You are browsing a read-only backup copy of Wikitech. The live site can be found at wikitech.wikimedia.org

Incidents/2021-11-02 Cloud VPS networking

From Wikitech-static
Jump to navigation Jump to search

document status: in-review

Summary and Metadata

The metadata is aimed at helping provide a quick snapshot of context around what happened during the incident.

Incident ID 2021-11-02 Cloud VPS networking UTC Start Timestamp: 2021-11-02 11:35:00
Incident Task T294853 UTC End Timestamp 2021-11-02 13:20:00
People Paged 0 Responder Count 3: Dcaro, Aborrero, Majavah (+ volunteers reporting on IRC)
Coordinator(s) No ICs Relevant Metrics / SLO(s) affected No SLO defined
Summary: For about 1 hour and 40 minutes, Toolforge services and VMs in Cloud VPS may have experienced connectivity issues

After a kernel upgrade for several Cloud VPS network components (cloudnet, cloudgw servers; see T291813), we found problems with Toolforge NFS in Kubernetes. Later LDAP connections were found to be affected. Eventually it turned out to be a problem with all ingress traffic to the network edge for cloud VMs (except those with floating IPs, which were unaffected). The issue was resolved by rolling back the kernel upgrade.

Impact: For about 1 hour and 40 minutes, Toolforge services and VMs in Cloud VPS may have experienced connectivity issues

Scorecard

Question Score Notes
People Were the people responding to this incident sufficiently different than the previous five incidents? (score 1 for yes, 0 for no) 1
Were the people who responded prepared enough to respond effectively (score 1 for yes, 0 for no) 0
Were more than 5 people paged? (score 0 for yes, 1 for no) 1
Were pages routed to the correct sub-team(s)? (score 1 for yes, 0 for no) 1
Were pages routed to online (business hours) engineers? (score 1 for yes,  0 if people were paged after business hours) 1
Process Was the incident status section actively updated during the incident? (score 1 for yes, 0 for no) 0
Was the public status page updated? (score 1 for yes, 0 for no) 0
Is there a phabricator task for the incident? (score 1 for yes, 0 for no) 1
Are the documented action items assigned?  (score 1 for yes, 0 for no) 1
Is this a repeat of an earlier incident (score 0 for yes, 1 for no) 0
Tooling Was there, before the incident occurred, open tasks that would prevent this incident / make mitigation easier if implemented? (score 0 for yes, 1 for no) 0
Were the people responding able to communicate effectively during the incident with the existing tooling? (score 1 for yes, 0 or no) 1
Did existing monitoring notify the initial responders? (score 1 for yes, 0 for no) 1
Were all engineering tools required available and in service? (score 1 for yes, 0 for no) 1
Was there a runbook for all known issues present? (score 1 for yes, 0 for no) 0
Total score 9

Actionables

  • Improve automated testing and monitoring of cloud networking, T294955
  • Set up static route for cr-codfw, T295288
  • Avoid keepalived flaps when rebooting servers, T294956