Unneeded Authentication Caching
SSSD (System Security Services Daemon) is a highly capable service in Ubuntu and enterprise Linux distributions used to manage remote directory services and authentication mechanisms. It acts as a bridge between the Linux system and remote identity providers like LDAP, Active Directory (AD), or Kerberos. It caches credentials locally so users can still log in even if the remote authentication server temporarily goes down.
While SSSD is absolutely critical for servers joined to a corporate Active Directory domain, it is completely useless on a standalone, local server that only uses local user accounts (configured in /etc/passwd). Leaving the sssd daemon running on a local machine wastes memory and CPU cycles as it periodically attempts to check its configuration for remote providers that don’t exist. If your server is not joined to a domain, you should disable it.
How to Disable the SSSD Daemon
You can stop and disable the service using systemctl.
- Open your Ubuntu Terminal or connect via SSH.
- Stop the daemon immediately:
sudo systemctl stop sssd.service- Disable the service to prevent it from starting automatically on boot:
sudo systemctl disable sssd.service- (Optional) Mask the service to ensure no other package accidentally triggers it:
sudo systemctl mask sssd.serviceYour server will now rely entirely on local authentication files, eliminating the overhead of the remote identity caching daemon.