While listing the status of PMDBs to check on their health, they periodically are coming back as not responding.
The `sepmd -e pmdbname` command was used to list the errors from the PMDB, which included a large number of errors communicating with subscribers. When the `sepmd -L pmdbname` command was run, some of the subscribers were from decommissioned servers.
Use the `sepmd -u pmdbname subscriber` command to remove decommissioned servers from the subscribers list for the PMDB to improve the PMDB's performance.