Setting up a Windows Host ¶

This document discusses the setup that is required before Ansible can communicate with a Microsoft Windows host.

Topics

Setting up a Windows Host
- Host Requirements
  - Upgrading PowerShell and .NET Framework
  - WinRM Memory Hotfix
- WinRM Setup

Host Requirements ¶

For Ansible to communicate to a Windows host and use Windows modules, the Windows host must meet the following requirements:

Ansible’s supported Windows versions generally match those under current and extended support from Microsoft. Supported desktop OSs include Windows 7, 8.1, and 10, and supported server OSs are Windows Server 2008, 2008 R2, 2012, 2012 R2, and 2016.
Ansible requires PowerShell 3.0 or newer and at least .NET 4.0 to be installed on the Windows host.
A WinRM listener should be created and activated. More details for this can be found below.

Note

While these are the base requirements for Ansible connectivity, some Ansible modules have additional requirements, such as a newer OS or PowerShell version. Please consult the module’s documentation page to determine whether a host meets those requirements.

Upgrading PowerShell and .NET Framework ¶

Ansible requires PowerShell version 3.0 and .NET Framework 4.0 or newer to function on older operating systems like Server 2008 and Windows 7. The base image does not meet this requirement. You can use the Upgrade-PowerShell.ps1 script to update these.

This is an example of how to run this script from PowerShell:

$url = "https://raw.githubusercontent.com/jborean93/ansible-windows/master/scripts/Upgrade-PowerShell.ps1"
$file = "$env:temp\Upgrade-PowerShell.ps1"
$username = "Administrator"
$password = "Password"

(New-Object -TypeName System.Net.WebClient).DownloadFile($url, $file)
Set-ExecutionPolicy -ExecutionPolicy Unrestricted -Force

# version can be 3.0, 4.0 or 5.1
&$file -Version 5.1 -Username $username -Password $password -Verbose

Once completed, you will need to remove auto logon and set the execution policy back to the default of Restricted. You can do this with the following PowerShell commands:

# this isn't needed but is a good security practice to complete
Set-ExecutionPolicy -ExecutionPolicy Restricted -Force

$reg_winlogon_path = "HKLM:\Software\Microsoft\Windows NT\CurrentVersion\Winlogon"
Set-ItemProperty -Path $reg_winlogon_path -Name AutoAdminLogon -Value 0
Remove-ItemProperty -Path $reg_winlogon_path -Name DefaultUserName -ErrorAction SilentlyContinue
Remove-ItemProperty -Path $reg_winlogon_path -Name DefaultPassword -ErrorAction SilentlyContinue

The script works by checking to see what programs need to be installed (such as .NET Framework 4.5.2) and what PowerShell version is required. If a reboot is required and the username and password parameters are set, the script will automatically reboot and logon when it comes back up from the reboot. The script will continue until no more actions are required and the PowerShell version matches the target version. If the username and password parameters are not set, the script will prompt the user to manually reboot and logon when required. When the user is next logged in, the script will continue where it left off and the process continues until no more actions are required.

Note

If running on Server 2008, then SP2 must be installed. If running on Server 2008 R2 or Windows 7, then SP1 must be installed.

Note

Windows Server 2008 can only install PowerShell 3.0; specifying a newer version will result in the script failing.

Note

The username and password parameters are stored in plain text in the registry. Make sure the cleanup commands are run after the script finishes to ensure no credentials are still stored on the host.

WinRM Memory Hotfix ¶

When running on PowerShell v3.0, there is a bug with the WinRM service that limits the amount of memory available to WinRM. Without this hotfix installed, Ansible will fail to execute certain commands on the Windows host. These hotfixes should installed as part of the system bootstapping or imaging process. The script Install-WMF3Hotfix.ps1 can be used to install the hotfix on affected hosts.

The following PowerShell command will install the hotfix:

$url = "https://raw.githubusercontent.com/jborean93/ansible-windows/master/scripts/Install-WMF3Hotfix.ps1"
$file = "$env:temp\Install-WMF3Hotfix.ps1"

(New-Object -TypeName System.Net.WebClient).DownloadFile($url, $file)
powershell.exe -ExecutionPolicy ByPass -File $file -Verbose

WinRM Setup ¶

Once Powershell has been upgraded to at least version 3.0, the final step is for the WinRM service to be configured so that Ansible can connect to it. There are two main components of the WinRM service that governs how Ansible can interface with the Windows host: the listener and the service configuration settings.

