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ricky_paulus_gi's avatar
ricky_paulus_gi
Icon for Nimbostratus rankNimbostratus
Mar 08, 2019

Port should be opened to allow an AXFR/IXFR

Hi everyone,

 

is there anybody know " Which port should be opened to allow an AXFR/IXFR connection to be established to a DNS listener?"

 

It would be great if you have reference link for me to read.

 

Regards, Ricky

 

application delivery
BIG-IP DNS

1 Reply

  • Rico's avatar
    Rico
    Icon for Cirrus rankCirrus
    Mar 11, 2019

    TCP port 53 from here. Zone transfers need to ensure that all the data reached its destination so that a secondary DNS server can be sure it is serving out the right records. With UDP, there would be no way to know if the zone file transfer completed properly.