This utility kills specified sessions on the Content Server. You can obtain the IDs of the open sessions with the sessions utility (see Section 3.13.1.8, “Sessions”).

Well-behaved clients terminate their sessions, and the content server automatically kills sessions which don't respond within a certain timeout. So this is an emergency tool which you will need in exceptional cases only.

usage: cm killsession -u <user> [other options] <session> ...
available options:
 -d,--domain <domain name>   domain for login (default=<builtin>)
 -p,--password <password>    password for login
 -u,--user <user name>       user for login (required)
 -url <ior url>              url to connect to
 -v,--verbose                enables verbose output

That is, killsession has none but the standard options.