Fixes#801. The solution is complicated by the fact that the Selector
field of Deployments is immutable. It would have been easy to just
make the Selectors of the main Concierge Deployment, the Kube cert agent
Deployment, and the various Services use more specific labels, but
that would break upgrades. Instead, we make the Pod template labels and
the Service selectors more specific, because those not immutable, and
then handle the Deployment selectors in a special way.
For the main Concierge and Supervisor Deployments, we cannot change
their selectors, so they remain "app: app_name", and we make other
changes to ensure that only the intended pods are selected. We keep the
original "app" label on those pods and remove the "app" label from the
pods of the Kube cert agent Deployment. By removing it from the Kube
cert agent pods, there is no longer any chance that they will
accidentally get selected by the main Concierge Deployment.
For the Kube cert agent Deployment, we can change the immutable selector
by deleting and recreating the Deployment. The new selector uses only
the unique label that has always been applied to the pods of that
deployment. Upon recreation, these pods no longer have the "app" label,
so they will not be selected by the main Concierge Deployment's
selector.
The selector of all Services have been updated to use new labels to
more specifically target the intended pods. For the Concierge Services,
this will prevent them from accidentally including the Kube cert agent
pods. For the Supervisor Services, we follow the same convention just
to be consistent and to help future-proof the Supervisor app in case it
ever has a second Deployment added to it.
The selector of the auto-created impersonation proxy Service was
also previously using the "app" label. There is no change to this
Service because that label will now select the correct pods, since
the Kube cert agent pods no longer have that label. It would be possible
to update that selector to use the new more specific label, but then we
would need to invent a way to pass that label into the controller, so
it seemed like more work than was justified.
Today is my last day working full time on Pinniped (for now). This change removes me from the MAINTAINERS.md and the website.
Signed-off-by: Matt Moyer <moyerm@vmware.com>
These fields were changed as a minor hardening attempt when we switched to Distroless, but I bungled the field names and we never noticed because Kapp doesn't apply API validations.
This change fixes the field names so they act as was originally intended. We should also follow up with a change that validates all of our installation manifest in CI.
Signed-off-by: Matt Moyer <moyerm@vmware.com>
Changes made to both components:
1. Logs are always flushed on process exit
2. Informer cache sync can no longer hang process start up forever
Changes made to concierge:
1. Add pre-shutdown hook that waits for controllers to exit cleanly
2. Informer caches are synced in post-start hook
Changes made to supervisor:
1. Add shutdown code that waits for controllers to exit cleanly
2. Add shutdown code that waits for active connections to become idle
Waiting for controllers to exit cleanly is critical as this allows
the leader election logic to release the lock on exit. This reduces
the time needed for the next leader to be elected.
Signed-off-by: Monis Khan <mok@vmware.com>
The kubelet will send the SIGTERM signal when it wants a process to
exit. After a grace period, it will send the SIGKILL signal to
force the process to terminate. The concierge has always handled
both SIGINT and SIGTERM as indicators for it to gracefully exit
(i.e. stop watches, controllers, etc). This change updates the
supervisor to do the same (previously it only handled SIGINT). This
is required to allow the leader election lock release logic to run.
Otherwise it can take a few minutes for new pods to acquire the
lease since they believe it is already held.
Signed-off-by: Monis Khan <mok@vmware.com>