Feature #2148

Dynamic DNS Update Frequency

Added by Chris Mirchandani almost 9 years ago. Updated over 8 years ago.

Dynamic DNS
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The current Dynamic DNS configuration does not check for IP address changes often enough to be useful in many situations. I believe the script /etc/rc.dyndns.update is responsible for checking for a changed IP and updating the Dynamic DNS system. However, it is run via cron and the cron is set to update at 1:01 AM, see below.

1  1  *  *  *  root /usr/bin/nice -n20 /etc/rc.dyndns.update

A potential fix would be to have an option on the Dynamic DNS page that allows the user to see the default setting and update it if necessary.

A Modification that resolves this issue.

*/3  *  *  *  *  root /usr/bin/nice -n20 /etc/rc.dyndns.update

I have listed this as an AMD64 architecture issue because I only run AMD64, but I believe this issue is present in the other architectures as well. I also listed this as 2.0.1 issue because there is no option to select 2.0 and 2.0.1 like an all 2.x all option, but I know the issue exists in 2.0 AMD64.


#1 Updated by Chris Buechler almost 9 years ago

  • Status changed from New to Rejected

It updates on every IP change, the cron job is only to update if the IP hasn't changed in 25 days so the provider doesn't expire your hostname.

#2 Updated by Chris Mirchandani almost 9 years ago


Updates may take place if the IP on the WAN interface changes, but not if the pfSense device is behind a DSL or Cable router. When the public IP changes, the Dynamic DNS page shows the cached IP in red indicating that it knows the cashed IP is not the current public IP and that is has not updated the Dynamic DNS host with the current public IP. However, it does not update the Dynamic DNS host until 1:01 AM unless you change the cron time like in my example or if you edit the Dynamic DNS entry and save it even without making changes.

#3 Updated by Chris Buechler almost 9 years ago

You can change your cron job in that case. We're not going to run something every 3 minutes on everyone's system that only a minuscule fraction of a percent of users actually need.

#4 Updated by Chris Mirchandani almost 9 years ago


My suggestion is not to change the time it runs for everyone. My suggestion is to show the time/frequency it runs on the Dynamic DNS page and provide an option to change this value.

#5 Updated by Chris Buechler almost 9 years ago

  • Status changed from Rejected to Closed

the cron package allows editing that easily, don't think it's worthwhile for us to bother otherwise. though if you're up for implementing it, make a merge request in git. I'd be fine with merging it.

#6 Updated by themisa themisa over 8 years ago

I've yet to see it update on WAN IP change.
My WAN_DSL ip has changed, the dsl modem is connected directly to PF.
DynDNS IP is in red, still outdated.

Is it a bug or is there an additional setting i forgot to check?

#7 Updated by themisa themisa over 8 years ago

I've been able to reproduce it.
When i open WAN_DSL connection and apply changes it does force a DynDNS update.

However, if i unplug the DSL modem, then plug it back in, WAN_DSL ip changes
on Dashboard > Interfaces > WAN_DSL but DynDNS update isn't triggered.

How can we get this fixed?

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