Limiting the total number of simultaneous outbound zone transfers

With some name server implementations, you can limit the total number of simultaneous zone transfer requests that are served. Setting this number too low can have adverse affects on ADNR's ability to communicate with the name server. When setting this limit, take into account the number of secondary name servers that use this name server as the master name server for their zones, as well as the number of ADNR-managed zones that are configured under this name server. During ADNR initialization and after a MODIFY REFRESH command, ADNR requests simultaneous zone transfer requests for each zone it manages. Consider the number of zones configured under the same dns statement when you are setting zone transfer limits in the name server.

For the BIND 9 name server, the total number of simultaneous outbound zone transfers allowed is specified on the transfers-out option.