Hi John, Here are the files. They are all internal zones without any references to external name servers.
VM1: ==== named.conf: ------------- # # master (on VM1) # zone "rack1.com" { type master; file "/var/named/db.rack1.com"; allow-update { key rndc-key-rack1; }; # For DHCP dynamic update }; # # slave (on VM2) # zone "rack3.com" { type slave; file "/var/named/bak.rack3.com"; masters { 10.4.3.101; }; #VM3 named IP }; zone file: /var/named/db.rack1.com ------------------------- $ORIGIN . $TTL 907200 ; 1 week 3 days 12 hours rack1.com IN SOA dnsserver1.rack1.com. admin.rack1.com. ( 8 ; serial 60 ; refresh (1 minute) 60 ; retry (1 minute) 604800 ; expire (1 week) 3600 ; minimum (1 hour) ) NS dnsserver1.rack1.com. $ORIGIN rack1.com. dnsserver1 A 10.4.1.101 $TTL 3600 ; 1 hour node1 A 10.4.1.11 TXT "007ddd47ea6ddcd890312de89e37bde496" node2 A 10.4.1.12 TXT "316a8d5e65fbd9f853df6d90ad1f24ecac" node3 A 10.4.1.13 TXT "009da8179478f9169cb47965e53d19f134" On VM2 ======= named.conf file --------------- # # Master # zone "rack3.com" { type master; file "/var/named/db.rack3.com"; allow-update { key rndc-key-rack3; }; # For DHCP update }; # # Slave # zone "rack1.com" { type slave; file "/var/named/bak.rack1.com"; masters { 10.4.1.101; }; # VM1 named IP address }; zone file: ---------- $ORIGIN . $TTL 907200 ; 1 week 3 days 12 hours rack3.com IN SOA dnsserver3.rack3.com. admin.rack3.com. ( 2 ; serial 60 ; refresh () 60 ; retry () 604800 ; expire (1 week) 3600 ; minimum (1 hour) ) NS dnsserver3.rack3.com. $ORIGIN rack3.com. dnsserver3 A 10.4.3.101 $TTL 3600 ; 1 hour node1 A 10.4.3.11 TXT "001395d7d2a164c7efde811584bbc470b9" On Fri, Feb 19, 2016 at 8:59 AM, John Miller <johnm...@brandeis.edu> wrote: > On Fri, Feb 19, 2016 at 11:45 AM, David Li <dlipub...@gmail.com> wrote: >> This is my first time to try master slave configuration. Here is a >> brief description: >> >> I have two Centos 7.1 VMs - each is configured for a zone. VM1 is the >> master for zone1 and slave for zone2. VM2 is master for zone2 and >> slave for zone1. Both zones uses DNS Dynamic Update from DHCP >> servers on the same VM >> to update the A records in their zone files. No DNSSEC configured. >> >> >> To start, everything seems to be working fine. I have one host in each >> zone and they can resolve each other fine. >> >> Now I add a new host to zone1 and its sequence number has been bumped >> up. I read that when the zone1 file changes, it will automatically >> notify its slave zone (ie. zone2) to start a zone transfer after 15 >> min. This never happened. Then I restarted named on VM2 and hoped it >> would pull the new zone1 file. This didn't happened either. >> Eventually I have to either restart the VM2 or use dig to start the >> zone transfer. >> >> Can anyone spot anything obviously wrong here? Do I need to post my >> zone file and named.conf? >> > > Hi David - > > Yes, it'd certainly help if you posted your named.conf. I don't know > that we need the whole zone file: the SOA and NS records would > probably suffice in this case, especially if the zone has tons of > records. > > I'll say: it sounds a little odd that you'd expect zone2 to be updated > when zone1 changes. The master NS for zone1 will send out NOTIFY > messages to the servers listed in the NS records for zone1; it'll also > send NOTIFYs to anything you've put in an also-notify block. > > The 15-minute wait also sounds strange: NOTIFY happens as soon as the > serial number of the master zone is incremented and the zone is > reloaded. Also, a slave NS will automatically check its master for > updates after the refresh interval (1st number after the serial) > specified in the SOA record. If you have that set to 15 minutes (900 > seconds), then yes--the slave would check its master for updates, but > it's the _slave_ reaching out to the _master_ in that case. Likewise, > slaves will reach out to their master NS when their zones are > reloaded. > > I'm not going to worry about the DHCP dynamic updates piece yet - make > sure your master and slave are set up properly before introducing > dynamic updates to the mix. > > John _______________________________________________ Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users