Hi,

 apt-mirror(1) partially reads:

COMMENTS
       apt-mirror uses /etc/apt/mirror.list as a configuration
       file.  By default it is tuned to official Debian or Ubuntu
       mirrors. Change it for your needs.

       After you setup the configuration file you may run as root:

           # su - apt-mirror -c apt-mirror

       Or uncomment line in /etc/cron.d/apt-mirror to enable
       daily mirror updates.
[...]
CONFIGURATION EXAMPLES
       The mirror.list configuration supports many options, the
       file is well commented explinging each option.  here are
       some sample mirror configuration lines showing the various
       supported ways :

       Normal: deb http://example.com/debian stable main contrib
       non-free

       Arch Specific: ( many other arch's are supported )
       deb-powerpc http://example.com/debian stable main contrib
       non-free

       HTTP and FTP Auth or non-standard port: deb
http://user:pass@example.com:8080/debian stable main
       contrib non-free

       Source Mirroring: deb-src http://example.com/debian stable
       main contrib non-free

 Essentially what that says is that the default
 /etc/apt/mirror.list file *is* the only documentation provided
 with the package.  If the user changes it "too much", the
 documentation is lost.

 Can you provide a readme or a manpage for the configuration
 file?  Worst case: copy the default file to the examples
 directory.

 Thanks,

 Marcelo

This bug is still valid in Debian Jessie. The documentation appears to
have moved from mirror.list to /usr/bin/apt-mirror itself.
Unfortunately, the manual page still refers to /etc/apt/mirror.list as
having all the comments. They do not exist there. There is command line
help, either. Typing "apt-mirror --help" gives the error:
"apt-mirror: invalid config file specified at /usr/bin/apt-mirror line
137."

That does not help a user who has never looked at any executable files.