Customize migration plan for Windows IIS services

Review the migration plan file that was populated during the creation of the migration. You can customize it before proceeding to execute the migration. The details of your migration plan are used to extract the workload container artifacts from the source VM.

This section describes the contents of the migration plan and the kinds of customizations that you might consider before you execute the migration, and generate deployment artifacts.

Before you begin

This document assumes that you've already created a migration plan and have the resulting migration plan file.

Migration plan structure

Following is the full migration plan structure. The next sections discuss this structure, explain what each part is, and how to modify it.

  globalSettings 
 : 
  
 globalIis 
 : 
  
 enablegmsa 
 : 
  
 string 
  
 apppools 
 : 
  
 - 
  
 enable32bitapponwin64 
 : 
  
 bool 
  
 identitytype 
 : 
  
 string 
  
 managedruntimeversion 
 : 
  
 string 
  
 name 
 : 
  
 string 
  
 connectionStrings 
 : 
  
 add 
 : 
  
 - 
  
 connectionstring 
 : 
  
 string 
  
 name 
 : 
  
 string 
  
 providername 
 : 
  
 string 
  
 security 
 : 
  
 authentication 
 : 
  
 windowsAuthentication 
 : 
  
 enabled 
 : 
  
 bool 
  
 providers 
 : 
  
 - 
  
 value 
 : 
  
 string 
  
 authorization 
 : 
  
 add 
 : 
  
 - 
  
 access_type 
 : 
  
 string 
  
 roles 
 : 
  
 string 
  
 users 
 : 
  
 string 
  
 verbs 
 : 
  
 string 
  
 remove 
 : 
  
 - 
  
 roles 
 : 
  
 string 
  
 users 
 : 
  
 string 
  
 verbs 
 : 
  
 string 
  
 image 
 : 
  
 extraFeatures 
 : 
  
 - 
  
 string 
  
 target 
 : 
  
 baseVersion 
 : 
  
 string 
  
 requirements 
 : 
  
 - 
  
 string 
  
 warnings 
 : 
  
 - 
  
 string 
  
 msvcRuntimes 
 : 
  
 - 
  
 string 
  
 pathEnvVarAdditionalEntries 
 : 
  
 - 
  
 string 
 images 
 : 
  
 - 
  
 name 
 : 
  
 string 
  
 probes 
 : 
  
 enabled 
 : 
  
 bool 
  
 livenessProbe 
 : 
  
 probehandler 
 : 
  
 exec 
 : 
  
 command 
 : 
  
 - 
  
 string 
  
 - 
  
 string 
  
 initialdelayseconds 
 : 
  
 int 
  
 timeoutseconds 
 : 
  
 int 
  
 periodseconds 
 : 
  
 int 
  
 successthreshold 
 : 
  
 int 
  
 failurethreshold 
 : 
  
 int 
  
 terminationgraceperiodseconds 
 : 
  
 optional 
 [ 
 int 
 ] 
  
 readinessProbe 
 : 
  
 probehandler 
 : 
  
 exec 
 : 
  
 command 
 : 
  
 - 
  
 string 
  
 - 
  
 string 
  
 initialdelayseconds 
 : 
  
 int 
  
 timeoutseconds 
 : 
  
 int 
  
 periodseconds 
 : 
  
 int 
  
 successthreshold 
 : 
  
 int 
  
 failurethreshold 
 : 
  
 int 
  
 terminationgraceperiodseconds 
 : 
  
 optional 
 [ 
 int 
 ] 
  
 useractions 
 : 
  
 files 
 : 
  
 - 
  
 source 
 : 
  
 string 
  
 target 
 : 
  
 string 
  
 registry 
 : 
  
 currentcontrolset 
 : 
  
 - 
  
 path 
 : 
  
 string 
  
 software 
 : 
  
 - 
  
 path 
 : 
  
 string 
  
 workloads 
 : 
  
 sites 
 : 
  
 site 
 : 
  
 - 
  
 applications 
 : 
  
