The “last Heartbeat” is the last time that the node reported that it was up and running. Every 5 minutes, each node from the cluster signals that it is up and running and updating its last heartbeat.
If one node is not updating the last heartbeat for more than 5 minutes, a warning icon will be displayed in the [UI] –> [‘Admin’ tab] -> [‘High Availability’ page] –> [as in the following documentation page]:
Usually, when there is an issue with one of the servers, the state of the server in the HA page is kept in a ‘Running’ state. However, since the server Heartbeat does not get updated for a long interval of time, it is displayed in red with a warning sign.
If you wish to know if your server is currently running, you should use API calls such as the System Health Ping REST call in order to ping the node which you think has an issue.
If you wish to know when was the last time that the server reported that it was running, you can monitor the artifactory_server tables.