By specifying

SAVE_INCOMING_HOST_LIST <host-list-file>
SAVE_INCOMING_DIR <save-dir>

in /etc/opt/openit/openit.cfg, the data files from the hosts specified
in <host-list-file> will be saved under <save-dir>. Each line in
<host-list-file> is treated as a Perl regular expression. If a host
name matches one of the reg-exps, the data files from this host will
be saved.

NOTE: The <save-dir> must be writable for the openit user, and the
directory must exist. Make sure this directory is located to a disk
with plenty of space.