The cancelpublication tool can be used to cancel long-running publications that prevent users from publishing other content. A publication that should be canceled has to be in on of the stages:

When the publication has reached the stage started, that means it is running, it is not possible to cancel it anymore.

Long-running publications can occur when you have a complex content model structure with many links. You publish a deleted content item that is linked with many other content items, for example. This would lead to a long running dependencies checking stage which you can cancel with the tool.

So this is an emergency tool which you will need in exceptional cases only.

You can obtain the IDs of the running publications with the publications utility (see Section 3.13.1.5, “Publications”).

usage: cm cancelpublication -u <user> [other options] 
       <publicationId> ...
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