 - 
  
 applicationpool 
 : 
  
 string 
  
 path 
 : 
  
 string 
  
 virtualdirectories 
 : 
  
 - 
  
 path 
 : 
  
 string 
  
 physicalpath 
 : 
  
 string 
  
 bindings 
 : 
  
 - 
  
 port 
 : 
  
 int 
  
 protocol 
 : 
  
 string 
  
 sslflags 
 : 
  
 int 
  
 connectionstrings 
 : 
  
 - 
  
 connectionstring 
 : 
  
 string 
  
 name 
 : 
  
 string 
  
 providername 
 : 
  
 string 
  
 name 
 : 
  
 string 
  
 security 
 : 
  
 authentication 
 : 
  
 windowsAuthentication 
 : 
  
 enabled 
 : 
  
 bool 
  
 providers 
 : 
  
 - 
  
 value 
 : 
  
 string 
  
 authorization 
 : 
  
 add 
 : 
  
 - 
  
 access_type 
 : 
  
 string 
  
 roles 
 : 
  
 string 
  
 users 
 : 
  
 string 
  
 verbs 
 : 
  
 string 
  
 remove 
 : 
  
 - 
  
 roles 
 : 
  
 string 
  
 users 
 : 
  
 string 
  
 verbs 
 : 
  
 string 
  
 serverautostart 
 : 
  
 bool 
 version 
 : 
  
 string 
 

The globalSettings section

The globalSettings section describes basic requirements for pods running IIS sites from this VM. The discovery process searches for general configurations in the source VM, and uses them to populate this section. These configurations contain fields present in the specific image configurations as described in the following section, and affects all images at the same time.

The image section

The image section following globalSettings describes the list of Windows features to install on the pods. The discovery process populates this section with all Windows features which exist on the original VM, and can be installed on a Windows container.

The msvcRuntimes section

When migrating an application, it might have a dependency on a specific version or versions of the Microsoft Visual C++ Runtime (MSVCRT). Migrate to Containers automatically detects the runtimes installed on the source VM and included them in the migration plan.

You can modify the list of runtimes in the migration plan by adding or removing members of msvcRuntimes :

The complete list of possible values are: (The 2015 runtime also includes support for 2017, 2019, and 2022)

   
 msvcRuntimes 
 : 
  
 - 
  
 MSVC2012_x64 
  
 - 
  
 MSVC2013_x64 
  
 - 
  
 MSVC2015_x64 
  
 - 
  
 MSVC2012_x86 
  
 - 
  
 MSVC2013_x86 
  
 - 
  
 MSVC2015_x86 
 

The pathEnvVarAdditionalEntries section

Windows IIS applications might have non-default PATH environment variable entries, which are automatically detected on the source VM and included in the migration plan. You can modify the PATH environment variables by editing the members of pathEnvVarAdditionalEntries :

   
 pathEnvVarAdditionalEntries 
 : 
  
 - 
  
 "C:\\myDllsFolder" 
  
 - 
  
 "C:\\ProgramData\\SomeSoftware" 
 

Edit the image section

You might want to edit the image section in the following cases:

1. Some suggested features are not be required by the migrated sites. This happens if the source VM has usages other than hosting IIS sites.

2. You modified the IIS sections in the migration plan, and added configurations that depend on additional Windows features. (For example, Windows authentication depends on the Window authentication feature).

The target section

The target section specifies which base Windows image you're using (for example 1909). You should rarely need to edit this field.

The images section

Each subitem of the images section specifies a single output image.
In the artifacts zip, each such image has a separate subdirectory, with its own Dockerfile and deployment_spec.yaml (see Deploying the container image ).

The name field

The name field describes the image name. It affects the name of the image subdirectory and the deployment_spec.yaml file in the artifacts.

The probes field

The probes field describes the health probe configuration of the image. To learn more about kubelet probes, see Configure Liveness, Readiness and Startup Probes .

Edit IIS health probes

Health probes can monitor the downtime and ready status of your managed containers. Health probe monitoring can help reduce the downtime of migrated containers and provide better monitoring.

