Using a plain smarthost config, sendmail fails sending mail with:
# sendmail -v -q
Running /var/spool/mqueue/j29Juv2T031315 (sequence 1 of 4)
getmxrr: res_search (mail.corp.redhat.com) failed with impossible
Operating system error
Downgrading to 8.13.2-1 fixes it.
*** This bug has been marked as a duplicate of 150288 ***
Changed to 'CLOSED' state since 'RESOLVED' has been deprecated.