[nsd-users] Possible fragmentation issue transferring larger zones over IPv6?

[Darren Pilgrim]

Today I added some records to a zone and it made the AXFR size greater 
than one packet.  At that point, the zone would no longer transfer from 
my hidden master to my slaves (everything is running 4.0.1).

Normally, all of the zone transfers are done over IPv6.  The transfers 
did work when I tested them over IPv4, but I can't reliably use IPv4. 
My kludge was to break the zonefile up into several subzones, making 
each small enough to AXFR in a single packet.

I'm not sure how to document this other than showing you the "operation 
timed out: tcp" log entries and zonestatus output that shows the slaves 
are not getting the zone.

Have others run into this issue, or is this a known issue?  The relevant 
terms appear to be too common or vague for an effective search engine query.