Same issue here. The 4.3.3 release seems to be missing DDNS update functionality completely. Trying to undo the disable-nsupdate.patch and manually compiling the package fails too:
--------------------------------------- ../omapip/libomapi.a(isclib.o): In function `dhcp_dns_client_setservers': /root/swdown/dhcp/isc-dhcp-4.3.3/omapip/isclib.c:51: undefined reference to `irs_resconf_load' /root/swdown/dhcp/isc-dhcp-4.3.3/omapip/isclib.c:58: undefined reference to `irs_resconf_getnameservers' collect2: error: ld returned 1 exit status distcc[21884] ERROR: compile (null) on localhost failed Makefile:439: recipe for target 'dhclient' failed make[4]: *** [dhclient] Error 1 make[4]: Leaving directory '/root/swdown/dhcp/isc-dhcp-4.3.3/client' Makefile:580: recipe for target 'all-recursive' failed make[3]: *** [all-recursive] Error 1 make[3]: Leaving directory '/root/swdown/dhcp/isc-dhcp-4.3.3/client' Makefile:426: recipe for target 'all-recursive' failed make[2]: *** [all-recursive] Error 1 make[2]: Leaving directory '/root/swdown/dhcp/isc-dhcp-4.3.3' debian/rules:46: recipe for target 'override_dh_auto_build' failed make[1]: *** [override_dh_auto_build] Error 2 make[1]: Leaving directory '/root/swdown/dhcp/isc-dhcp-4.3.3' debian/rules:41: recipe for target 'build' failed make: *** [build] Error 2 dpkg-buildpackage: error: debian/rules build gave error exit status 2 --------------------------------------- Downgraded to 4.3.2 for now.