Details about each component can be read below, but the script ConfigureRemotingForAnsible.ps1 can be used to set up the basics. This script sets up both HTTP and HTTPS listeners with a self-signed certificate and enables the Basic authentication option on the service.

To use this script, run the following in PowerShell:

$url = "https://raw.githubusercontent.com/ansible/ansible/devel/examples/scripts/ConfigureRemotingForAnsible.ps1"
$file = "$env:temp\ConfigureRemotingForAnsible.ps1"

(New-Object -TypeName System.Net.WebClient).DownloadFile($url, $file)

powershell.exe -ExecutionPolicy ByPass -File $file

There are different switches and parameters (like -EnableCredSSP and -ForceNewSSLCert) that can be set alongside this script. The documentation for these options are located at the top of the script itself.

Note

The ConfigureRemotingForAnsible.ps1 script is intended for training and development purposes only and should not be used in a production environment, since it enables settings (like Basic authentication) that can be inherently insecure.

WinRM Listener ¶

The WinRM services listens for requests on one or more ports. Each of these ports must have a listener created and configured.

To view the current listeners that are running on the WinRM service, run the following command:

winrm enumerate winrm/config/Listener

This will output something like the following:

Listener
    Address = *
    Transport = HTTP
    Port = 5985
    Hostname
    Enabled = true
    URLPrefix = wsman
    CertificateThumbprint
    ListeningOn = 10.0.2.15, 127.0.0.1, 192.168.56.155, ::1, fe80::5efe:10.0.2.15%6, fe80::5efe:192.168.56.155%8, fe80::
ffff:ffff:fffe%2, fe80::203d:7d97:c2ed:ec78%3, fe80::e8ea:d765:2c69:7756%7

Listener
    Address = *
    Transport = HTTPS
    Port = 5986
    Hostname = SERVER2016
    Enabled = true
    URLPrefix = wsman
    CertificateThumbprint = E6CDAA82EEAF2ECE8546E05DB7F3E01AA47D76CE
    ListeningOn = 10.0.2.15, 127.0.0.1, 192.168.56.155, ::1, fe80::5efe:10.0.2.15%6, fe80::5efe:192.168.56.155%8, fe80::
ffff:ffff:fffe%2, fe80::203d:7d97:c2ed:ec78%3, fe80::e8ea:d765:2c69:7756%7

In the example above there are two listeners activated; one is listening on port 5985 over HTTP and the other is listening on port 5986 over HTTPS. Some of the key options that are useful to understand are:

Transport: Whether the listener is run over HTTP or HTTPS, it is recommended to use a listener over HTTPS as the data is encrypted without any further changes required.
Port: The port the listener runs on, by default it is 5985 for HTTP and 5986 for HTTPS. This port can be changed to whatever is required and corresponds to the host var ansible_port.
URLPrefix: The URL prefix to listen on, by default it is wsman. If this is changed, the host var ansible_winrm_path must be set to the same value.
CertificateThumbprint: If running over an HTTPS listener, this is the thumbprint of the certificate in the Windows Certificate Store that is used in the connection. To get the details of the certificate itself, run this command with the relevant certificate thumbprint in PowerShell:
```
$thumbprint = "E6CDAA82EEAF2ECE8546E05DB7F3E01AA47D76CE"
Get-ChildItem -Path cert:\LocalMachine\My -Recurse | Where-Object { $_.Thumbprint -eq $thumbprint } | Select-Object *
```

Setup WinRM Listener ¶

There are three ways to set up a WinRM listener:

Using winrm quickconfig for HTTP or winrm quickconfig -transport:https for HTTPS. This is the easiest option to use when running outside of a domain environment and a simple listener is required. Unlike the other options, this process also has the added benefit of opening up the Firewall for the ports required and starts the WinRM service.
Using Group Policy Objects. This is the best way to create a listener when the host is a member of a domain because the configuration is done automatically without any user input. For more information on group policy objects, see the Group Policy Objects documentation.

