Hi, If dns.aaa.com is the master and dns.isp.com is the slave, should I config allow-transfer in named.conf of dns.aaa.com for dns.isp.com? If dns.isp.com is one of the NS records in the zone file, should I still config allow-transfer in the named.conf? IN NS dns.aaa.com. IN NS dns.isp.com. Thanks Linda