I got this on one of my daemons after upgrading today:
$ sudo systemctl status shadowsocks-libev.service
● shadowsocks-libev.service - Shadowsocks-libev Default Server Service
Loaded: loaded (/lib/systemd/system/shadowsocks-libev.service; enabled; vendor preset: enabled)
Active: failed (Result: exit-code) since Wed 2020-10-21 16:00:37 +0330; 14s ago
Docs: man:shadowsocks-libev(8)
Process: 354 ExecStart=/usr/bin/ss-local -c $CONFFILE $DAEMON_ARGS (code=exited, status=218/CAPABILITIES)
Main PID: 354 (code=exited, status=218/CAPABILITIES)
اكتبر 21 16:00:37 vero systemd[1]: Started Shadowsocks-libev Default Server Service.
اكتبر 21 16:00:37 vero systemd[354]: shadowsocks-libev.service: Failed to apply ambient capabilities (before UID change): Invalid argument
اكتبر 21 16:00:37 vero systemd[354]: shadowsocks-libev.service: Failed at step CAPABILITIES spawning /usr/bin/ss-local: Invalid argument
اكتبر 21 16:00:37 vero systemd[1]: shadowsocks-libev.service: Main process exited, code=exited, status=218/CAPABILITIES
اكتبر 21 16:00:37 vero systemd[1]: shadowsocks-libev.service: Failed with result 'exit-code'.
It’s either caused by systemd upgrade or the kernel. I found a similar thread on Archlinux here: [ArchLinux] systemd upgrade breaks daemons [SOLVED] - ODROID
