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

The procedures in this runbook require admin permissions to complete.

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

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Overview

If DNS (or an 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.

Fixing

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

That doesn't always work -- in extreme cases you might also need to actively delete the cache files.

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

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