We just updated our Dev environment (thank goodness it was only Dev) from:
Workflow:18.104.22.168 - 22.214.171.124
Forms: 126.96.36.199 - 188.8.131.52
And noticed some very strange behaviour, post upgrade.
We were getting 503 errors while trying to access any SharePoint resources, and the following was appearing in the event logs on the web servers:
SQL database login for 'DevConfigDB' on instance 'DevSQLServer' failed. Additional error information from SQL Server is included below.
Login failed for user 'DOMAIN\SERVERNAME$'.
The default access account for the Configuration DB had changed from the farm account to the machine account!
I had to delete the timer job definition: (SPAdminAppPoolCredentialDeploymentJobDefinition job) and reapply the farm credentials to 'Farm Account' within CA to resolve this issue.
Has anyone else noticed this or similar behaviour?