In message <
YwoqYcGU...@cygnus.rejectifspam.lichtech.co.uk>, at
19:26:28 on Tue, 30 May 2017, Bob Evans
<
newsab...@deleteifspam.lichtech.co.uk> remarked:
>In article <
wjGfaxRB...@perry.co.uk>, Roland Perry
><
rol...@perry.co.uk> wrote
>>>If the nameservers are set to
ns1.tsodns.com,
ns2.tsodns.com then the
>>>effective DSN zone file is the one that you can inspect and edit via
>>>the 'Custom DNS Records' button (on LHS).
>>
>>Sorry, but that's precisely what *isn't* a mirror of the actual DNS
>>settings. It's where I was when I placed the first of my four call to
>>them.
>>
>>The information there is merely some kind of "wish list", which is not
>>fully posted/updated to the DNS server 'warts and all'.
>
>That seems very weird (and annoying). On behalf of customers, I manage
>more than 100 domains at TSOhost with zone files pointing to a mixture
>of TSO dedicated servers and cloud server instances and have never
>encountered such a problem. I must lead a charmed life.
It would of course help if the TSO Custom DNS page said, to a proposed
update "nah, I don't want to do that". Or even "I tried, and it
wouldn't". Or even even "I tried, and this is now what it's set to, and
if that wasn't what you just asked for, then panic".
At least one could then investigate, even if it declined to say what
precise part of the proposed update was causing it indigestion.
>One thought: If making DNS alterations to a domain that is already in
>use, do you remember to wind down the TTL values on the affected
>records well in advance of making the intended changes?
That's a very outdated meme. In my case I was making the very first
changes to a domain that was in some sense 'parked'. But it also
involved switching to new DNS servers (the custom vs cpanel ones).
When requesting DNS, the only thing which causes a delay to kick in is
if someone else using the same ISP-DNS-server has caused the information
to be cached. If it's never been cached there, then the cache hasn't
been primed and the TTL hasn't yet kicked in.
>My experience is that the delay between making a change in the web
>control panel and the resulting update of the "real" zone file is a
>matter of seconds or a few minutes at most.
Only if the TSO system doesn't say "nah".
>But if the old DNS data is cached (with the typical default TTL of 24
>hours) all over the place outside of TSO, then naturally it can take
>quite a while for the outside world to catch up.
But a 'parked' domain isn't likely to be widely cached like that,
because no-one has any cause to browse it (or in my case send it any
email).
The DNS changes which enabled my 3rd party web hosting (which TSO said
probably quite correctly - in view of my own inability to - only *their*
techies could handcraft past their "nah-gatekeeper") took a while to
propagate via my wired broadband supplier, because I'd previously tried
browsing to the site, and got the stale[1] cached answer.
But switching to a completely unrelated mobile phone data connection,
with no cache yet primed for my domain, the intended result came up
immediately.
Similarly, using various third party DNS looking glasses, you wouldn't
expect them to have had their cache primed.
[1] MX 86400 which is 24hrs, but for no reason they care to explain, the
CNAME and A records they set by hand for me 3600 - an hour.
--
Roland Perry