2022-08-31: LoggingVisibilityDiminished
Incident Roles
The DRI for this incident is the incident issue assignee, see roles and responsibilities.
Roles when the incident was declared:
- Incident Manager (IMOC): @johnhope,
@wortschi (Shadow)
- Engineer on-call (EOC): @igorwwwwwwwwwwwwwwwwwwww
Current Status
We've increased the total_shards_per_node
to 3
for the warm nodes, and we started seeing indexes being rolled over and our hot nodes disk being freed up, which freed up the CPU and resulted into it catch up on the backlog of logs.
Summary for CMOC notice / Exec summary:
- Customer Impact: None
- Service Impact: ServiceLogging
- Impact Duration: start time UTC - end time UTC ( duration in minutes )
- Root cause: Miss configuration of
total_shards_per_node
of the warm nodes which resulted into indexes never being removed from thehot
nodes to thewarm
nodes.
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.
2022-08-31
-
08:01
- @igorwwwwwwwwwwwwwwwwwwww declares incident in Slack.
Create related issues
Use the following links to create related issues to this incident if additional work needs to be completed after it is resolved:
Takeaways
- We can use
GET _cluster/health
using the dev console or the API Console to get a better understand of how the cluster is doing. - We can use
GET _all/_ilm/explain
andGET _all/_ilm/explain?only_errors
to better understand the errors with have forilm
.
Corrective Actions
Corrective actions should be put here as soon as an incident is mitigated, ensure that all corrective actions mentioned in the notes below are included.
- Make disk saturation pageable, and add a runbook for it
👉 gitlab-com/runbooks!4976 (merged)
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Incident Review
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Customer Impact
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Who was impacted by this incident? (i.e. external customers, internal customers)
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Incident Response Analysis
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Post Incident Analysis
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