Recently, during the VUM 5.5 U2 installation and configuration I have faced again an error when I tried to enable the VUM plugin:
There was an error connecting to VMware vSphere Update Manager. Database temporarily unavailable or has network problems.
If you check VMware Update Manager release notes for 5.1 (U1 or U2) or 5.5 (U1 or U2), you can find information about above issue and workaround:
You might not be able to enable the Update Manager plug-in on the vSphere Client
If the Update Manager database is located on a separate machine and the system DSN uses Windows authentication, you cannot enable the Update Manager plug-in on the vSphere Client. The error message you receive isThere was an error connecting to VMware vSphere Update Manager. Database temporarily unavailable or has network problems.
Workaround: Ensure that the Update Manager database uses SQL Server authentication.
It means that VMware hasn't resolved the problem for a long time and it is not possible to use Windows Authentication not only when the VUM database is located on a separate machine but also when a full SQL Server is installed on the same machine as VUM (I have faced this problem recently).
