Remove Custos from a host

Use the built-in uninstaller first.

sudo /usr/local/bin/custosd uninstall

uninstall notifies the control plane using the host’s daemon identity, marks the host revoked, stops the systemd service, removes the sshd hook, and removes the installed binary. Add --purge to also remove the local daemon state and the custos system user:

sudo /usr/local/bin/custosd uninstall --purge

If the control plane is unreachable, skip the decommission request and revoke the host manually from the control plane afterwards:

sudo /usr/local/bin/custosd uninstall --purge --skip-control-plane

Only use --skip-control-plane when you intend to revoke the host by hand. Until it is revoked, the control plane still counts that machine as having an active host, and the machine cannot re-enroll.

What the uninstaller removes

/etc/ssh/sshd_config.d/70-custos.conf
/etc/systemd/system/custosd.service
/usr/local/bin/custosd
/usr/local/bin/custosd.prev
/var/lib/custos — only with --purge
the custos system user — only with --purge

Verifying by hand

To check for and remove any remaining local traces:

sudo systemctl disable --now custosd 2>/dev/null || true
sudo rm -f /etc/ssh/sshd_config.d/70-custos.conf
if sudo sshd -t; then
  sudo systemctl reload ssh 2>/dev/null || sudo systemctl reload sshd
fi
sudo rm -f /etc/systemd/system/custosd.service
sudo systemctl daemon-reload
sudo rm -f /usr/local/bin/custosd /usr/local/bin/custosd.prev
sudo rm -rf /var/lib/custos /run/custos
sudo userdel custos 2>/dev/null || true
sudo groupdel custos 2>/dev/null || true

If app service users were added to the custos group for custosd exec, remove that membership before deleting the group:

getent group custos
sudo gpasswd -d <app-service-user> custos

What is left behind

System logs and shell history are outside the daemon’s state. To remove those too, delete the relevant shell history entries and rotate or vacuum systemd journals according to your host’s logging policy.

Be careful with journalctl --vacuum-*: it affects the whole system journal, not only Custos entries.

Audit records on the control plane are deliberately retained. A revoked host keeps its history.

Getting started

Concepts

Control plane

Hosts

Web app

Guides

Operations

Reference

Internals

Remove Custos from a host

What the uninstaller removes

Verifying by hand

What is left behind

​What the uninstaller removes

​Verifying by hand

​What is left behind

What the uninstaller removes

Verifying by hand

What is left behind