IXFR error

[Mark Thompson]

Hello all,
I am new to IXFR feature and I found an example for using IXFR by
Cricket Liu at http://www.acmebw.com/resources/papers/bind82.pdf.

I tried to use IXFR feature in BIND 8.2.4 (release build) and after
working for a while, I get this error message in the log file.

====
Jul 19 04:42:24 ns3 named-xfer[1277]: Unexpected serial number for
zone domain.com: 479315
Jul 19 04:42:24 ns3 named[949]: Zone "domain.com" (file
domain.com.zone): no SOA RR found
Jul 19 04:42:24 ns3 named[949]: slave zone "domain.com" (IN) rejected
due to errors (serial 479743)
====

When this happen, the database file on the slave server is completely
wrong, I have to use named-xfer to do an AXFR and restart NAMED.

Has any one experienced the same problem?

Here is my named.conf files:

On Master:

options {
        version   "Not Available";
        directory "/var/named";
        check-names master warn;                /* default. */
        datasize 20M;
        recursion No;
        pid-file "/var/named/named.pid";
        maintain-ixfr-base yes;
};

server x.x.x.x { /* our NS3 slave server */
        transfer-format many-answers;
        support-ixfr yes;
};


zone "domain.com" IN {
        type master;
        file "domain.com.zone";
        check-names fail;
        notify no;
        allow-transfer {x.x.x.x; }; /* same as the slave above */
        ixfr-base "domain.com.zone.ixfr";
};

======

On the slave:

options {
        directory "/var/named";
        check-names master warn;                /* default. */
        datasize 40M;
        recursion No;
        pid-file "/var/named/named.pid";
        maintain-ixfr-base yes;
};

server Y.Y.Y.Y { /* Master server IP */
        transfer-format many-answers;
        support-ixfr yes;
};

zone "domain.com" IN {
        type slave;
        file "domain.com.zone";
        masters {Y.Y.Y.Y; };
        ixfr-base "domain.com.zone.ixfr";
};

======

Any helps would be greatly appreciated,

TIA.