When the allocation is stopped, we deregister the service in the alloc runner's
`PreKill` hook. This ensures we delete the service registration and wait for the
shutdown delay before shutting down the tasks, so that workloads can drain their
connections. However, the call to remove the workload only logs errors and never
retries them.
Add a short retry loop to the `RemoveWorkload` method for Nomad services, so
that transient errors give us an extra opportunity to deregister the service
before the tasks are stopped, before we need to fall back to the data integrity
improvements implemented in #20590.
Ref: https://github.com/hashicorp/nomad/issues/16616
* services: always set deregister flag after deregistration of group
This PR fixes a bug where the group service hook's deregister flag was
not set in some cases, causing the hook to attempt deregistrations twice
during job updates (alloc replacement).
In the tests ... we used to assert on the wrong behvior (remove twice) which
has now been corrected to assert we remove only once.
This bug was "silent" in the Consul provider world because the error logs for
double deregistration only show up in Consul logs; with the Nomad provider the
error logs are in the Nomad agent logs.
* services: cleanup group service hook tests
* nsd: block on removal of services
This PR uses a WaitGroup to ensure workload removals are complete
before returning from ServiceRegistrationHandler.RemoveWorkload of
the nomad service provider. The de-registration of individual services
still occurs asynchrously, but we must block on the parent removal
call so that we do not race with further operations on the same set
of services - e.g. in the case of a task restart where we de-register
and then re-register the services in quick succession.
Fixes#15032
* nsd: add e2e test for initial failing check and restart
This PR implements support for check_restart for checks registered
in the Nomad service provider.
Unlike Consul, Nomad service checks never report a "warning" status,
and so the check_restart.ignore_warnings configuration is not valid
for Nomad service checks.
This PR introduces the `address` field in the `service` block so that Nomad
or Consul services can be registered with a custom `.Address.` to advertise.
The address can be an IP address or domain name. If the `address` field is
set, the `service.address_mode` must be set in `auto` mode.
