%Autojoin pattern — filter newly appearing hosts by host name and put them automatically into the specified group(s)
%Autojoin pattern
[ pattern
] [ groupname
]
This is similiar to %Autojoinbut only hosts selected by pattern matching their host name are joined.
%Autojoin pattern a.* GROUP
tells bbd to automatically put any newly appearing host with a name starting with "a" into the group 'GROUP' ("newly appearing" means that bbd is receiving status messages for a host not yet known)