Handling Farm Password Changes
Many installations require all users to change passwords periodically. If all the nodes in a farm share the same service account and the service account password needs to be changed, you must carry out the following steps on all machines that have been added as nodes to the farm:
Log out of the service account.
Log back into the service account using the new password.
Run the following cmdlets from the PowerShell prompt of Microsoft AppFabric Server:
FarmPassword = ConvertTo-SecureString -String MyFarmsPassword -AsPlainText -Force $AccountPassword = ConvertTo-SecureString -String NewPassword -AsPlainText -Force Stop-SBHost -Verbose Update-SBHost -RunAsPassword $AccountPassword -CertificateGenerationKey $FarmPassword –Verbose Start-SBHost -Verbose
You can now add nodes to the farm or remove nodes from it again.