My recollection is that something was eating the TXT results; but not the A records.
Probably a PIX or something like that, it broke ESMTP pretty badly too. > On Nov 24, 2017, at 06:34, RW <rwmailli...@googlemail.com> wrote: > > On Thu, 23 Nov 2017 16:39:25 -0700 > Dave Warren wrote: > >>> On 2017-11-21 11:57, RW wrote: >>> On Tue, 21 Nov 2017 08:55:34 -0600 >>> David Jones wrote: >>> >>> >>>> You are correct. I haven't dug into the code to verify but it >>>> appears that 3.4.x sa-update does use the DNS TXT record to know >>>> when to download so it doesn't hurt anything to run this version >>>> hourly. >>> >>> >>> By the sound of it this warning doesn't apply at all to anyone with >>> a normal up to date installation. >>> >> >> It mostly shouldn't, but when I was supporting a mail server that >> included a SpamAssassin integration, we ran into a non-zero number of >> installations where DNS checks failed and they fell back on direct >> connections. > > I don't follow that. sa-update needs the result of the dns lookup to > construct the download URL.