sonic-buildimage/files/build_templates/tacacs-config.service

[Unit]
Description=TACACS application
Requires=updategraph.service
After=updategraph.service

[Service]
Type=oneshot
ExecStart=/usr/bin/updategraph apply_tacacs
RemainAfterExit=yes
Add service to restore TACACS from old config (#7560) (#8233) Why I did it In upgrade scenarios, where config_db.json is not carry forwarded to new image, it could be left w/o TACACS credentials. Added a service to trigger 5 minutes after boot and restore TACACS, if /etc/sonic/old_config/tacacs.json is present. How I did it By adding a service, that would fire 5 mins after boot. This service apply tacacs if available. How to verify it Upgrade and watch status of tacacs.timer & tacacs.service You may create /etc/sonic/old_config/tacacs.json, with updated credentials (before 5mins after boot) and see that appears in config & persisted too. 2021-08-02 12:33:55 -05:00			`[Unit]`
			`Description=TACACS application`
			`Requires=updategraph.service`
			`After=updategraph.service`

			`[Service]`
			`Type=oneshot`
			`ExecStart=/usr/bin/updategraph apply_tacacs`
			`RemainAfterExit=yes`