Secondary Server and Firewall??

[Albert Kasper]

Hi,

I've got a primary Nameserver (bind) and a secondary nameserver (NT).
I want to propagate changes to the secondary nameserver, and change requests
are sent to the secondary nameserver (at least they are written into the
log).
However, the information is never replicated. I suspect the firewall to be
the victim, but how? Ports 53 and 123 are open both for UDP and TCP. Does a
secondary nameserver need any special ports?