Automatic refresh secondary when primary change

[Sim]

Hi!

When I change serial for domain in primary server, and reload it,
secondary update immediately its file, but don't reload it.

I need to wait or reload secodary manually.

This is an example:


===== Master =====

        zone "xxx.net" in {
                type master;
                file "master/xxx.net";
                allow-transfer { x.x.x.2; };      <- Secondary
        };

----------------------------------

$TTL 33600
@               IN      SOA     ns1.xxx.net. postmaster.xxx.net. (
                                2006020102      ;SERIAL
                                7200            ;SOA REFRESH
                                6500            ;SOA RETRY
                                1209600         ;SOA EXPIRE
                                3600 )          ;SOA MINIMUM TTL
;
                        NS      ns1.xxx.net.
                        NS      ns2.xxx.net.
;
www                     A       1.2.3.4



===== Slave =====

        zone "xxx.net" in {
                type slave;
                file "slave/passepartout.net";
                masters { x.x.x.1; };        <- Primary
        };


Can secondary force refresh/reload in this case?

Thanks!