Tuesday 24 February 2009

SBS 2008 System Partition Out of Free Space and WSUS Db Size

Our longest running SBS 2008 box has been up since we got our hands on the RTM bits last fall.

We left everything on the system partition to see what happens when the server starts to get choked for space. The system partition is has a capacity of 75GB that works out to being around 73.5GB of formatted space.

In SBS 2003, we would receive e-mail warnings about any partition that was running short on space.

On SBS 2008, the only time we would see that there was a storage problem was in the weekly Detailed Summary Report:


SBS 2008 Other Alert – Percent Free Disk Space

If the above gets missed, surely this one, also in the Detailed Report, would not:

09-02-24 SBS Storage - Exchange Error due to disk space

MSExchangeTransport 15006 Error:

… rejecting message submissions because the available disk space has dropped below the configured threshold.

The error logged may get missed too, but users would be on the phone to the help desk, or to the I.T. support folks to let them know that there was a problem with their e-mail not getting out once things really stall in Exchange!

The biggest culprit for disk space usage on the volume that was running short was:

09-02-24 SBS Storage - Move WSUS Data - 36GB

WSUS Data: 36GB

This particular SBS 2008 network has the SBS 2008 box, Windows Vista Business and Ultimate, Windows XP Pro SP3, and Office 2007 (delivered via GP) on it.

Users are running accounting applications and some other Line of Business Applications besides the regular Microsoft applications and Companyweb centralized data shares.

So, there is nothing really out of the ordinary here.

When searching through the logs, there are three places to find flags for the space problem in the event logs:

09-02-24 SBS Storage - FRS Log - NtFrs 13570

File Replication Service:

FRS has detected that the volume hosting the path C: is low on disk space.

Note the date and time of the above error: February 13, 2009 at 11:03AM.

09-02-24 SBS Storage - System Log - SRV 2013


The C: disk is at or near capacity. You may need to delete some files.

Note the date and time for this one: February 14, 2009 at 11:41AM.

And, the Exchange error:

09-02-24 SBS Storage - Exchange Error 15006


The Microsoft Exchange Transport service is rejecting message submissions because the available disk space has dropped below the configured threshold.

Note the date and time for this one: February 10, 2009 at 7:58PM.

For servers that are being put into production, the simplest thing to do is to create a couple of custom filters for Event ID 15006 via the App Log and Event ID 13570 via the FRS Log and attach an e-mail Task to them. As soon as one of the Event IDs appear in the Event Logs, an e-mail will be fired off to the indicated e-mail address.

In this case, the SBS e-mailed reports kept coming in until February 19. 2009 which is five days after the above Exchange Transport event. So, for volumes running short on space where the Exchange databases are located, a lot will depend on the amount of e-mail volume being handled by Exchange before things completely stall out. The higher the e-mail volume growth, the quicker the stall.

The fix in this case was to use the Move Data wizard in the SBS Console to move the WSUS data off of the system partition onto the data partition we have specifically for working data. Once that was accomplished, our C: partition had lots of space on it!

Disclaimer: No Users were hurt in the making of this experiment! ;)

Philip Elder
Microsoft Small Business Specialists

*All Mac on SBS posts will not be written on a Mac until we replace our now missing iMac!

Windows Live Writer


Absoblogginlutely! said...

36gb is a lot of data - and needs to be downloaded each time you set up a new wsus server. Have you had any experience with cloning a wsus server and data or populating one across the lan instead of from the internet? I've not worked out a way to do this yet and it's killing me and the bandwidth! to think about downloading this each time I deploy a server to a new client.

HandyAndy SBS-MVP said...

Take a look at codeplex for some prebuilt alerts http://www.codeplex.com/sbs

Absoblogginlutely! said...

Just a follow up on my own comment - I followed the instructions in the WSUS Deployment manual (pg 81 onwards) on migrating and unfortunately it doesn't seem to have worked. It pulled in all the updates that I currently had but lost the approval status.When I approve an update it then goes and downloads the files from MS - leaving me with another potential 36gb download :-(
I'll have to take another look to work out why it's failing.

Philip Elder Cluster MVP said...


Thanks for the pointer! :)


The solution is to have a home WSUS server that you tell your new servers to connect to for their updates.

It is in the WSUS settings to grab updates from an upstream server.

A registry hack for both XP and Vista will enable them to pull from WSUS as well. You can reset the registry once the updates are done.


Absoblogginlutely! said...

Yep - that is what was going to be my secondary choice of implementation. This'll work as long as the server is brought back to our office first though ;-)