Don't sync ZoneIngresses

[lahabana]

Description

There's no need to do this.

In the end all we need is:

1. other zones need a list of host:port that they can reach the zone (at the start a single one is enough to support - the LB to the zone).
2. persist this in the zone object
3. each zone manages offline zones directly from the client (combination of tcp retries and circuitbreaker). Active healthchecking is tricky because

The zone Object would look like:

type: Zone
name: zone-1
spec:
  endpoints:
  - address: aws-lb:9901

Positives:

• Much easier for remote zones to build remote endpoints (it's a single zone object not many zoneIngresses)
• Less moving stuff (zoneIngress can still be synced to global but they don't need to be pushed to zones)

Negatives:

• Need to find a good healthchecking story as we need to handle the case that a zone disconnected from global doesn't mean that traffic can't be routed to it.

[jakubdyszkiewicz]

Questions:

• Where to compute list of endpoints in Zone? Currently we don't sync Zone object. We can compute this on global and sync Zone object from global to zone.

[github-actions[bot]]

This issue was inactive for 90 days. It will be reviewed in the next triage meeting and might be closed. If you think this issue is still relevant, please comment on it or attend the next triage meeting.