Fix issue where wildcard routes get 503s intermittently.

[ramr]

As part of the resync processing, wildcard routes get a "HostAlreadyClaimed"
error and then later as part of the same event processing flow, the route gets re-added.
This results in a temporary outage (route returns 503s).

fixes #1660647 (https://bugzilla.redhat.com/show_bug.cgi?id=1660647)

@openshift/sig-network-edge PTAL Thx

Edited clarified route gets added in the same event processing flow.

[pravisankar]

/lgtm

[ironcladlou]

/approve

[openshift-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: ironcladlou, pravisankar, ramr

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[ramr]

/cherrypick release-3.10

[ramr]

/cherrypick release-3.9

[openshift-cherrypick-robot]

@ramr: #22087 failed to apply on top of branch "release-3.10":

error: Failed to merge in the changes.
Using index info to reconstruct a base tree...
M	pkg/router/controller/host_admitter.go
M	pkg/router/controller/host_admitter_test.go
Falling back to patching base and 3-way merge...
Auto-merging pkg/router/controller/host_admitter_test.go
CONFLICT (content): Merge conflict in pkg/router/controller/host_admitter_test.go
Auto-merging pkg/router/controller/host_admitter.go
Patch failed at 0001 Fix issue where wildcard routes get 503s intermittently. As part of the resync processing, wildcard routes get a "HostAlreadyClaimed" error and then later as part of the same event processing flow, the route gets re-added. This results in a temporary outage (route returns 503s).

In response to this:

/cherrypick release-3.10

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[openshift-cherrypick-robot]

@ramr: #22087 failed to apply on top of branch "release-3.9":

error: Failed to merge in the changes.
Using index info to reconstruct a base tree...
M	pkg/router/controller/host_admitter.go
M	pkg/router/controller/host_admitter_test.go
Falling back to patching base and 3-way merge...
Auto-merging pkg/router/controller/host_admitter_test.go
CONFLICT (content): Merge conflict in pkg/router/controller/host_admitter_test.go
Auto-merging pkg/router/controller/host_admitter.go
Patch failed at 0001 Fix issue where wildcard routes get 503s intermittently. As part of the resync processing, wildcard routes get a "HostAlreadyClaimed" error and then later as part of the same event processing flow, the route gets re-added. This results in a temporary outage (route returns 503s).

In response to this:

/cherrypick release-3.9

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.