[tecoripa]

Problem solved.

I rolled up my sleeves, set up my ssh key, and logged into the router to peer under the hood.

After some investigation and tests, I found that the ddns updater script was rejecting my public WAN IP, which was assigned by AT&T from the 172.8.xxx.xxx range.

Line 588 of /usr/lib/ddns/dynamic_dns_updater.sh had a filter to exclude private IP subnets:

[ $use_ipv6 -eq 0 ] && __IP=$(echo $1 | grep -v -E "(^0|^10\.|^127|^172|^192)") # no private IPv4's

But only a portion of the 172. and 192. ranges are private: 172.16.0.0/12 (172.16.0.0 – 172.31.255.225) and 192.16.0.0./16 (192.168.0.0 – 192.168.255.255): https://www.arin.net/knowledge/address_filters.html

I updated the filter to only exclude IPs in those ranges (changed line 588, and added a line):
[ $use_ipv6 -eq 0 ] && __IP=$(echo $1 | grep -v -E "(^0|^10\.|^127|^192\.168)") # no private IPv4's
[ $use_ipv6 -eq 0 ] && __IP=$(echo $1 | grep -v -E “^172\.(1[6-9]|2[0-9]|3[0-1])\.”) # no private 172.16.0.0/12 IPv4s`

After that, I was able to set and save and confirm my Dynamic DNS updater settings in the pcwrt interface.

Unfortunately, however, this change I made will be wiped out next time I update the OS, unless it’s folded into the pcwrt codebase. Can you open this up as a bug, and apply the fix with the next release of the OS?

FWIW, the latest version of this script in the openwrt github repo correctly filters private address spaces:

https://github.com/openwrt/packages/blob/master/net/ddns-scripts/files/dynamic_dns_functions.sh#L852

[tecoripa]

I tried disabling parental control entirely, and got the same result when I went to update Dynamic DNS: Failed to update Dynamic DNS, please check your network connection. I rebooted the router and tried it again, just to make sure, to no avail.

[tecoripa]

OK, I’ll give that a try tonight.

[tecoripa]

So I was able to get my AT&T router set up as a bridge, and the pcwrt router now responds to the public WAN dynamic IP address, so that’s all good.

The final piece that I’m struggling with is Dynamic DNS: whenever I try to set up the OpenDNS Home configuration, as listed in the five steps in this forum post:

How to set up OpenDNS

… I run into a similar problem others have had. I get this error message on the router when I try to save and enable my Dynamic DNS settings on the router:

Failed to update Dynamic DNS, please check your network connection

When I go to the following test API URL, substituting my credentials and IP in the URL,

https://[USERNAME]:[PASSWORD]@updates.dnsomatic.com/nic/update?hostname=all.dnsomatic.com&myip=%5BWAN IP Address]

I get back a successful response:

good [MY WAN IP ADDRESS]

I’ve double and triple-checked that my credentials are correct in the settings. The test dnsomatic URL correctly updates the OpenDNS and Google Domains services (it shows the updates in the activity logs), so I’m thinking the problem must be on the router, or somewhere between the router and dnsomatic.

• This reply was modified 7 years, 1 month ago by tecoripa.

[tecoripa]

Yes, that worked as I expected. Thank you.

[tecoripa]

Thank you.

For A) I’ll give it a try; I had some issues setting it up when I first got the router, but I’m more familiar with it now, and will look at setting up Dynamic DNS again.

For B), the Pace 5031NV router has quite a bit of a different user interface, and I’m not sure about IP passthrough being an option, although it does have some DMZ forwarding settings that others have had some luck with. I’ll take a look again tonight, and report back.

[tecoripa]

Thank you. I’ll give that a try.

[tecoripa]

After contacting support, they suggested that the problem might be caused by cached content in the browser from before the firmware update. I cleared my browser cache, and all the settings reappeared, fresh from the router. Case closed.

[Author]

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