Why is there a following error in 'lookup' command "Lookups: The lookup table 'event_time_field=temp_time' does not exist or is not available"?

[woodcock]

Evidently this is well-known in support circles but not on the internet yet, so I am sharing my pain for your gain.
We just installed ES and everything was OK except for the following strangenesses:

ES Notables are firing but not showing up on Security Posture ( index=notables shows plenty of action).
I am getting this error on several screens including Audit -> ES Configuration Health (which will not run at all):

Error in 'lookup' command: Lookups: The lookup table 'event_time_field=temp_time' does not exist or is not available. 

In ad-hoc search, click on the v and select the Create Notable Event action under Event Action menu and notice that there is no Save button.

What is going on here?

[woodcock · Accepted solution]

Evidently these are all symptoms of running ES version 5.1 on version of Splunk core < 7.1.0. Indeed, we are running v6.6.8. So now I need to decide if I should unisntall ES and install version 5.0 or upgrade core to v7.1.2. I am leaning towards the latter and hoping that I can avoid having to reinstall ES. I will report back with my findings after I get done.

[woodcock]

OK, I upgraded the cluster to v7.1.2 and all of the problems listed disappeared, so clearly that was the entire problem. The installer really should have complained and not allowed itself to proceed. At least now the symptoms are clearly documented here.