Subj : Re: DNS Nodelist available for fsxnet
To : deon
From : Zip
Date : Sat Nov 11 2023 03:25 pm
Hello Deon!
Thank you for your reply!
On 11 Nov 2023, deon said the following...
de> Although you have mentioned server 83.255.255.1, I actually have an IP
de> block on 83.255.224.0/24 (perhaps 255.1 uses?). When I enabled the DNS
de> queries, several servers in this block were hammering clrghouz - 10+
de> queries a second, and to the same records (so not honouring the TTL).
Yep! That netblock belongs to Tele2, one of the major ISPs here in Sweden (who in recent years acquired a company called ComHem, one of the major players in residential broadband here).
de> The TTL (negative) cache time might actually be my problem - I may not be
de> returning the right response for an NXDOMAIN, its something I need to
de> double check on to be sure (I think I need to included an SOA record in
de> the authority record of the response), which I'm not doing.
Negative TTLs are a pain, and DNS troubleshooting can be, too! :)
de> I'll disabled that block for now - let me know if it works for you.
Thanks! It seems that this changed things a little -- querying 83.255.255.1 or 83.255.255.2 multiple times in a row now returns either SERVFAIL or a correct answer in an alternating fashion, e.g.:
