Wednesday, November 1, 2017

Recovering a database to its original location

As part of a recovery process, recovering databases by using DPM is an important task. While the procedure that follows provides the general steps for database recovery, when you recover a CPS feature, you must follow the feature's specific recovery steps as described in the “Recovering from management cluster component failures” section in the CPS Admin Guide.

1. In the DPM administrator console, click Recovery in the navigation bar.

2. In the Recoverable Data area, expand SQL Server, All Protected SQL Instances, expand the instance of SQL Server that hosts the database that you want to recover, and then select the appropriate database, as shown in the following image.

3. In the Recovery Points pane, select a recovery point by clicking any date and time in the calendar to see available recovery points. Dates that are shown in bold have active recovery points. To minimize data loss, it is important to choose to recover from the latest possible recovery point.

4. Click Recover in the Actions pane to launch the Recovery Wizard.

5. In the Recovery Wizard, on the Select Recovery Type page, select Recover To The Original Instance Of SQL Server (Overwrite Database), and then click Next.

6. On the Specify Database State page, keep the default setting of the Leave Database Operational option.

7. On the Specify Recovery Options page, leave the Network Bandwidth Usage Throttling and SAN Recovery settings without any changes.

8. On the Summary page, review your settings, and then click Recover.

9. After the recovery completes, click Close to close the Recovery Wizard.

10. After you recover a database, it must be synchronized by DPM. The protection status of this database will be Replica Inconsistent until you synchronize it as follows:

a. In the DPM administrator console, click Protection in the navigation bar.

b. Right-click the recovered database, and then click Perform Consistency Check.

c. In the Microsoft System Center 2012 R2 Data Protection Manager dialog box, click Yes to perform the consistency check.

Source of Information : Microsoft System Center

Tuesday, October 31, 2017

Recovering VMs to their original location

The following steps use the DPM administrator console to recover VMs to their original location:

1.Open the DPM administrator console, click Recovery, and then, in the Recoverable Data pane, browse to the VM instance that you need to recover.

2.Select the respective Hyper-V host and expand that node.

3.Click All Protected Hyper-V Data, and then, in the Recovery Points pane, select the VM that you want to recover, as shown in the following image.

4.Click any date and time in the calendar to see available recovery points. Dates that show as bold have active recovery points. To minimize data loss, it is important to choose to recover from the latest possible recovery point.

5.Click Recover in the Actions pane to launch the Recovery Wizard.

6.In the Recovery Wizard, on the Select Recovery Type page, select Recover To Original Instance.

7.On the Specify Recovery Options page, leave the Network Bandwidth Usage Throttling and SAN Recovery selections without any modifications.

8. On the Summary page, review your settings, and then click Recover.

9. After the recovery completes, click Close to close the Recovery Wizard.

10. Start the VM that you just recovered.

11. After you recover the VM, you must synchronize it as follows (the protection status of this VM will show as Replica Inconsistent until it is synchronized):

a. In the DPM administrator console, open the Protection workspace.

b. Locate and then right-click the recovered VM. Click Perform Consistency Check.

c. In the Microsoft System Center 2012 R2 Data Protection Manager dialog box, click Yes to perform the consistency check.

Source of Information : Microsoft System Center

Monday, October 30, 2017

Recovering Hyper-V data - How to restore a VM

In a private cloud deployment, it is recommended that you deploy all VMs with a golden image (a single parent VHD). Leveraging the same parent VHD and creating differencing disks for the VMs saves disk space. It is recommended that you keep the parent VHD on a high performant storage (for example, SSD) because most read operations will come from this VHD. DPM supports restoring the VM to the original location with or without a parent disk, but there are more steps involved with the latter option. The following steps show an example Alternate Location Recovery where you use DPM to restore a VM that has only a single parent disk and recover it to an alternate location. Start by getting the information from Virtual Machine Manager on which DPM server protects the VM that needs to be recovered to the original location. (This is DPMServer01 in this example.)

1. Delete the corrupt VM:
Stop-VM -ComputerName HyperVHostName -Name VMName 
Remove-VM -ComputerName HyperVHostName -Name VMName

In the preceding command, HyperVHostName is the host on which the corrupt VM is located.

2. Create a symbolic link on the target server:
Enter-PSSession -ComputerName  
cd c:\ cmd /c "mklink /d link
exit

In the preceding command, RecoveryHost is the host on which the VM needs to be recovered and SharedLocation is the storage location for the recovered VM.

3. Connect to the DPM server, get the protection group on the DPM server named DPMServer01, and store the results in the $Pg variable:
$Pg = Get-DPMProtectionGroup -DPMServerName "DPMServer01" | where {$_.Name –eq "PGName"}

4. Get the list of protected and unprotected data in the protection group and store the data source object:
$Ds = Get-DPMDatasource -ProtectionGroup $Pg | where {$_.Computer -eq }

5. Specify the recovery points for the given data source:
$Rps = Get-DPMRecoveryPoint -Datasource $Ds

6. Specify a particular recovery point:
$Rp = $Rps[$Rps.Length – 1]

In the preceding command, - 1 indicates the latest recover point; - 2 would be the recovery point before that, and so on.

7. Recover the item to the alternate location (Hyper-V host):
$Rpo = New-DPMRecoveryOption -HyperVDatasource -TargetServer HyperVHostName -RecoveryLocation AlternateHyperVServer -RecoveryType Recover -TargetLocation  
Recover-RecoverableItem -RecoverableItem $Rp -RecoveryOption $Rpo


8. Connect to the host where the VM has been recovered and perform the following steps:
a. Perform storage migration
Move-VMStorage -ComputerName HyperVHostName -VMName VMName -DestinationStoragePath

b. Re-parent the recovered VM to its original parent:
Get-VMHardDiskDrive VMName | Get-VHD | where {$_.parentPath -ne $null} | Set-VHD -ParentPath

c. Delete the local parent VHD that was just recovered.

d. Delete the symbolic link (“c:\link”) by opening Windows PowerShell session as an elevated user.

e. Configure the recovered VM as a highly available source:
Get-VM –Name VMName | Select VMId, ConfigurationLocation $res = Get-ClusterResource -Name "VMClusterResourceName" -Cluster ComputeClusterName Set-ClusterParameter -InputObject $res -Name VMId -Value -Cluster ComputeClusterName

Source of Information : Microsoft System Center

Sunday, October 29, 2017

Recovering Hyper-V data - How to restore a file from a VM

Restoring a file from a VM is the marquee feature of DPM. Based on customer conversations, it was found that most recoveries happen for files that were backed up within the last 7 to 14 days and most tenant requests are for files that were deleted inadvertently. The advantage of DPM is that the entire VM doesn’t need to be recovered to get a single file. Instead, the VHD (which has the file) is mounted on the DPM server and the file is recovered to an alternate location.

Complete the following steps to recover a file. These steps provide the recovered file when the VMs don’t use the single parent disk.

1.Go to the Recovery workspace in the DPM console.

2.Select the VM from which you would like to recover the file.

3.Pick the date and time for the recovery.

4.Select the VHD and browse to the file you want to recover (e.g., win.ini).

5. Right-click the selected file and select Recover. The Recovery Wizard opens.

6. On the Review Recovery Selection page, review the recovery item, date, time, media type, and then click Next.

7. On the Select Recovery Type page, specify the type as Copy To A Network Folder.

8. On the Specify Destination page, select the destination (volume or share) and it automatically populates the available space on the destination.

9. On the Specify Recovery Options page, configure specific options (e.g., security settings, network bandwidth usage throttling) for the recovery.

10. On the Summary page, review all the information, and then click Recover. If recovery succeeds, the recovery status shows as Successful on the Recovery Status page.

Source of Information : Microsoft System Center

Saturday, October 28, 2017

Continued protection with VM migration

VM migration refers to the process in which a running VM moves to another physical machine, keeping memory, network connectivity, and storage intact, which implies the application continues to run as-is without any disruption. This can happen due to a host server crash or due to re-balancing the resources in a cluster. So the expectation is that backups should run uninterrupted even if the VM moves to another node in the same cluster or even a different cluster. The same DPM server continues to protect the VM even after live migration. If the VM moves to a different cluster, DPM integration with Virtual Machine Manager helps discover the VM on a node in the new cluster.


Protecting replica VMs
The first question that comes to customers’ minds is whether they should protect the replica VMs. In customer conversations, three scenarios are found to be useful when protecting replica VMs:

 Reduce the impact of backup on the production workloads In today’s world, workloads need to run 24 hours a day, 7 days a week with high performance. Workloads run on differencing disks during the backup operation and do impact the system.

Limited network bandwidth between the branch office and head officeNetwork bandwidth is expensive, and it is redundant to send data to the head officetwice, once for disaster recovery and then for backup. A more efficient way is tosupport backup from a replica site so that customers can manage the backupinfrastructure from a single site.

Enterprise to hoster scenario Most customers don’t want to build anotherdatacenter for disaster recovery and prefer to leverage a hosting service provider orpublic cloud. Hosting service providers offer SLAs around backing up customers’ VMson a regular frequency (for example, daily), and this can be easily achieved usingreplica VM backup.

There is some limitation with these scenarios: you can only get crash-consistent backups. However, most customers are comfortable with this. Remember, crash-consistency doesn’t mean inconsistency. It’s equivalent to the state when the power plug is pulled. Applications know how to recover from this state.


