Incident Report: 20230109

Incident Report
ITS replaced some networking gear and broke some routes. Sad panda.
Summary
Severity	High
Impact	Medium (anything URY-related unavailable for around ~8 hours)
Event Start	2023-01-09 09:30
Event End	2023-01-09 17:19
Recurrence Mitigation	All necessary changes implemented
Contacts
Recovery Leader	Joseph Sisson (JS)
Other Attendees	Michael Grace (MG), Marks Polakovs (MP)

Chronicle of Events

(All times GMT)

Early in the morning of the first day of the first week of term, IT Services (as we later found out) replaced some networking equipment in the Vanbrugh area, and may have incorrectly set some static routes. The first we found out about this is at 9:30, when all of our monitoring pinged that URY had dropped off the face of the internet.

Much scrambling and some (ultimately futile) reboots later, we narrowed down the state of the network to:

• Anything with a 144.32.64.160/27 IP (so all of URY) could send packets out of URY, but no packets would make it in.

• With the exception of uryfw0 which has a separate IP (144.32.109.64).
• Traceroutes showed the packets getting into a loop somewhere in Berrick Saul.

• This meant that the website and online streams were down.
• We could carry on broadcasting on AM, but FM failed

• MP later diagnosed the FM issue to be a dependency on audio.ury.org.uk for the backup feed, and restored FM at 14:39.

• You really don't want to know how... no, seriously, it's horrible...

An ITS ticket was filed at 12:12, and at around 17:14 service was restored.

Lessons Learned

TODO