Steps Details for DR activities

Please find the below steps for the DR activities.

As we all know that DR (Disaster Recovery) activities occur during an outage and it is confirmed that we can’t bring back the production site in a stipulated time. So this case we will proceed with DR.

In some case we will be planning the DR activities as part for the DR Drill.

These activities can be divided among two steps

A) Failover to DR   B) Failback to primary site.

A)     Failover to DR

1)      Update DNS Record:- Update DNS record and point it to DR DC load balancer from Primary DC

1.1)  Dependencies:- Changes performed on DNS servers close to end user, to reduce replication time

1.2) Time in Minutes:  Thirty minutes to perform the activity.

1.3) Country-Specific Detail - < Country > :

Update outlook.doamin.com(country wide LB details)  DNS record from :  primary (eg.192.168.1.1) to  DR (192.168.1.2)

2)      Verify whether alternate File share witness is accessible:

Remote desktop connection to file share witness server and verify whether witness share is present

2.1) Time in minutes: 15 minutes.

2.2) Country-Specific Details: Login to the server and check that witness directory is available and share is accessible.

              3) Stop DAG:-Stop DAG using following command in Exchange powershell

              Stop-DatabaseAvailabilityGroup -Identity DAGcc0x -ActiveDirectorySite PrimaryADSiteName –ConfigurationOnly

3.1) Time in minutes: 15 minutes

              4) How to restore DAG in DR site:

              Restore the DAG services in DR site using EMS  command

     Restore-DatabaseAvailabilityGroup -Identity DAGcc0x -AlternateWitnessServer ServerName -AlternateWitnessDirectory C:\Witness

                    4.1) Time in Minutes: 30 Minutes

        5) Verify Mailbox database status:

    Verify whether DAG has been activated on the DR Data center: -

 Get-DatabaseAvailabilityGroup -Identity DAGcc01 –Status

Verify whether all mailbox databases are mounted using cmd:-

 Get-MailboxDatabase DAGDE* -Status | ? {$_.Recovery -eq $false }  | Ft Name,Server,Mounted

Verify whether if content indexing has failed on any database:-

Get-MailboxDatabase | ? {$_.Recovery -eq $false }  | Get-MailboxDatabaseCopyStatus | ? {$_.ContentIndexState -eq "Failed" }

          5.1) Time in Minutes: - 45 minutes

 6) Verify Load balancer Connections: -   Verify active client connects through Network Load balancer which is in DR Datacenter

7) Verify the client side connections: Verify the client side connections by doing the outlook connectivity checks etc.

B)Failback to primary Datacenter

Verify Primary DC Exchange servers and dependencies:- Ensure that Exchange servers/Storage/Network and all other dependencies in primary Data center have been restored and all services are functional at optimal level

Verify whether primary witness server is accessible: Remote desktop connection to file share witness server and verify whether witness share is present Time in Minutes: 15 Minutes

Update DNS Records: Update DNS record and point it to Primary DC load balancer from DR DC Time in Minutes: 30 Minutes

Active  Directory replication:- Perform Health check for AD sites, Initiate AD site replication for all domain controllers between AD sites Primary and DR (15 Minutes)

DAG  Re-activation: Start Exchange 2010 DAG replication using following cmd Start-DatabaseAvailabilityGroup -Identity DAGname -ActiveDirectorySite PrimaryADSiteName Force DAG to set its quorum appropriately use following EMS cmd Set-DatabaseAvailabilityGroup -Identity DagName Verify whether DAG has been activated on the Primary DC :- Get-DatabaseAvailabilityGroup -Identity DAGcc01 –Status Move activation manager role to Primary DC using cmd :-Cluster Group "Cluster Group" /MoveTo:PrimaryDCMbxServerName Verify Activation manager is set appropriately using cmd:  Get-DatabaseAvailabilityGroup -Status | fl Identity,PrimaryActiveManager Time in Minutes: 1 hr 10 Minutes

Verify Database and DAG status Verify whether quorum type has been set to "Node Mejority" use following cmd:  Cluster /Cluster:DAGName /quorum Verify whether all mailbox databases are mounted use cmd:-  Get-MailboxDatabase -Status | ? {$_.Recovery -eq $false }  | Ft Name,Server,Mounted Mailbox databases need to activated/mounted on appropriate servers, as per database activation preference use following cmd with script :RedistributeActiveDatabases.ps1 -DagName DAGcc01 -BalanceDbsByActivationPreference –ShowFinalDatabaseDistribution Verify whether if content indexing has failed on any database: Get-MailboxDatabase | ? {$_.Recovery -eq $false }  | Get-MailboxDatabaseCopyStatus | ? {$_.ContentIndexState -eq "Failed" } Time in minutes: 1 hr and 15 minutes

Verify client  side validation: