What is a Windows Server migration and why would an administrator want to do one? A migration is when you move one role or feature at a time from one windows server to another. For example moving files or users between two windows servers.
Migrations are commonly done when servers are being decommissioned, running out space or simply not performing up to a business’s needs. Microsoft is known for providing easy to use administration tools and they have done so for the migration process with a tool called Storage Migration Service.
Storage Migration Service migrates files and server configuration from one windows server to another. If you need to migrate applications between two servers a 3rd party application may be necessary. Two popular ones to check out are EaseUS Todo PCTrans and Zinstall WinServ.
Storage Migration Service Overview
Storage Migration Service is a graphical tool that inventories data on one server and transfers it to another server. The original server can be Linux or Windows based. The new server can be either a Windows Server or an Azure virtual machine.
It performs migrations relatively rapidly and allows administrators the ability to manage multiple migrations from a single user interface. It can even set up the new server with the identity of the source server. This means your users and apps will not have to change anything to access the data after the migration process. The migration is seamless.
Note that Storage Migration Service cannot automate cut over on domain controllers. It can only transfer files between them.
Source and Destination Server Requirements
The source server can be Linux or Windows based. The requirements for it are very few, Windows Server 2003 or newer. It will also need internet access and a migration account that is an administrator.
The destination server should be running Windows Server 2012 R2 or newer. Expect older versions of Windows Server to have a slower migration than newer versions. The destination server should have at least two cores and 2 GB of memory.
If your transfer is happening slower than you would like, try increasing the memory and processing power of the destination server.
When completing a migration, you will also need an orchestrator server running Windows Server 2019. If you are only migrating one server at a time, and if your destination server is running Windows Server 2019 you can use it as your orchestrator server.
You will need an administrator account on all servers. The orchestrator server should have File and Print Sharing firewall rule enabled inbound.
The source and destination servers need to have the following firewall rules enabled inbound:
- File and Print Sharing
- Netlogon Service
- Windows Management Instrumentation
- Windows Management Instrumentation
There are a few additional considerations if the computers are in an Active Directory domain. All the servers should belong to the same forest. If you want to cut over to the destination server after migration and maintain the same fully qualified domain name, then the destination and source servers must be in the same domain.
Install Windows Admin Center on your server on the same domain or forest as the source computers. Open Windows Admin Center and connect to the orchestrator server.
Install Storage Migration Server on the orchestrator server. Do this by going to Server Manager -> Storage Migration Service and selecting Install (in Windows Admin Center.)
Install Storage Migration Service proxy on the destination server. This will significantly speed up the migration. Do this by going to Server Manager->Roles and features->Features->Storage Migration Service Proxy and select Install.
The migration process will be completed in three steps: Inventory Servers, Transfer Data and Cut Over. The cut over step is optional. If you choose to do the cut over step, the source servers will enter a maintenance state and be unavailable to users and apps. No files will be deleted. You can decommission the source servers whenever convenient.
Step 1: Inventory Servers
- In Windows Admin Center, select New Job. Enter the name of the job and select what type of server you are migrating from (Windows or Linux.)
- Enter credentials for the source server or servers. They must be admin credentials.
- Click Add a Device and type the source server name. Repeat for multiple servers.
- Click Start scan.
- Once the scan is complete, click on each server to review the inventory. You will see warnings for files that may integer with Windows operations. You will need to skip these files during the transfer step. For a full list of files that will be skipped click here.
- Click Next to move on to transferring data.
Step 2: Transfer Data
- Go to the Transfer data -> Enter credentials page and enter the admin credentials for the destination server or servers.
- Go to the Add a destination device and mappings page. You will see the source server or servers listed there. Type in the name of the destination and click Scan device. You can also choose Create a new Azure VM. The wizard will automatically size your VM.
- Map source volumes to destination volumes. If you don’t want to transfer a particular share uncheck the Include checkbox.
- Repeat for each source / destination server pair.
- Go to the Adjust transfer settings page to select user and group options. You will have three options.
- Rename accounts with the same name. This is the default option and will rename any users or groups whose names match between the source and destination server. Do not use if you are transferring files between domain servers.
- Reuse accounts with the same name. This option will map, rather than create, users and user groups that match between the source and destination servers.Do not use if you are transferring files between domain servers.
- Don’t transfer users and groups. This option ignores users and groups during the transfer process and is what you want to use when transferring files between domain servers.
- Click Validate
- Click Start transfer
- You now have two options to choose from.
- Go to the next step - cut over to the destination server.
- Complete the migration
Step 3: Cutting Over to Destination Server (optional)
- You should still be in Windows Admin Center and at the Storage Migration Service. Select your job.
- Go to the Cut over to new servers page and enter your admin credentials.
- Go to the Configure cutover page and select the network adapter that should take over for the source. This will move the IP address. The source server will get a new IP address, either DHCP or static.
- Specify the new IP address for the source to use after the cutover. If specifying a static IP, the new subnet must be the same as the old or the cutover will fail.
- Specify a new name for the source server.
- Click Next on the Adjust cutover settings page and Validate on the Validate source and destination device page.
- Click Start cutover when you are ready to perform the cutover. Users may experience an outage during the cutover process. The duration of that outage depends on the server’s restart time and the Active Directory replication times.
Known Issues with Storage Migration Service
There are some known issues with Storage Migration Service. Log files are created during the process that can help you troubleshoot any issues you may run into.
The orchestrator server will house event logs for the orchestrator service and proxy service. The destination servers will only house the proxy service log files.
These logs can be found under Application and Service Logs\ Microsoft\ Windows\ StorageMigrationService and StorageMigrationService-Proxy.