An Issue with changing ProxyGroup for a ServiceApplication in SharePoint

We had an issue with multiple proxy groups and UPA , MMS configurations.

My suggestion is, Do not use Central Administration UI for creating or changing proxy group of Service Applications from UI.

Instead use Powershell scripts.

And don’t forget to set manually “SPServiceApplication.ServiceApplicationProxyGroup” property for each ServiceApplication if you move it rather than default proxy group.

If you do it from UI this property always be “NULL” in configuration database and persisted object of ServiceApplication is not updated. SO when you or SharePoint reach to ProxyGroup of a Service Application, if this property is NULL it returns the Default proxy group even the Service Application is on another proxy group.

Well if you already move it from UI, you should update the ServiceApplications as below where they are not in default proxy group.

Example:
#Lets assume we have 2 proxy group  “default” and “myProxyGroup”
#Get the related Service Application where it is present in “myProxyGroup”
#You should do it for all ServiceApplications if they are not in default proxy group.

$app = Get-SPServiceApplication -Identity <GUID>

$ProxyGroups = Get-SPServiceApplicationProxyGroup
$myProxyGroup = $ProxyGroups[1]   # -> this is my second proxy group.

#Set it manually
$app.ServiceApplicationProxyGroup = $myProxyGroup
$app.Update()

Resources:
https://docs.microsoft.com/en-us/powershell/module/sharepoint-server/get-spserviceapplicationproxygroup?view=sharepoint-ps

https://docs.microsoft.com/en-us/sharepoint/administration/add-or-remove-a-service-application-connection-to-a-web-application

https://docs.microsoft.com/en-us/powershell/module/sharepoint-server/add-spserviceapplicationproxygroupmember?view=sharepoint-ps

Creating New Service Application Proxy Groups and Associating Services and Sites