Unknown health states can create availability degradation, false-positive availability monitoring, and potential data loss. Without a health probe, kubelet can only assume the health of a container and might send traffic to a container instance that is not ready. If the instance is not ready, it can cause traffic loss. Kubelet might also not detect containers that are in a frozen state and doesn't restart them.

A health probe functions by running a small scripted statement when the container starts. The script checks for successful conditions, which are defined by the type of probe used, every period. The period is defined in the migration plan by a periodSeconds field. You can define these probes manually when you customize the migration plan.

There are three types of probes available to configure. All probes are probe v1 core defined in probe v1 core reference and share the same function as the corresponding fields of container v1 core .

• * Liveness probe:Liveness probes are used to know when to restart a container.

• Readiness probe:Readiness probes are used to know when a container is ready to start accepting traffic. To start sending traffic to a pod only when a probe succeeds, specify a readiness probe. A readiness probe might act similarly to a liveness probe. However, a readiness probe indicates that a pod starts without receiving any traffic and only start receiving traffic after the probe succeeds.

• Startup probe:The kubelet uses startup probes to know when a container application has started. If such a probe is configured, it disables liveness and readiness checks until it succeeds, making sure that those probes don't interfere with the application startup.

After discovery, the probe configuration is added to the migration plan. The probes can be used in their default configuration as shown in the following example. The default configuration uses exec command for the liveness and readiness probes. Both are using a PowerShell script called probe.ps1 that calls IIS command-line tool appcmd to check the status of the IIS sites.

The probes are disabled by default, to enable the probes, set the enabled flag to true .

 images 
 : 
 name 
 : 
  
 IMAGE_NAME 
  
 probes 
 : 
  
 enabled 
 : 
  
 false 
  
 livenessProbe 
 : 
  
 probehandler 
 : 
  
 exec 
 : 
  
 command 
 : 
  
 - 
  
 powershell.exe 
  
 - 
  
 C:\m4a\probe.ps1 
  
 initialdelayseconds 
 : 
  
 0 
  
 timeoutseconds 
 : 
  
 1 
  
 periodseconds 
 : 
  
 10 
  
 successthreshold 
 : 
  
 1 
  
 failurethreshold 
 : 
  
 3 
  
 terminationgraceperiodseconds 
 : 
  
 null 
  
 readinessProbe 
 : 
  
 probehandler 
 : 
  
 exec 
 : 
  
 command 
 : 
  
 - 
  
 powershell.exe 
  
 - 
  
 C:\m4a\probe.ps1 
  
 initialdelayseconds 
 : 
  
 0 
  
 timeoutseconds 
 : 
  
 1 
  
 periodseconds 
 : 
  
 10 
  
 successthreshold 
 : 
  
 1 
  
 failurethreshold 
 : 
  
 3 
  
 terminationgraceperiodseconds 
 : 
  
 null 

The windowsServices section

Windows containers created during a migration run and monitor a single Windows IIS service. However, some workloads might require running additional services (including a database, logging mechanism, proxy, and more) in order to function correctly.

To run additional services in the migrated container, add entries to the windowsServices section, and copy the necessary binaries in the useractions section .

 version: v1
globalSettings:
    target:
       …
    globalIIS:
    …
images:
  - name: migrated-image-zgwb2
    workloads:
    sites:
      site:
        - applications:
          ...
          bindings:
          - port: 80
            protocol: http
          name: Default Web Site
          …
    windowsServices:
    - MyService
    useractions:
      files:
        - source: C:\Program Files\MyService
          target: C:\Program Files\MyService
      registry:
        currentcontrolset:
          - key: services\MyService 

The useractions section

The useractions section specifies additional files and registry keys that you might want to migrate.

