I'm learning Eric Allmann's sendmail since 25 years
now and so far haven't stopped doing this. There isn't a year I'm
not learning something new about sendmail.
Today was a day to revisit sendmail's (optional) way of caching
the last dialogue with other mailhosts, the hoststat
option. Things re-learned:
# sendmail -bh (aka hoststat)
# sendmail -bH (aka purgestat)
# sendmail -O Timeout.hoststatus=1s -v -q
(Research done on the decsystem running ultrix-4.4 and a fairly
current sendail-18.4.x, having the op.me handy.)