a systemd.socket is started by the according systemd.service

[tuxmea]

No description provided.

[bastelfreak]

Did you check if this works?
It looks like the package only provide a multiinstance unit: https://centos.pkgs.org/8-stream/centos-appstream-x86_64/tang-7-8.el8.x86_64.rpm.html

[tuxmea]

It should work: /usr/lib/systemd/system/tangd@.service

[jhoblitt]

Is there a reason to move switch from socket activation?

[tuxmea]

Is there a reason to move switch from socket activation?

Yes: https://www.freedesktop.org/software/systemd/man/systemd.socket.html

For each socket unit, a matching service unit must exist, describing the service to start on incoming traffic on the socket (see systemd.service(5) for more information about .service units).

[jhoblitt]

@tuxmea Generally, when using systemd socket activation the service unit itself is disabled.

[tuxmea]

@tuxmea Generally, when using systemd socket activation the service unit itself is disabled.

changed back to socket.

[bastelfreak]

verified that this works:

[root@rocky-8gb-fsn1-1 ~]# systemctl status tangd.socket
● tangd.socket - Tang Server socket
     Loaded: loaded (/usr/lib/systemd/system/tangd.socket; disabled; preset: disabled)
    Drop-In: /etc/systemd/system/tangd.socket.d
             └─override.conf
     Active: active (listening) since Wed 2023-10-25 16:14:27 UTC; 4min 24s ago
      Until: Wed 2023-10-25 16:14:27 UTC; 4min 24s ago
     Listen: [::]:7500 (Stream)
   Accepted: 0; Connected: 0;
      Tasks: 0 (limit: 49300)
     Memory: 8.0K
        CPU: 818us
     CGroup: /system.slice/tangd.socket

Oct 25 16:14:27 rocky-8gb-fsn1-1 systemd[1]: Listening on Tang Server socket.
[root@rocky-8gb-fsn1-1 ~]# systemctl cat tangd@.service
# /usr/lib/systemd/system/tangd@.service
[Unit]
Description=Tang Server

[Service]
StandardInput=socket
StandardOutput=socket
StandardError=journal
ExecStart=/usr/libexec/tangd /var/db/tang
User=tang
User=tang
[root@rocky-8gb-fsn1-1 ~]# systemctl cat tangd.socket
# /usr/lib/systemd/system/tangd.socket
[Unit]
Description=Tang Server socket

[Socket]
ListenStream=80
Accept=true

[Install]
WantedBy=sockets.target

# /etc/systemd/system/tangd.socket.d/override.conf
[Socket]
ListenStream=
ListenStream=7500
[root@rocky-8gb-fsn1-1 ~]# curl http://127.0.0.1:7500/adv
{"payload": "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", "protected": "eyJhbGciOiJFUzUxMiIsImN0eSI6Imp3ay1zZXQranNvbiJ9", "signature": "AOth4yxhO34NIlo4xocAKuPsKhOE_WKhQToFPsU-Eg7JhsDQehYwIkJJQKqmSVRDv1kwrmhWoR9it0cfjUyrlA9mAaZgVWW1HUDyJUp6cawKw-BjektGmzneWYztfRgKNP_VO8YIeekWS3hdaKL0gXcgUWhDLCAZcjbRgm7JPhg0Z2t_"}[root@rocky-8gb-fsn1-1 ~]#