Dear MoveComms,
We are planning a datacentre switchover for the week of October 26st (week 44) with the following schedule:
- Services: Tuesday, 27 October 2026 @15:00 UTC
- Traffic: Tuesday, 27 October 2026 @15:00 UTC
- MediaWiki: Wednesday, 28 October 2026 @15:00 UTC (this is the read-only time)
- Deployment Server: Thursday, 29 October 2026 @09:00 UTC
- eqiad repool: Thursday, 5th November 2026 @14:00 UTC
The expected impact is 2-3 minutes of read-only on Wednesday, 28 October 2026 @ 15:00 UTC.
We continue to follow the process described in Recurring, Equinox-based, Data Center Switchovers, in particular:
- There is no switchback! We are staying in codfw until the next switchover.
- Future switchovers are predictable and take place every 6 months; always on the week of an equinox.
Let ServiceOps know if you need more info on the changes.
Thank you!
Planning
As soon as the task is received by Movement Communications
- Ask SRE if anything major changed since the last time (noticeable things that are worth being announced).
- If yes, update the process or the message.
- Confirm when the wikis will be in read-only - 28 October 2026 @ 15:00 UT
- Add the date to Asana, with a link to this task
- Added as tentative
Three weeks before
- Add to Tech News the initial information in this week's issue (before Friday evening), reuse this message
- Update the message to communities
- Check on dates and time (dates are formatted <code>YYYY-MM-DDTHH-SS</code>, like 2026-09-23T14:00; don't touch what's around)
- Once dates and times are edited, check (in preview mode) if the Zonestamp links display the right time and date for your timezone.
- Check on links, have they changed?
- Edit qqq messages with the new Zonestamp link (reuse the one from the page)
-
Have the message being translated by emailing both:- translators-l for translations
- If relevant, mention Daylight saving time in this message
- wikitech-ambassadors for information and translations
- translators-l for translations
- Monitor the message's talk page
Two weeks before
- Regarding the Central Notice Banner:
- Edit the campaign (to unarchive)
- Set the starting time for the campaign is 30 minutes before the scheduled time
- Set the ending time for the campaign is 2 minutes after the scheduled time
- Set the campaign as "enabled."
- Other settings are "maintenance banner" and "emergency". The banner used is read_only_banner
- Add the banner to https://meta.wikimedia.org/wiki/CentralNotice/Calendar
- Edit the Banner
- Check if the banner redirects to https://meta.wikimedia.org/wiki/Tech/Server_switch
- Check on the banner is the hour is correct
- Edit the campaign (to unarchive)
-
Add to Tech News that this is happening next week. reuse this message)
The week before
- Inform:
- wikitech-ambassadors and translators-l once again (reminders)
- SRE informs staff on Slack
- Add to the news on the Meta front page (reuse this message)
- Check on translations
- Using MassMessage, send the message to non-technical village pumps
- Edit Tech News to day that it is happening this week ([https://meta.wikimedia.org/w/index.php?title=Tech/News/2026/13&diff=prev&oldid=30274528 reuse this message])
- Ask our SRE contact on how they will Movement Communication of the progress of the process, and through which channel (Slack being prefered).
The week it happens
- Confirm with SRE how the first steps happen on the day before.
- monitor the wikis to check if anyone has questions
- if relevant, when the read-only is done and confirmed by SRE's spokeperson, remove the banner.
The week after, maximum
- Debrief how it went, and document (comment on this task)
- If not done, archive the campaign
