Updating LbEndpoint metadata causes connection churn

[thejas-stripe]

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Title: Updating LbEndpoint metadata causes connection churn

Description: When envoy receives a ClusterLoadAssignment with same endpoints but with updated metadata , envoy tearsdown existing connection and re-establishes a new one with all the endpoints. Is this the expected ?
Or is there a relation with any other configuration which causes this connection churn ?
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Any extra documentation required to understand the issue.

[htuch]

Is this LbEndpoint metadata or LocalityLbEndpoints?

[thejas-stripe]

@htuch
Its LbEndpoint metadata - https://www.envoyproxy.io/docs/envoy/latest/api-v3/config/endpoint/v3/endpoint_components.proto#config-endpoint-v3-lbendpoint

I'm updating the filter_metadata in the metadata structure, which causes connection churn.

[thejas-stripe]

The metada value is similar to this

old

"metadata": {
           "filter_metadata": {
            "envoy.lb": {
             "filed1": "value1",
            }
           }

Updated metadata will look like this

"metadata": {
           "filter_metadata": {
            "envoy.lb": {
             "filed1": "value1",
             "field2": "value2"
            }
           }

[htuch]

@cpakulski @adisuissa