On 19 Feb 2014, at 8:57, Svoop wrote:
Hmmm, the problem has vanished, I can't reproduce it anymore. However,
I
keep your instructions. If the problem occurs again, I'll have the
tools in
place.
This is almost certainly due to the way bluewin.ch has set up their DNS.
Note:
bluewin.ch. 43200 IN SOA adnso1.bluewin.ch. hostmaster.bluewin.ch.
2014021801 36000 3600 1814400 300
That zone serial number probably indicates that they made changes
2014-02-18, i.e. when your trouble vanished. Their current records
include a 20-second TTL for the A to which their lowest-cost MX points,
with the 4 NS for that name handing out different records without a zone
serial number change. In short: they are violating both the DNS spec and
best practices. I don't know what they were doing when you had trouble,
but if they are playing these sorts of games now, they probably were
doing similar bad and/or wrong behavior a few days ago in a slightly
worse way that caused intermittent failures.