For example:

  
 useractions 
 : 
  
 files 
 : 
  
 - 
  
 source 
 : 
  
  DRIVE 
 
:\ FOLDER-OR-FILE-PATH 
  
 target 
 : 
  
  DRIVE 
 
:\ FOLDER-OR-FILE-PATH 
  
 - 
  
 source 
 : 
  
 C:\myfolder 
  
 target 
 : 
  
 C:\myfolder 
  
 - 
  
 source 
 : 
  
 D:\myfile 
  
 target 
 : 
  
 D:\myfile 
  
 - 
  
 source 
 : 
  
 D:\myfile 
  
 target 
 : 
  
 C:\myfile 
  
 ... 
  
 registry 
 : 
  
 currentcontrolset 
 : 
  
 - 
  
 path 
 : 
  
  KEY 
 
  
 ... 
  
 software 
 : 
  
 - 
  
 path 
 : 
  
  KEY 
 
  
 ... 

The paths specified for currentcontrolset and software are to keys in the HKEY_LOCAL_MACHINE\System\CurrentControlSet registry hive or in the HKEY_LOCAL_MACHINE\Software registry hive.

Edit the useractions section

By default the only files copied to the image are the virtual directories of sites in the specified image.
If your code or configurations import files from outside this directory, you should add them to the useractions section.
Also, any registry values that your code depends on should be added by editing the useractions registry section.

Settings related specifically to IIS

The IIS related settings are divided into settings related to specific sites, which are part of the image specification, and settings related to all sites, which are following the gloabalIis section.

The sites section

The sites section describes the sites that are migrated to a specific image. It's possible for several images to contain the same site.

If you want to use Cloud Load Balancing, Ingress, or Cloud Service Mesh to handle the SSL configuration , then you need to set protocol to http :

 sites 
 : 
  
 site 
 : 
  
 - 
  
 applications 
 : 
  
 - 
  
 path 
 : 
  
 / 
  
 virtualdirectories 
 : 
  
 - 
  
 path 
 : 
  
 / 
  
 physicalpath 
 : 
  
 '%SystemDrive%\inetpub\wwwroot' 
  
 bindings 
 : 
  
 - 
  
 port 
 : 
  
 8080 
  
  protocol 
 : 
  
 http 
  
 name 
 : 
  
 Default Web Site 

The apppools section

The apppools section describes the Application Pools created on the migrated pods.

The identitytype field specifies the IIS identity of an application pool as either ApplicationPoolIdentity (default), NetworkService , LocalSystem , or LocalService .

For more information, see Understanding identities in IIS and Application Pool Identities .

The following is an example migration plan containing identitytype :

 migrationPlan 
 : 
  
 applications 
 : 
  
 iis 
 : 
  
 applicationhost 
 : 
  
 apppools 
 : 
  
 - 
  
 name 
 : 
  
 DefaultAppPool 
  
 # Allowed values include: ApplicationPoolIdentity (default), NetworkService, LocalSystem, LocalService 
  
  identitytype="NetworkService" 
  
 - 
  
 managedruntimeversion 
 : 
  
 v4.0 
  
 name 
 : 
  
 .NET v4.5 Classic 
  
 - 
  
 managedruntimeversion 
 : 
  
 v4.0 
  
 name 
 : 
  
 .NET v4.5 

When you execute the migration plan to generate the container artifacts, Migrate to Containers automatically adds the necessary Dockerfile directives according to the identitytype field setting.

For example, if you set identitytype to NetworkService the directive is in the form:

 RUN c:\windows\system32\inetsrv\appcmd.exe set apppool \"DefaultAppPool\" \"/-processModel.identityType:NetworkService\"; 

Migrate to Containers automatically adds read ACL directives to the site's folders according to the target identitytype , and for the IUSR built-in user. This is automatically done for application file system items where the original application account was specified either by inheritance or explicitly.

For more information, see Set ACLs .

The enablegmsa field

The enablegmsa field is syntactic sugar in the migration plan. It's a shortcut for overwriting the identity field of the application pool.

The supported values for enablegmsa field are:

• auto (default): Convert the migrated container to use gMSA if Migrate to Containers determines that its current configuration is not allowed.
• all : Always convert the migrated container to use gMSA and ignore the setting of identitytype . In this case, identitytype is always interpreted as being set to NetworkService .