Using PowerShell to create the listener with a specific configuration. This can be done by running the following PowerShell commands:

$selector_set = @{
    Address = "*"
    Transport = "HTTPS"
}
$value_set = @{
    CertificateThumbprint = "E6CDAA82EEAF2ECE8546E05DB7F3E01AA47D76CE"
}

New-WSManInstance -ResourceURI "winrm/config/Listener" -SelectorSet $selector_set -ValueSet $value_set

To see the other options with this PowerShell cmdlet, see New-WSManInstance.

Note

When creating an HTTPS listener, an existing certificate needs to be created and stored in the LocalMachine\My certificate store. Without a certificate being present in this store, most commands will fail.

Delete WinRM Listener ¶

To remove a WinRM listener:

# remove all listeners
Remove-Item -Path WSMan:\localhost\Listener\* -Recurse -Force

# only remove listeners that are run over HTTPS
Get-ChildItem -Path WSMan:\localhost\Listener | Where-Object { $_.Keys -contains "Transport=HTTPS" } | Remove-Item -Recurse -Force

Note

The Keys object is an array of strings, so it can contain different values. By default it contains a key for Transport= and Address= which correspond to the values from winrm enumerate winrm/config/Listeners.

WinRM Service Options ¶

There are a number of options that can be set to control the behavior of the WinRM service component, including authentication options and memory settings.

To get an output of the current service configuration options, run the following command:

winrm get winrm/config/Service
winrm get winrm/config/Winrs

This will output something like the following:

Service
    RootSDDL = O:NSG:BAD:P(A;;GA;;;BA)(A;;GR;;;IU)S:P(AU;FA;GA;;;WD)(AU;SA;GXGW;;;WD)
    MaxConcurrentOperations = 4294967295
    MaxConcurrentOperationsPerUser = 1500
    EnumerationTimeoutms = 240000
    MaxConnections = 300
    MaxPacketRetrievalTimeSeconds = 120
    AllowUnencrypted = false
    Auth
        Basic = true
        Kerberos = true
        Negotiate = true
        Certificate = true
        CredSSP = true
        CbtHardeningLevel = Relaxed
    DefaultPorts
        HTTP = 5985
        HTTPS = 5986
    IPv4Filter = *
    IPv6Filter = *
    EnableCompatibilityHttpListener = false
    EnableCompatibilityHttpsListener = false
    CertificateThumbprint
    AllowRemoteAccess = true

Winrs
    AllowRemoteShellAccess = true
    IdleTimeout = 7200000
    MaxConcurrentUsers = 2147483647
    MaxShellRunTime = 2147483647
    MaxProcessesPerShell = 2147483647
    MaxMemoryPerShellMB = 2147483647
    MaxShellsPerUser = 2147483647

While many of these options should rarely be changed, a few can easily impact the operations over WinRM and are useful to understand. Some of the important options are:

Service\AllowUnencrypted: This option defines whether WinRM will allow traffic that is run over HTTP without message encryption. Message level encryption is only supported when ansible_winrm_transport is ntlm, kerberos or credssp. By default this is false and should only be set to true when debugging WinRM messages.
Service\Auth\*: These flags define what authentication options are allowed with the WinRM service. By default, Negotiate (NTLM) and Kerberos are enabled.
Service\Auth\CbtHardeningLevel: Specifies whether channel binding tokens are not verified (None), verified but not required (Relaxed), or verified and required (Strict). CBT is only used when connecting with NTLM or Kerberos over HTTPS. The downstream libraries that Ansible currently uses only support passing the CBT with NTLM authentication. Using Kerberos with CbtHardeningLevel = Strict will result in a 404 error.
Service\CertificateThumbprint: This is the thumbprint of the certificate used to encrypt the TLS channel used with CredSSP authentication. By default this is empty; a self-signed certificate is generated when the WinRM service starts and is used in the TLS process.
Winrs\MaxShellRunTime: This is the maximum time, in milliseconds, that a remote command is allowed to execute.
Winrs\MaxMemoryPerShellMB: This is the maximum amount of memory allocated per shell, including the shell’s child processes.

