I've self-hosted Mattermost since 2019 (originally to escape Slack’s retention limits for family chat; logistics, photos, random history). It was a huge hurdle getting them all on Slack, and then moving them again to Mattermost.
This morning, I upgraded our long-running Omnibus install from v10.9.1 → v11, following Mattermost's explicit deprecation notice[0] and recommendation to switch to standard Binary/Docker/k8s/etc deployment.
Upgrade went cleanly:
Postgres migration fine
Data still present in DB
Service came back up in minutes
Post-restart the UI shows:
“10,000-message limit reached. Messages sent before May 16, 2023 are hidden.”
Clarification: no DELETE FROM anywhere. All rows still in PostgreSQL. The limit is UI/view-layer only, retroactively applied after "upgrade".
Checked beforehand:
- Omnibus deprecation announcement [0]
- v11 upgrade guide [4]
- Admin console nags/links
None mentioned that an in-place upgrade would activate hard visibility caps on pre-existing data. First indication was the running instance after restart.
Currently (as of 2026-01-12_1337):
- https://mattermost.com/pl/mattermost-entry-limits (In-App Link to Limits) [1] 404s (Page not found)
- https://mattermost.com/pricing/ (also an in-app link) [2] only has “Contact Sales”, no enumerated limits (or prices).
- https://docs.mattermost.com/administration-guide/manage/product-limits.html [3], used Kagi to find this, no mention of message limits
I'm happy to pay for supported software. The friction is the surprise enforcement on self-hosted + self-managed DB. Upgrade path quietly turned history into a licensed feature without forewarning in the upgrade docs.
For now:
We're leaving the v11 instance up (secure, current messages flow normally). The system console and dashboard aren't loading correctly, possibly due to the message limits, possibly due to other issues.
I'm thinking some sort of rsync + static HTML archive of current visible history + DB dump for offline search. I'm afraid future policy changes could further gate access, and would love recommendations.
Posting mostly as warning to other long-running Omnibus users (small groups, families, hobby servers) who are about to upgrade and may not expect the view limit to kick in retroactively.
If your install predates the limit introduction and has >10k messages, test upgrade in staging first—or assume the docs are incomplete on enforcement timing. Don't expect to get help in the forum [5], the last post (before mine today) is from October 2025 and the moderator directed to the Gitlab Omnibus thread which doesn't provide details on message limits or answer the other questions.
Curious if others hit surprises on the v11 "upgrade", and if anyone has any suggestions.
[0] https://github.com/mattermost/mattermost-omnibus
[1] https://mattermost.com/pl/mattermost-entry-limits
[2] https://mattermost.com/pricing/
[3] https://docs.mattermost.com/administration-guide/manage/product-limits.html
[4] https://docs.mattermost.com/deployment-guide/server/deploy-linux.html
[5] https://forum.mattermost.com/t/clarification-needed-for-the-upgrade-to-v11/25344
