Re: AW: AW: AW: AW: SSH did not work on every IP on debian x64

[Bjørn Mork <bjorn@mork.no>]

Robert Menger <rm@keyweb.de> writes:

> ah ok, thats indeed correct that CURRENTLY the rDNS is not correct, I
> have updated it shortly before, it takes, as you know, some hours
> until a DNS changing is updated worldwide.

This is not necessary given some planning ahead.  You can reduce the TTL
down to a few seconds without any real operational problem.  If you do
this more than your old TTL before the change, then you will ensure that
most caches notice your change almost immediately.  After making the
change you can of course increase the TTL again.

> And if this would be a problem, than thousands of servers wont work,
> because mostly every time the DNS record is updated during installtion
> and shortly after the installation ssh works too.

I fail to see the problem.  You can easily prepare and publish DNS data
in advance.  There is no need to change anything during or after
installation.

> And why did ssh work on any other port than port 22? (thats the weird thing in this case)
> And why did ssh work with any other IP on port 22? 

My guess would be that this is just coincidents.  You will get random
failures, but they are cached so they may seem consistent.


Bjørn