Protecting servers in workgroups and untrusted domains
DPM supports protecting Hyper-V VMs on the servers that use local user account (NTLM authentication) or that use certificates. For Hyper-V clusters, only certificate authentication is supported, not the NTLM certification. Even protection of a primary DPM server to a secondary DPM (in an untrusted domain) is supported through certificate authentication.

Source of Information : Microsoft System Center

Friday, October 27, 2017

Protecting Hyper-V VMs

This section covers what can be protected, different deployment topologies, and performance and scale numbers. Hot backups of Microsoft workloads (for example, SQL Server, Exchange Server, SharePoint Server, and file servers) and Linux workloads is supported. Note that you get app consistent backups for the VMs running Microsoft workloads while you get file-consistent snapshots for the VMs running Linux workloads due to no Volume Shadow Copy Service (VSS) support in the guest.

DPM can be used to protect VMs hosted on the following:
 Standalone Hyper-V hosts that use local or direct-attached storage. Note that this option does not provide continuous availability and is not recommended for production deployments.

 Hyper-V cluster with storage on Server Message Block (SMB) shares backed by an SOFS cluster. This deployment type is referred to as “Hyper-V over SOFS.”

 Hyper-V cluster with the virtual hard disks stored on Clustered Shared Volumes (CSV). This deployment type is referred to as “Hyper-V over CSV.”


Protecting Hyper-V over SOFS
Hyper-V over SOFS configuration (with Storage Spaces) enables cost-effective, highly available, scalable, and flexible storage solutions for business-critical virtual deployments. It leverages industry-standard storage and allows customers to use Windows Server for highly available storage that can cost-effectively grow with demand. In this configuration, compute and storage are decoupled, and you can independently scale one without the need to scale the other. This configuration provides the lowest acquisition and operations cost. It allows highly available VMs, continuously available file servers, and fault-tolerant storage. The only challenge with this configuration is hardware setup and software installation unless you decide to go with the Cloud Platform System option.

Here are some considerations when using Hyper-V over SOFS and what they mean from a backup perspective:

 The file server must have Windows Server 2012 R2 with the new SMB 3.0 protocol. In order to get scalable backups with DPM, you cannot use non-Microsoft file servers that implement the SMB 3.0 protocol (because the DPM agent doesn’t work with these file servers).

 You must have separate failover clusters for Hyper-V and for the file server. DPM agents should be installed on the Hyper-V cluster nodes and on all the storage nodes (since the storage server is also clustered). You’ll need full-share and folder-level permissions for the local $ account of the file server on the SMB share.

Now consider the failure scenarios. What if the compute node goes down? There is no impact to the protected VMs on that node since the tracking is on the storage node. If there is a DPM VM on that node, all running jobs fail and are re-tried automatically.

What if the storage node goes down? All VMs that are touched by this storage node (since the last backup) go into CC mode since the tracking is on the storage node. In Cloud Platform System, where one rack can host up to 2,000 VMs on a four-node SOFS cluster, roughly 500 VMs go into CC mode when one storage node goes down.

How do the scale numbers look? In a scale test conducted by the DPM Product Group, continuous daily backups for three weeks (using virtualized DPM servers) were taken where the workload running inside each of the VMs was spread across multiple I/O profiles (SQL OLTP, Exchange, File Server, Video Streaming, and SQL Decision Support System). The guest operating system used for the protected VMs was Windows Server 2012 R2.

Scale testing with each DPM server protecting between 50 to 250 VMs was performed. DPM VMs were deployed in scale-out configuration to protect VMs from the same Hyper-V cluster nodes. Results were pivoted around the following criteria:

 Backup success rate per day This signifies the percentage of VMs having successful backups in a single day.

 Overall backup success rate This signifies overall percentage of successful backups across all VMs for a three-week duration.

More than 98 percent success was achieved for both the metrics. It also implies that there were more than 20,000 jobs that ran successfully during this three-week duration. The few errors encountered were due to known auto-recoverable failures, such as “Out of storage space” and “Retry-able VSS errors.”


Protecting Hyper-V over CSV
Hyper-V over CSV (backed by SAN) is the most predominant deployment where VMs are hosted on a Hyper-V cluster with CSV storage. There is no limit to the number of disks a Hyper-V cluster can be configured to use, which allows much flexibility in designing the storage architecture of Hyper-V host clusters. For backing up the VMs, the DPM agent is installed on each cluster node, and you get reliable backups at scale with the latest version of DPM 2012 R2. There are no more host-level volume snapshots; it calls guest-level VSS to get application-consistent backups. DPM supports express full backups and parallel backups.

Now, consider the failure scenarios. What if the compute node goes down? All protected VMs on that host go into CC mode since the filter tracking is on that node. If there is a DPM VM on that host, all running jobs fail and are re-tried automatically. There is no impact on the jobs that have succeeded, and the jobs in queue continue to be in the queue even after the DPM VM moves to the new node in the cluster.

Source of Information : Microsoft System Center