To modify a setting under the Service key in PowerShell, the following command can be used:

# substitute {path} with the path to the option after winrm/config/Service
Set-Item -Path WSMan:\localhost\Service\{path} -Value "value here"

# for example, to change Service\Auth\CbtHardeningLevel run
Set-Item -Path WSMan:\localhost\Service\Auth\CbtHardeningLevel -Value Strict

To modify a setting under the Winrs key in PowerShell, the following command can be used:

# substitute {path} with the path to the option after winrm/config/Winrs
Set-Item -Path WSMan:\localhost\Shell\{path} -Value "value here"

# for example, to change Winrs\MaxShellRunTime run
Set-Item -Path WSMan:\localhost\Shell\MaxShellRunTime -Value 2147483647

Note

If running in a domain environment, some of these options are set by GPO and cannot be changed on the host itself. When a key has been configured with GPO, it contains the text [Source="GPO"] next to the value.

Common WinRM Issues ¶

Because WinRM has a wide range of configuration options, it can be difficult to setup and configure. Because of this complexity, issues that are shown by Ansible could in fact be issues with the host setup instead.

One easy way to determine whether a problem is a host issue is to run the following command from another Windows host to connect to the target Windows host:

# test out HTTP
winrs -r:http://server:5985/wsman -u:Username -p:Password ipconfig

# test out HTTPS (will fail if the cert is not verifiable)
winrs -r:http://server:5985/wsman -u:Username -p:Password -ssl ipconfig

# test out HTTPS, ignoring certificate verification
$username = "Username"
$password = ConvertTo-SecureString -String "Password" -AsPlainText -Force
$cred = New-Object -TypeName System.Management.Automation.PSCredential -ArgumentList $username, $password

$session_option = New-PSSessionOption -SkipCACheck -SkipCNCheck -SkipRevocationCheck
Invoke-Command -ComputerName server -UseSSL -ScriptBlock { ipconfig } -Credential $cred -SessionOption $session_option

If this fails, the issue is probably related to the WinRM setup. If it works, the issue may not be related to the WinRM setup; please continue reading for more troubleshooting suggestions.

HTTP 401/Credentials Rejected ¶

A HTTP 401 error indicates the authentication process failed during the initial connection. Some things to check for this are:

Verify that the credentials are correct and set properly in your inventory with ansible_user and ansible_password
Ensure that the user is a member of the local Administrators group or has been explicitly granted access (a connection test with the winrs command can be used to rule this out).
Make sure that the authentication option set by ansible_winrm_transport is enabled under Service\Auth\*
If running over HTTP and not HTTPS, use ntlm, kerberos or credssp with ansible_winrm_message_encryption: auto to enable message encryption. If using another authentication option or if the installed pywinrm version cannot be upgraded, the Service\AllowUnencrypted can be set to true but this is only recommended for troubleshooting
Ensure the downstream packages pywinrm, requests-ntlm, requests-kerberos, and/or requests-credssp are up to date using pip.
If using Kerberos authentication, ensure that Service\Auth\CbtHardeningLevel is not set to Strict.
When using Basic or Certificate authentication, make sure that the user is a local account and not a domain account. Domain accounts do not work with Basic and Certificate authentication.

HTTP 500 Error ¶

These indicate an error has occured with the WinRM service. Some things to check for include:

Verify that the number of current open shells has not exceeded either WinRsMaxShellsPerUser or any of the other Winrs quotas haven’t been exceeded.

Timeout Errors ¶

These usually indicate an error with the network connection where Ansible is unable to reach the host. Some things to check for include:

Make sure the firewall is not set to block the configured WinRM listener ports
Ensure that a WinRM listener is enabled on the port and path set by the host vars
Ensure that the winrm service is running on the Windows host and configured for automatic start

Connection Refused Errors ¶

These usually indicate an error when trying to communicate with the WinRM service on the host. Some things to check for:

Ensure that the WinRM service is up and running on the host. Use (Get-Service -Name winrm).Status to get the status of the service.
Check that the host firewall is allowing traffic over the WinRM port. By default this is 5985 for HTTP and 5986 for HTTPS.

Sometimes an installer may restart the WinRM or HTTP service and cause this error. The best way to deal with this is to use win_psexec from another Windows host.