Following a failover of our (Windows Server 2008) cluster, we started to encounter unexpected errors when BizTalk attempted to perform any tasks that required a distributed transaction, even though everything appeared to be running correctly: MS-DTC was running and we could DTCPing the BizTalk Server from the SQL Server (and vice-a-versa), so no issues with DTC; SQL Server was also running as we could connect to the instance via Management Studio and BizTalk could read the Management Database etc., yet DTC operations still failed with the following error:

Enlist operation failed: 0x8004d01c(XACT_E_CONNECTION_DOWN). SQL Server could not register with Microsoft Distributed Transaction Coordinator (MS DTC) as a resource manager for this transaction. The transaction may have been stopped by the client or the resource manager.

A severe error occurred on the current command.  The results, if any, should be discarded. (Microsoft SQL Server, Error: 8510)

It turns out that when clustered services are brought online, they must be started in a specific order, with the DTC service being started before SQL Server. If they are not brought online in this order, SQL Server fails to register itself and DTC transactions cannot be initiated, even though both the DTC and SQL service’s are running and everything looks correct.

Thanks to this forum post for providing us with the much needed pointer: http://www.ureader.com/msg/1142121.aspx.

This should only be a 30-45 min meeting and is open to all via Live Meeting. Hope you can join us and see this excellent tool in action.

Full details – including registration – are available on the SBUG Website: http://sbug.org.uk/forums/p/156/232.aspx#232.

I noticed an interesting quirk last night while trying to format a Guid into a string representation – by default, Guid.ToString() does not return an accurate representation of a GUID with curly braces. Hmmmmmm…..

Consider the following simple test, here we are instantiating a new Guid and before outputting the value to the debugger, we capture its value – note the curly braces at the end of the Guid:

If we let the test run its course, we get the Guid formatted as a string (using the default formatter) written to the debugger, but there are no curly braces:

After much head scratching and Googling, I decided to look at the MSDN documentation for the Guid.ToString() method – low and behold there are several format specifiers that can be provided to the ToString() method which determine the formatting provided to the resultant string. Using the format specifiers:

we get the desired output:

If no format specifier is used (i.e. we just Guid.ToString()), the default format is ‘D’ – no braces.

I received an interesting error today while setting up a new TeamCity build-server. When running the MSBuild Microsoft.Sdc.Tasks GAC uninstall task – GlobalAssemblyCache.GacHelper.Uninstall – I kept receiving the following error:

C:\Subversion\Trunk\BizTalk\Build\Common-Deployment\Common\Deployment-Cleanup.proj(59, 3): A task error has occured.
Message = Failed to uninstall CandidateMarks.Canonical, PublicKeyToken=1b76b267b587386b from the GAC. AssemblyName = CandidateMarks.Canonical, PublicKeyToken=1b76b267b587386b

at Microsoft.Sdc.Tasks.GlobalAssemblyCache.GacHelper.Uninstall(String name)
at Microsoft.Sdc.Tasks.GlobalAssemblyCache.RemoveAssembly.InternalExecute()
at Microsoft.Sdc.Tasks.TaskBase.Execute()

It turns out that the user attempting to uninstall or install assemblies to the GAC needs write permissions to the %systemdrive%\Windows\Assembly directory (as documented here and here). Adding that user to either the local computer Power Users or Administrators Group provides the necessary permissions and the above error is no longer an issue.

Ok, so I know that isn’t all that cold for some of you, but for the South East of England (when we barely get below -2 degrees in a good winter) thats pretty darn cold and certainly the coldest I’ve ever seen (but still not quite 1963!)

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I think that 2009 will be a fantastic year for the community with the introduction of BizTalk 2009, Dublin and the whole Oslo experience – plenty to get our teeth into.

For me, I have a few objectives and I feel that if I list them here, there is a chance of me actually acheiving some of them:

• Get onto the Microsoft qualifications ladder, including BizTalk 2006 R2, WCF and WF.
• Become a BizTalk MVP and attend the MVP Summit in 2009.
• Work on an enterprise ESB and EDI project.
• Get hands on with Dublin and Windows Azure.

and a few personal goals:

• Travel as much as possible, including a second trip to the US.
• Get rid of the belly fat, with a possible half-marathon if I can ever learn to run.
• Gain my PADI Rescue Diver qualification and dive Scapa Flow in Scotland.

I’ve been reading all about Azure and Oslo, but I’ve yet to read anything concrete about Dublin – are you guys picking up any detail on what it will offer? Have you seen any demos on actual usage?

Cheers, Nick.

Update: May have answered my own question with a bit more research: Darren Jefford and Maina Donaldson have good explainations over on their blogs.

VeriSign also maintained 100 percent uptime for the DNS system during the second quarter, as it has for the past decade. I think this must be one of only a handful of cases in the industry, given how elusive even 99.999% uptime is.

More info over at Data Centre Knowledge.

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