2022-05-01: Pods failing to initialize due to missing calico plugin on 1 GKE node

Incident DRI

@msmiley - EOC

Current Status

One of the GKE nodes in the node pool api-1 (used for webservice-api pods) had failed to install the calico binary into /home/kubernetes/bin.

Consequently, any pods scheduled to that node were doomed to fail while trying to initialize their networking.

This is a known issue with GKE nodes, and GCP Support expects a fix in the near future (GCP ticket - internal only).

For reference, the calico plugin is supposed to be installed during GKE node initialization by the calico-node-XXXXX pod. Restarting that pod on the affected GKE node has in the past been a viable work-around. In this case, the node was scaled down before we got to try that.

More background on the problem is available in the following related incident from 2 weeks ago: #6854 (comment 915580011)

Summary for CMOC notice / Exec summary:

1. Customer Impact: No customer impact. Only 1 GKE node out of 20 was unable to create additional pods for the api fleet, but other existing and new nodes remained viable (so autoscaling could still do its job).
2. Service Impact: ServiceAPI
3. Impact Duration: none
4. Root cause: RootCauseKnown-Software-Issue - This is a defect where GKE node initialization fails to install a critical component (the calico networking plugin) when provisioning a new GKE node. The same problem likely affects other GCP customers too. Hopefully the above notes are useful to them as a work-around until GKE fixes the defect.

Timeline

Recent Events (available internally only):

• Deployments
• Feature Flag Changes
• Infrastructure Configurations
• GCP Events (e.g. host failure)
• Gitlab.com Latest Updates

All times UTC.

2022-05-01

• 17:28 - @msmiley declares incident in Slack.

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