[BALUG-Admin] linuxmafia.com "retry limit exceeded"

[Rick Moen]

Quoting Rick Moen (rick@linuxmafia.com):

> Trying to figure out something in logfiles.  Filtering down this
> report just to sf-lug.com, balug.org, and savingthedolph.in DNS stuff,
> as "retry limit exceeded" seems to be a recurring theme and I'd like to 
> figure out why (and fix).

It may be utterly coincidental that all of those are sockets to port
5353 (rather than 53) on 96.86.170.229 .  Or not.  I remember that said
configuration on both of our ends was a workaround for the fsckery 
imposed on my uplink by Comcast Business, quite a while ago.  Thoughts?

Lots of searching on "refresh: retry limit for master exceeded"
suggest that error is often caused by firewalling that blocks UDP 
packets.  

I _think_ the +notcp flag on dig forces UDP, albeit that would be the
default for simple queries anyway.

$ dig @96.86.170.229 balug.org +notcp | wc -l
18
$ dig @96.86.170.229 balug.org | wc -l
18
$

But, oh hey, lookie here, when we query 5353:

$ dig -p 5353 @96.86.170.229 balug.org
;; connection timed out; no servers could be reached
$

Yeah, that would be a problem.

Right, commenting out all these in /etc/bind/named.conf.local :

        96.86.170.229 port 5353; // workaround

Checking my work.

$ grep 5353 /etc/bind/named.conf.local
        //96.86.170.229 port 5353; // workaround
        //96.86.170.229 port 5353; // workaround
        //96.86.170.229 port 5353; // workaround
        //96.86.170.229 port 5353; // workaround
        //96.86.170.229 port 5353; // workaround
        //96.86.170.229 port 5353; // workaround
        //96.86.170.229 port 5353; // workaround
        //96.86.170.229 port 5353; // workaround
        //96.86.170.229 port 5353; // workaround
        //96.86.170.229 port 5353; // workaround
$

Implementing:

linuxmafia:/etc/bind# rndc reconfig
linuxmafia:/etc/bind