pfSense

As shown in the title, RFC2136 cache file is not properly updated. in System logs, all seems to be OK but definitely not.

php: /services_rfc2136_edit.php: phpDynDNS: updating cache file /conf/dyndns_wan_rfc2136_'test.domain.local'_ns.domain.local.cache: 111.222.333.444

(FQDN and IP was changed for privacy reasons)

/dev/ufs/pfsense0 on / (ufs, local, noatime, read-only, synchronous)
devfs on /dev (devfs, local)
/dev/ufs/cf on /cf (ufs, local, noatime, read-only, synchronous)
/dev/md0 on /tmp (ufs, local)
/dev/md1 on /var (ufs, local)
devfs on /var/dhcpd/dev (devfs, local)

As you can see, /conf is an symlink of /cf/conf but /cf is mounted as read-only.

Maybe, the cache file should be written in /tmp instead of /conf. Or /cf can be mounted as rw during update operation but is less secure than first solution.