Thoughtsofanidlemind's Blog

Tag: Database Availability Group

  • Oooh… that’s some copy queue length!

    The Database Availability Group (DAG) is probably the best Exchange 2010 feature from both an impact and technology perspective. Microsoft took a really good decision by not limiting the DAG to enterprise editions of Exchange, even if you can only mount five databases on a server (counting both active and…

  • On the naming of DAGs

    Most Exchange administrators, even those who don’t have much hands-on experience with Exchange 2010, are now aware that the Database Availability Group (DAG) feature is built on Windows 2008 failover clusters. Exchange 2010 does an excellent job of hiding the complexities of Windows clusters and in normal operation you aren’t…

  • One or two NICs?

    During the development of Exchange 2010, Microsoft originally required that any mailbox server participating in a Database Availability Group (DAG) had to be equipped with at least two NICs (Network Interface Controllers). One NIC handles “MAPI” or client traffic; the other handles the replication traffic generated by Exchange to keep…

  • Thoughts on lagged database copies

    One of the best things about delivering training to smart people is the questions that they pose after you introduce a topic. During the recent Exchange 2010 Maestro seminars that Paul Robichaux and I delivered in Boston and Anaheim, I took the lead in talking about the Database Availability Group…

  • Odd seeding behavior for an Exchange 2010 database copy

    I run a virtual Exchange 2010 environment on my HP Elitebook 8530w laptop (8GB memory, SSD for the VM files). Usually things run along without a hitch but sometimes the USB connection to the SSD experiences a mild panic attack that causes it to disconnect from Windows. At that point…

  • The meaning of events 4113 and 4114 to Exchange 2010 SP1

    One of the lesser discussed updates included in Exchange 2010 SP1 is the addition of database redundancy monitoring by the Microsoft Exchange Replication service. This occurs for databases that are in a Database Availability Group (DAG) and is intended to ensure that each replicated database has sufficient healthy copies to…