Automatic Reseed in Exchange Server 2013

In this blog we will be exploring some new feature introduced in Exchange Server 2013. Microsoft has introduced a new High Availability Feature “Automatic Reseed”. To simulate the scenario we have already created two member DAG.

Lets Explore

Figure 1 : Two Node Dag

To understand the concept lets first explore the new DAG properties.

Figure 2 : Data properties

In figure 2 we can see some attributes as “AutoDag” with various options. The option available is the default option and there are some customization required to ensure that Automatic reseed works the way you expect.

Old Story – In Exchange Server 2010 if a disk fails then the entire database fails over from active node to passive node. And if the same happens in passive node then you might end up replacing the disk and start with either full reseed or manual reseed based on the database size.

New Story -  In Exchange Server 2013 we have Automatic Reseed. So lets have a look at it how to configure the Automatic Reseed feature.

DAG Settings

In figure 2 we have to set below properties as per our requirement.

1. AutoDagDatabasesRootFolderPath : Default mount point for database.
2. AutoDagDatabaseCopiesPerVolume : Allows us to set number of database copies per volume.
3. AutoDagVolumesRootFolderPath : Default mount point for all volumes (Best practices is to have it in the root).

For more information on Best Practices on volume mount points please refer 280297.

Figure 3 : Folder Names Created in the root of C Drive.

In figure 3 Two folders are created for Volumes and Database.

Now first we have to create mount volume folders as shown below.

Figure 4 : Two directories for volumes

Now open disk management and we will create mount points using these two folders.

Figure 5 : Change Drive Letter and Paths

Figure 6 : Select Add

Figure 7 : Path

Figure 8 : Volume Mount Points Created

Figure 9 : Database Directory

Repeat steps 5,6 and 7 for database directory.

Figure 10 : Mount Volume for MDB1

Figure 11 : Comparing and Confirming Mount Volume.

Now lets create Data folder and Log File folder.

Figure 12 : Data folder and Log folder

In figure 12 when we create data folder and log folder. It must create the exact folders in E drive.

Figure 13 : Folders listed in E Drive.

Now Lets create database with the help of EMS.

Figure 14 : Create Database

Figure 15 : Created Successfully

After Creating the database mount the database. Post which add the database copy.

Figure 16 : Database Status

Lets test auto reseed.

Figure 17 : E Drive is offline.

In figure 17 E drive was taken offline forcefully to simulate the auto reseed functionality. In practical scenario it may be different.

Figure 18 : Status

Figure 19 : Auto reseed completed.

Note : To track the behavior in the background. You can refer the crimson log. Check “Seeding” on the source server where the drive has crashed. If the database is large it will take considerable amount of time to reseed.

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Happy Learning

Automatic Reseed in Exchange Server 2013

In this blog we will be exploring some new feature introduced in Exchange Server 2013. Microsoft has introduced a new High Availability Feature “Automatic Reseed”. To simulate the scenario we have already created two member DAG.

Lets Explore

Figure 1 : Two Node Dag

To understand the concept lets first explore the new DAG properties.

Figure 2 : Data properties

In figure 2 we can see some attributes as “AutoDag” with various options. The option available is the default option and there are some customization required to ensure that Automatic reseed works the way you expect.

Old Story – In Exchange Server 2010 if a disk fails then the entire database fails over from active node to passive node. And if the same happens in passive node then you might end up replacing the disk and start with either full reseed or manual reseed based on the database size.

New Story -  In Exchange Server 2013 we have Automatic Reseed. So lets have a look at it how to configure the Automatic Reseed feature.

DAG Settings

In figure 2 we have to set below properties as per our requirement.

1. AutoDagDatabasesRootFolderPath : Default mount point for database.
2. AutoDagDatabaseCopiesPerVolume : Allows us to set number of database copies per volume.
3. AutoDagVolumesRootFolderPath : Default mount point for all volumes (Best practices is to have it in the root).

For more information on Best Practices on volume mount points please refer 280297.

Figure 3 : Folder Names Created in the root of C Drive.

In figure 3 Two folders are created for Volumes and Database.

Now first we have to create mount volume folders as shown below.

Figure 4 : Two directories for volumes

Now open disk management and we will create mount points using these two folders.

Figure 5 : Change Drive Letter and Paths

Figure 6 : Select Add

Figure 7 : Path

Figure 8 : Volume Mount Points Created

Figure 9 : Database Directory

Repeat steps 5,6 and 7 for database directory.

Figure 10 : Mount Volume for MDB1

Figure 11 : Comparing and Confirming Mount Volume.

Now lets create Data folder and Log File folder.

Figure 12 : Data folder and Log folder

In figure 12 when we create data folder and log folder. It must create the exact folders in E drive.

Figure 13 : Folders listed in E Drive.

Now Lets create database with the help of EMS.

Figure 14 : Create Database

Figure 15 : Created Successfully

After Creating the database mount the database. Post which add the database copy.

Figure 16 : Database Status

Lets test auto reseed.

Figure 17 : E Drive is offline.

In figure 17 E drive was taken offline forcefully to simulate the auto reseed functionality. In practical scenario it may be different.

Figure 18 : Status

Figure 19 : Auto reseed completed.

Note : To track the behavior in the background. You can refer the crimson log. Check “Seeding” on the source server where the drive has crashed. If the database is large it will take considerable amount of time to reseed.

===================================================

Happy Learning

Upgrading Exchange Server 2013 DAG

In this blog we will be exploring one of the wonderful changes what we have in DAG. Upgrading DAG was never so easy. With the help of Crimson log we can monitor each and every step to understand what happened in the background.

Lets Explore

To test the behavior we have built a two member DAG.

Domain : MSEXCHANGETEAM.IN

DAG Name : E15-DAG

DAG Members : MBX1 & MBX2

FSW Owner : MBX3

Estimated time to complete : Depending on the network. If everything is planned then it should not take more than 4 hours. However since it’s a DAG then client should not be affected.

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In Exchange Server 2013 you can directly apply CU, since versioning issue is being removed. However as a best practices we will first begin with MBX3.

Before starting the setup we will collect some basics.

Figure 1 : Exchange Server Info

In figure 1 we have three servers with Version as 15.0 (Build 516.32).

In our scenario we will first upgrade MBX3.

Figure 2 : Readiness Checks

Note : I have skipped few screenshots. Since they are self explanatory.

Figure 3 : MBX3 Upgraded

In figure 3 if you see the build number has changed.

Now since we have the FSW upgraded. Its time to upgrade the DAG Members. Lets first see the Mailbox Copy Status by running the below command.

Figure 4 : Database Copy Status

To begin with we will start with passive copy server which is MBX2 in our scenario.

Figure 5 : MBX2 is showing as Service Down

Now while the upgrade is running the status will show as Service Down. The interesting point to note here is once the upgrade is over the database will automatically move to MBX2.

Figure 6 : Status

In figure 6 the database got moved automatically without manual intervention.

Figure 7 : MBX2 Upgraded

Figure 8 : MBX1 Upgraded

While MBX1 was getting upgraded and it completed successfully the below event ID will get generated in the Active Node i.e MBX2.

Figure 9 : Operational Event Logs

In figure 9, I have copied only one example of how the process works in the background. There are many interesting events to track and explore the new feature.

I have tried to keep the blog as short as possible. Since the steps are same what we have in the RTM version of Exchange Server 2013 Setup and they are self explanatory.

Note : In the entire process of upgrade not even a single clients were disrupted.

Exchange Server 2013 Rocks

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Happy Learning