The Impala statestore keeps track of how MANY impalad nodes are currently available. You can see this information through the statestore web interface. For EXAMPLE, at the URL http://statestore_host:25010/metrics you MIGHT see lines like the following:

statestore.live-backends:3

statestore.live-backends.list:[host1:22000, host1:26000, host2:22000]

The number of impalad nodes is the number of list ITEMS referring to port 22000, in this case two. (Typically, this number is one less than the number reported by the statestore.live-backends line.) If an impalad node became unavailable or came back after an outage, the information reported on this page would change appropriately.

The Impala statestore keeps track of how many impalad nodes are currently available. You can see this information through the statestore web interface. For example, at the URL http://statestore_host:25010/metrics you might see lines like the following:

statestore.live-backends:3

statestore.live-backends.list:[host1:22000, host1:26000, host2:22000]

The number of impalad nodes is the number of list items referring to port 22000, in this case two. (Typically, this number is one less than the number reported by the statestore.live-backends line.) If an impalad node became unavailable or came back after an outage, the information reported on this page would change appropriately.