Empty Logs in ACS 5.1

Cisco's latest version of ACS, 5.1, is a massive improvement on previous versions and has come from a ground-up rebuild of the entire server.  I've used it in a recent deployment for TACACS+ AAA on network devices, plus 802.1x authentication of WLAN users.  So far I've found it pretty easy to use, but I was puzzled today, when perusing the logs to try and figure out why switches weren't authenticating users via TACACS, to find empty logs!

As it turns out, this was due to some (or all) of the view processes not running.  To get them running again, log into the ACS console via SSH and use the following command:

ACS/admin# acs start ?
  adclient           Start adclient
  database           Start database
  management         Start management
  runtime            Start runtime
  view-alertmanager  Start view-alertmanager
  view-collector     Start view-collector
  view-database      Start view-database
  view-jobmanager    Start view-jobmanager
  view-logprocessor  Start view-logprocessor
                 Carriage return.