When running remctld -h on Debian bookworm I see this:
Usage: remctld <options>
Options:
-b <addr> Bind to a specific address (may be given multiple times)
-d Log verbose debugging information
-F Run in the foreground instead of forking and exiting
-f <file> Config file (default: /etc/remctl/remctl.conf)
-h Display this help
-m Stand-alone daemon mode, meant mostly for testing
-P <file> Write PID to file, only useful with -m
-p <port> Port to use, only for standalone mode (default: 4373)
-S Log to standard output/error rather than syslog
-s <service> Service principal to use (default: host/<host>)
-v Display the version of remctld
-Z Raise SIGSTOP once ready for connections
Supported ACL methods: file, princ, deny, localgroup, regex
However, running man remctld shows (in part) this:
-k keytab
[2.8] Use keytab as the keytab for server credentials rather than the system default or the value of the KRB5_KTNAME
environment variable. Using -k just sets the KRB5_KTNAME environment variable internally in the process.
Suggestion, add the -k option information to the output of remctld -h.