High number of concurrent sessions open by CRI-O in port 5000 with STABLISHED status in OpenShift Container Platform 4.
Issue
The cluster is triggering session limits on the firewall. Observations indicate a high number of concurrent sessions, particularly towards the internal docker registry, generated by the CRI-O process on port 5000. The issue appeared after upgrading to OCP 4.13 from OCP 4.12.
Disparity in session counts among worker nodes, with some nodes showing significantly higher session counts. This is repeated in workers randomly.
Environment
- Red Hat OpenShift Container Platform 4.13.x [RHOCP]
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