Hi, > > >These aren't new netblocks for us from them, but it seems awfully weird > >that we would be operating on these IPs for 2+ years then all of the > sudden > >have them listed like they're dialup IPs. > > generic/dialup DNS names can help here. If they aren't dynamically > allocated, their DNS records should contain at least string "static". > > It's generally advised to use personalized DNS names (reverse and direct) > for mailservers or any hosts supposed to send e-mail. > > Note that if you send mail using authentication, you usually don't need > this. >
These are bare metal servers dedicated to us in their datacenter. They control reverse DNS, but we have given them the hostnames we have explicitly defined for this, and to match our forward DNS. > >I don't know if that's just a boilerplate message or it actually refers to > >the precise reason why my IPs were added to the PBL. > > yes, they are explicitly telling you to use mailserver outside of this > range. > If you have own mailserver, you should dedicate IP address for it, one > that > won't be added to PBL by your ISP. > Our DNS entries and the way we operate our mail server (primarily relaying scanned mail to M365 systems) hasn't changed in the two years we've been with this provider. So you believe these IPs would have been added to the PBL by our ISP? Do you know how that might have been done? I'm trying to understand why or how we would have been added to the PBL when nothing was changed. It was the entirety of our netblocks, not even just the IPs we're currently using. Thanks so much for your help.
