Thank you Wietse for taking the time to explain things. I really appreciate this. now all is clear.
Am Freitag, 25. Januar 2019 schrieb Wietse Venema <wie...@porcupine.org>: > Stefan Bauer: >> thank you. seems to be that >> >> if address_verify_negative_refresh_time = 30m, the next attempt to reach a >> specific recipient that is negative in cache, will still get the "old" >> answer from cache if it is not expired by >> address_verify_negative_expire_time. that is default 3d. > > I just looked things up (I wrote this code more than 10 years ago!), > and I conclude that you misunderstand the difference between > EXPIRATION time and REFRESH time. > > As long as the stored result is not expired, the stored result is > returned to smtpd. That is what expiration means. > > After the non-expired result is returned to smtpd, a refresh may > happen when the non-expired result is older than some positive > or negative refresh time. That is what refresh means. > > But it would be stupid to block the smtpd while the refresh for a > NON-EXPIRED result is in progress, because then you might just as > well have a very short expire time. > > Wietse > > >
