2022-01-13: Chef client failures

Current Status

Deploying a fix for the change in UA behaviour from https://gitlab.com/gitlab-cookbooks/gitlab-server/-/merge_requests/308

Currently we are having difficulty rolling out the change due to the berksfile wanting to update several cookbooks to versions that are too new. Working to fix the dependencies so we can rollout the change.

Initial Investigation:

129 chef errors so far.

Error which appears to be causing the chef-client failures is: Error executing action run on resource 'execute[enroll node to ubuntu advantage]'

More information will be added as we investigate the issue.

Timeline

Recent Events (available internally only):

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

All times UTC.

2022-01-13

• 16:45 - @nnelson declares incident in Slack.
• 18:00 - We think ubuntu-advantage-tools was upgraded, and the newest upgrade now uses a non-zero exit code. Looking into changing parameters as to when token is attached, where it is only attached depending on ubuntu-advantage status.
• 18:20 - Committed a change to only attach ubuntu advantage if currently unattached https://gitlab.com/gitlab-cookbooks/gitlab-server/-/merge_requests/308
• 20:23 - Updated exporters cookbook to use the new changes gitlab-cookbooks/gitlab-exporters!252 (merged)
• 21:40 - Released new version of the exporters cookbook: gitlab-cookbooks/gitlab-exporters!253 (merged)
• 22:36 - New version of exporters cookbook with fixed cron version gitlab-cookbooks/gitlab-exporters!254 (merged)
• 23:10 - New version of exporters with a few more fixed cookbook dependency versions: gitlab-cookbooks/gitlab-exporters!255 (merged)

2022-01-14

• 03:54 - gitlab-cookbooks/gitlab-exporters!256 (merged) rolled out to all envs. Errors https://prometheus.gprd.gitlab.net/graph?g0.expr=chef_client_error&g0.tab=0&g0.stacked=0&g0.show_exemplars=0&g0.range_input=1h going down.

Takeaways

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Corrective Actions

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Incident Review

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Customer Impact

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What were the root causes?

gitlab-cookbooks/gitlab-exporters!254 (merged)

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Incident Response Analysis

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Post Incident Analysis

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What went well?

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Guidelines

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Resources

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