The following is an example migration plan containing enablegmsa :

 migrationPlan 
 : 
  
 applications 
 : 
  
 iis 
 : 
  
 # Allowed values include: auto (default), all 
  
  enablegmsa 
 : 
  
 auto|all 

To learn more, see Configure your app to use a gMSA .

Connection strings

Connection strings define a connection from the migrated container workload to a .NET Framework data provider.

Migrate to Containers supports connection strings at the site and global scope.

To add a connection string to a site, edit the site definition in the migration plan to set the connectionstrings property:

 sites 
 : 
  
 site 
 : 
  
  # Add the site connection strings here. 
  
 connectionstrings 
 : 
  
 - 
  
 name 
 : 
  
 connectionname1 
  
 providername 
 : 
  
 System.Data.SqlClient 
  
 connectionstring 
 : 
  
 Database=connectedDB1;Password=Welcome1;User=admin; 
  
 - 
  
 name 
 : 
  
 connectionname2 
  
 providername 
 : 
  
 System.Data.OleDb 
  
 connectionstring 
 : 
  
 Database=connectedDB2;Password=Welcome2;User=admin; 
  
 - 
  
 applications 
 : 
  
 - 
  
 path 
 : 
  
 / 
  
 virtualdirectories 
 : 
  
 ... 

To add a connection string to the global scope (making it accessible to all sites), edit the connection strings directly following globalIis :

 globalIis 
 : 
  
 enablegmsa 
 : 
  
 auto 
  
 connectionStrings 
 : 
  
 connectionstring 
 : 
  
 - 
  
 name 
 : 
  
 connectionname3 
  
 providername 
 : 
  
 System.Data.SqlClient 
  
 connectionstring 
 : 
  
 Database=connectedDB3;Password=Welcome3;User=admin; 
  
 applicationhost 
 : 
  
 ... 

Where:

• name specifies the connection name.
• providername optionally specifies the data provider type. Migrate to Containers only supports a value of System.Data.SqlClient . supports the .NET Framework data provider:
  • System.Data.SqlClient
  • System.Data.OleDb
  • System.Data.Odbc
  • System.Data.OracleClient
• connectionstring specifies the Connection Strings used to connect to the data provider.

Edit the connection strings sections

Migrate to Containers automatically copies connection strings detected in the migrated VM to the migration plan.

Some connection strings might not be detected and should be added by editing the migration plan as shown preceding. (For example, if the connection strings are in an encrypted section of the applicationhost.config file).

For guidance on determining which connection strings to add to your migration plan, see Retrieving Connection Strings at Run Time in the Microsoft documentation.

Connection string external dependencies

• Connection strings can contain dependencies, such as a reference to a file at or to a Windows user associated with the site. You can add custom user actions to the migration plan to copy an extra file in the file system. Manually edit the Dockerfile to add a Windows user.
• Connection strings can contain dependencies, such as a reference to an external data source. These dependencies must be migrated manually to ensure that the migrated container workload has access to the data source.

The security section

The security sections contain the authentication and authorization subsections.

• Windows authentication verifies Active Directory users.
• Windows authorization is the mechanism for specifying which users are allowed which types of access to an IIS website. The access types are the HTTP verbs (POST, GET, PUT, PATCH, DELETE).

Similar to connection strings, to set authorization or authentication for all sites, edit globalIis as in the following example. To set authorization or authentication for a specific site, edit the site element.

 globalIis 
 : 
  
 security 
 : 
  
 authentication 
 : 
  
  windowsAuthentication 
 : 
  
 providers 
 : 
  
 - 
  
 NTLM 
  
 authorization 
 : 
  
 - 
  
 add 
 : 
  
 user:John 
  
 access 
 : 
  
 role 
 : 
  
  
 - 
  
 remove 
 : 
  
 user:Jane 
  
 access 
 : 
  
 GET 
  
 role 
 : 
  
  
  
 ... 

Where:

• providers specifies the provider of your security protocols.
• user species the username.
• access species the permissions of the user. The access types are the HTTP verbs (POST, GET, PUT, PATCH, DELETE).
• role species a specific permission role.

What's next

• Learn how to execute the migration .