OPNsense Forum

English Forums => 26.1 Series => Topic started by: bugacha on March 14, 2026, 10:08:27 AM

Title: OPNSense setting wrong address with native ddclient to 104.18.0.0
Post by: bugacha on March 14, 2026, 10:08:27 AM
Mirroring Reddit thread here - https://www.reddit.com/r/opnsense/comments/1rmqih8/opnsense_setting_wrong_address_with_native/


Since maybe 1-2 weeks ago (upgraded to 26.1.3) by DDNS client suddenly changed my external IP to 104.18.0.0

I've used cloudflare-ipv4 "Check ip method"

104.18.0.0 - belongs to Cloudflare

Switching to Akamai fixes the problem
Title: Re: OPNSense setting wrong address with native ddclient to 104.18.0.0
Post by: NeoV00 on March 17, 2026, 03:18:36 PM
Hi,

we've been experiencing the same issue for a few days now on multiple firewalls running the latest firmware. Switching to "icanhazip" didn't resolve the problem. I'm going to give Akamai a try

Does anyone have an idea what might be causing this?
Title: Re: OPNSense setting wrong address with native ddclient to 104.18.0.0
Post by: davidolrik on March 18, 2026, 01:39:43 PM
Quote from: NeoV00 on March 17, 2026, 03:18:36 PMDoes anyone have an idea what might be causing this?

The Cloudflare endpoint https://1.1.1.1/cdn-cgi/trace is broken.

Switching to akamai-ipv4 works for me as a workaround.
Title: Re: OPNSense setting wrong address with native ddclient to 104.18.0.0
Post by: franco on March 18, 2026, 02:15:17 PM
FWIW, opening https://1.1.1.1/cdn-cgi/trace shows my correct IPv4.


Cheers,
Franco
Title: Re: OPNSense setting wrong address with native ddclient to 104.18.0.0
Post by: sopex8260 on March 18, 2026, 02:20:15 PM
I also get 104.18.0.0 at https://1.1.1.1/cdn-cgi/trace

Not using opnsense
Title: Re: OPNSense setting wrong address with native ddclient to 104.18.0.0
Post by: Flachzange on March 20, 2026, 08:19:00 PM
Oh, thanks it's not only me...

This drives me crazy since a week or so. Without updated DNS I am locked out of my home network. In my case, I regulary update
- IPv4 of sub1.domain.com
- IPv6 of sub1.domain.com
- IPv4 of sub2.domain.com

I thought it was somehow related to having three entries and tried to isolate it to one of them, but no success.

The weird part is:

- sometimes it works
- OPNsense even adopts the wrong IP, i.e. cloudflare is confirming 104.18.0.0 back to OPNsense. But only once the correct was updated to cloudflare.

I updated the IP once via the API call directly (outside OPNsense) that seem to have worked, but maybe it was just coincidence

Edit: Understood, the "check ip method" used cloudflare to determine the ip address and that thing is broken
Title: Re: OPNSense setting wrong address with native ddclient to 104.18.0.0
Post by: Monviech (Cedrik) on March 20, 2026, 10:02:17 PM
Same happened to me, thanks for posting about this.

I chose akamai now and things work again.