LinuxQuestions.org - [SOLVED] DDNS on Centos

- Linux - Server (https://www.linuxquestions.org/questions/linux-server-73/)

- - DDNS on Centos (https://www.linuxquestions.org/questions/linux-server-73/ddns-on-centos-928531/)

i'm trying to configure ddns on centos, but it doesn't work.
i have a machine named centos.domain.com that i've installed dhcp and bind on it.also i have two other machine, centos2.domain.org and bt.domain.org.

here's my configuration files :
/etc/dhcpd.conf:

Code:

ddns-update-style interim;

ignore client-updates;

ddns-domainname "domain.org";

include "/etc/rndc.key";

zone domain.org. {

primary 127.0.0.1;

key rndckey;

}



subnet 10.1.1.0 netmask 255.255.255.0 {



# --- default gateway

        option routers                        10.1.1.10;

        option subnet-mask                255.255.255.0;



#        option nis-domain                "domain.org";

        option domain-name                "domain.org";

        option domain-name-servers        10.1.1.10;



        option time-offset                -18000;        # Eastern Standard Time

#        option ntp-servers                192.168.1.1;

#        option netbios-name-servers        192.168.1.1;

# --- Selects point-to-point node (default is hybrid). Don't change this unless

# -- you understand Netbios very well

#        option netbios-node-type 2;



        range dynamic-bootp  10.1.1.12 10.1.1.16;

        default-lease-time 21600;

        max-lease-time 43200;



        host bt {

        hardware ethernet 00:0c:29:a9:cd:96;

        fixed-address 10.1.1.13;

        }



}

/etc/named.conf :

Code:

// Red Hat BIND Configuration Tool

// 

// Default initial "Caching Only" name server configuration

//



options {

        directory "/var/named";

        dump-file "/var/named/data/cache_dump.db";

        statistics-file "/var/named/data/named_stats.txt";

        /*

        * If there is a firewall between you and nameservers you want

        * to talk to, you might need to uncomment the query-source

        * directive below.  Previous versions of BIND always asked

        * questions using port 53, but BIND 8.1 uses an unprivileged

        * port by default.

        */

        // query-source address * port 53;

};



zone "." IN {

        type hint;

        file "named.root";

};



zone "localdomain." IN {

        type master;

        file "localdomain.zone";

        allow-update { none; };

};



zone "localhost." IN {

        type master;

        file "localhost.zone";

        allow-update { none; };

};



zone "0.0.127.in-addr.arpa." IN {

        type master;

        file "named.local";

        allow-update { none; };

};



zone "0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa." IN {

        type master;

        file "named.ip6.local";

        allow-update { none; };

};



zone "255.in-addr.arpa." IN {

        type master;

        file "named.broadcast";

        allow-update { none; };

};



zone "0.in-addr.arpa." IN {

        type master;

        file "named.zero";

        allow-update { none; };

};



zone "domain.org" {

type master ;

file "db.domain.org";

allow-update {key "rndckey";};

notify yes;

};



include "/etc/rndc.key";

what's wrong, guys ?

Quote:

ignore client-updates

.. this might be a problem for a start, have you read 'man 5 dhcpd.conf'?

i'm configuring it based on this page:
http://www.techienote.com/2010/06/dy...on-centos.html

It won't affect the registration unless the host belongs to a different domain than that hosted by the dns server... there should be something in the logs .. ?

when i issue tail -f /var/log/messages i don't see nothing but this :

Code:

Feb 10 10:40:17 centos dhcpd: Dynamic and static leases present for 10.1.1.13.

Feb 10 10:40:17 centos dhcpd: Remove host declaration bt or remove 10.1.1.13

Feb 10 10:40:17 centos dhcpd: from the dynamic address pool for 10.1.1/24

Feb 10 10:40:17 centos dhcpd: DHCPREQUEST for 10.1.1.13 from 00:0c:29:a9:cd:96 via eth1

Feb 10 10:40:17 centos dhcpd: DHCPACK on 10.1.1.13 to 00:0c:29:a9:cd:96 via eth1

looks like ddns is not enable or something !

also i'm getting this error

Code:

 grep named /var/log/messages

Feb 10 12:10:11 centos named[12371]: client 10.1.1.10#44061: updating zone 'domain.org/IN': update unsuccessful: bt.domain.org: 'name not in use' prerequisite not satisfied (YXDOMAIN)

Feb 10 12:13:03 centos named[12744]: client 10.1.1.10#55044: updating zone 'domain.org/IN': update unsuccessful: bt.domain.org/TXT: 'RRset exists (value dependent)' prerequisite not satisfied (NXRRSET)

i solved the problem.apparently when you register a record in named, manually, you can't update it with ddns.so i deleted the entries from zone database(in my case /var/named/db.domain.org) and now dhcp can update dns records.
but i have a question.when the client's record is updated, i can't see the entry in my zone for like a quit time.it seems there is a file with jnl extention in /var/named with same name as my zone database.what's the role of this file ?

That would be a journal .. see: http://www.zytrax.com/books/dns/ch7/xfer.html

thank you kbp.but i didn't undrestand the role of jornal file ?!?!

Quote:

Journal files are used by Dynamic DNS (DDNS) when modifying the master and when receiving IXFR changes on slave zones. The journal file is in binary format and its name is formed by appending the extension .jnl to the name of the corresponding zone file.

All changes made to a zone using dynamic update are written to the zone's journal file. The server will periodically flush the complete contents of the updated zone to its zone file this happens approximately every 15 minutes. When a server is restarted after a shutdown or crash, it will replay the journal file to incorporate into the zone any updates that took place after the last zone file update.

.. is this explanation ok ?