012 Migration, as soon as we complete, we probably get this error where number of SCCM client is high.

Error on SMS_WSUS_SYNC_MANAGER component

Message ID: 6703
WSUS Synchronization failed.
Message: The request failed with HTTP status 503: Service Unavailable.
Source: Microsoft.UpdateServices.Administration.AdminProxy.CreateUpdateServer.

When you attempt to open Update Services on the WSUS server you receive the following error:

error: Connection Error
An error occurred trying to connect to the WSUS server. This error can happen for a number of reasons. Please contact your network administrator if the problem persists. Click the Reset Server Node to connect to the server again.

In wsyncmgr.log you will get the below error,

Sync failed: The request failed with HTTP status 503: Service Unavailable.


In this situation, the most likely cause is that the WsusPool Application Pool in IIS is in a stopped state, as shown below.

Also, the Private Memory Limit (KB) for the Application Pool is probably set to the default value of 1843200 KB.

If you encounter this problem, increase the Private Memory Limit to 4GB (4000000 KB) and restart the Application Pool. To increase the Private Memory Limit, select the WsusPool Application Pool and click Advanced Settings under Edit Application Pool. Then set the Private Memory Limit to 4GB (4000000 KB).

After the Application Pool has been restarted, monitor the SMS_WSUS_SYNC_MANAGER component status, wcm.log and wsyncmgr.log for failures. Please note that it may be necessary to increase the Private Memory Limit to 8GB (8000000 KB) or higher depending on the environment.

Access content directly from distribution point - SCCM 2012

Microsoft introduced the new content library, the idea is to save space by saving all files in a library but only save identical files once, and refer to the location for all other instances of the file. The idea is good, but it comes with a price. All content stored in the library must be extracted during installation. This slows down the deployment meaning all files will have to be downloaded by the client.

If you want to change this and store your content in a share, you can. Please be aware that this has a cost in disk space.

On all your content in the task sequence meaning packages, boot, images, drivers even the configuration manager agent, select “copy the content in this package to a package share on distribution points.”

At this point you will start to see package shares (eg smspkgc$) start to appear on the distribution points, just like they would in SMS & SCCM ‘07. Once all of the packages have had the above option enabled, open up your task sequence deployment (aka advertisement) and on the Distribution Point tab you will now see an additional option in your drop down box:

Of course you should have a think about and understand the effect this is going to have, for example this may used up to double the amount of storage space for each package on your DP as the files will be stored in the Content Library as well as the Package Share location.