I'm running pfSense 2.2.6-RELEASE and have configured two DynDNS providers: no-ip.biz and nsupdate.info.
(I added the latter since no-ip.biz started nagging that I need to log in every 30 days and confirm my account – I'm planning to move to nsupdate.info altogether on the long run.)
On the Dynamic DNS status page, no-ip.biz (for which pfSense has a preset) shows me the current WAN IP in green, indicating everything is OK. The entry for nsupdate.info (Service type: Custom) shows 0.0.0.0 (in red) as the IP address, indicating registration failed.
However, when I look up the name in DNS, both come back with the correct IP, indicating both registrations worked – it's just the status info for nsupdate.info that claims something went wrong.
Settings for nsupdate.info are as provided by nsupdate.info:
Disable: not checked
Service type: Custom
Interface to monitor: WAN
Interface to send update from: WAN
Verbose logging: not checked
CURL options: none checked
Username: (DNS name to update)
Password: (host secret)
Update URL: https://ipv4.nsupdate.info/nic/update
Result Match: good|nochg
Description: nsupdate.info
For comparison, these are the settings for No-IP:
Disable: not checked
Service type: No-IP
Interface to monitor: WAN
Hostname: (DNS name to update)
MX: (blank)
Wildcards: not checked
Verbose logging: not checked
Username: (my username)
Password: (my password)
Description: (blank)
I do notice that for the Custom provider there is no hostname field, and the Hostname column on the DynDNS status page is blank for the nsupdate.info entry.
How dows pfSense determine if an update was successful? And why is the successful nsupdate.info registration reported as failed?