Totally agree. It's silly that my home lab has to cost me 5x the normal rate if I want to use some of the standard ports but that is normal now. On Fri, Feb 26, 2016 at 12:27 AM, Mark Andrews <marka@isc.org> wrote:
In message <alpine.DEB.2.02.1602260718460.11524@uplift.swm.pp.se>, Mikael Abrah amsson writes:
On Thu, 25 Feb 2016, Jared Mauch wrote:
Make sure you permit TCP/53 for DNS queries so if TC=1 lookups work.
Speaking of which, historically ISPs have been blocking TCP/135, TCP/445 and a few others towards customers (at least that's what I know). TCP/25 seems to be blocked as well.
Why isn't UDP/53 blocked towards customers? I know historically there were resolvers that used UDP/53 as source port for queries, but is this the case nowadays?
I know providers that have blocked UDP/53 towards customers as a countermeasure to the amplification attacks. As far as I heard, there were no customer complaints.
Because complaining is like talking to a brick wall most of the time. People work around the ISP idiocy by shifting ports, its easier than trying to get through help desk hell.
-- Mikael Abrahamsson email: swmike@swm.pp.se -- Mark Andrews, ISC 1 Seymour St., Dundas Valley, NSW 2117, Australia PHONE: +61 2 9871 4742 INTERNET: marka@isc.org