Portal:Cloud VPS/Admin/Runbooks/Refresh sssd caches

From Wikitech
The procedures in this runbook require root (sudo) permissions to complete.

How to clear sssd caches (hosts, groups, etc).


If DNS or LDAP change needs a quick update on a Cloud VPS VM that runs sssd, sometimes waiting for the cache to expire is not something you want to do for whatever reason. This applies if the host is not running the nscd or a similar OTHER cache for this kind of information. If you are running nscd, you'll have to clear that instead and/or as well (eg. nscd -i hosts). Anyone operating a Cloud VPS instance with sudo permissions can accomplish this.


  1. Make sure the Debian package sssd-tools is installed. If it is not installed on this VM, run sudo apt-get install sssd-tools Requires root/sudo permissions
  2. Run sudo -i sss_cache -E to invalidate all caches. Requires root/sudo permissions

The programmatic cache purge does not always work -- in extreme cases you might also need to actively delete the cache files:

$ sudo systemctl stop sssd
$ sudo rm -rf /var/lib/sss/db/*
$ sudo systemctl restart sssd

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