On 1/23/2018 1:06 AM, Dominic Raferd wrote: > On 23 January 2018 at 04:20, Noel Jones <njo...@megan.vbhcs.org > <mailto:njo...@megan.vbhcs.org>> wrote: > > Strong spam indicators for the HELO are > (note: this is for mail coming from the internet. Authenticated > submission mail or legit mail from devices on your network might > break any of these) > - a dynamic hostname (eg. 89-73-46-234.dynamic.chello.pl > <http://89-73-46-234.dynamic.chello.pl>, which > resolves just fine) > β... > > > βIs there a method (regex?) for reliably identifying dynamic ip > addresses?β Take for instance 199-127-103-235.static.avestadns.com > <http://199-127-103-235.static.avestadns.com> - it looks dynamic to > me but it says it is static. Is it best/safest to rely on > '\.dynamic\.' occurring in the name?
There is no simple regexp, but there is the fqrdns.pcre project. The project is a large hand-maintained list of dynamic hostnames with a goal of zero false positives. It's not perfect, but it's useful and safe for general use. https://github.com/stevejenkins/hardwarefreak.com-fqrdns.pcre -- Noel Jones
