Apicast is returning 503 on requests when it is configured to support TLS, with the following error log repeated multiple times.

 2021/05/24 10:06:19 [error] 21#21: *15 attempt to send data on a closed socket: u:00007FF7F60D13C8, c:0000000000000000, client: 10.130.0.1, server: _, request: "GET /get?user_key=32c367360d3da36313bd8e3287bac9cb HTTP/1.1", host: "12489.3scale.apps.ocp.api-qe.eng.rdu2.redhat.com"

The 503 is returned only when the service configurations are downloaded. When these are cached, the 200 is returned as expected.
Based on the other logs, the issue seems to be related to the dns.

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