Acceptable to poll https://ipv4.tunnelbroker.net/ipv4_end.php ?

[kfu]

I have an ostensibly dynamic IPv4 address from Comcast, but it doesn't change all that often. Still, if/when it does change, I'd like the tunnel to react with the quickness.

I have a script that will fetch https://ipv4.tunnelbroker.net/ipv4_end.php?ipv4address=AUTO&; plus all of the various identification/authentication values. A single machine does this from behind the AirPort Extreme that's configured to perform the tunneling duties.

Currently, it replies "That IPv4 endpoint is already in use."

Can I set up a cron job to run this hourly? Can I assume that it will do the right thing if/when our address changes?

[cholzhauer]

You can have cron do anything you want...if you want it to run every hour, have at it.

Currently, it replies "That IPv4 endpoint is already in use."

You'll have to devise a way to handle that "condition" in your script.

[kfu]

You can have cron do anything you want...if you want it to run every hour, have at it.

Thanks. I just didn't want to be perceived as abusive.

Currently, it replies "That IPv4 endpoint is already in use."

You'll have to devise a way to handle that "condition" in your script.

Oh, I don't expect that it really needs handling... :)

[cholzhauer]

I don't think they would consider it "Abusive" but I guess you could email ipv6@he.net to double check.

[keithfernie]

If this was considered abusive you should change your script to detect a change in the dynamic IP first then connect to Hurricane Electric only when there was a new dynamic ip. If you was using a similar script with a dynamic dns provider instead you usually would be required to do this.
When testing your script for a change in dynamic IP address, try switching your Airport Extreme off then back on. This may force a change in the dynamic ip, mine changes when I switch my router off then back on.

[snarked]

I agree.  It woud be better for you to run the HE web page script only when detecting a change in the assigned IPv4 endpoint address.  Your hourly-run script "remembers" the IP address detected from the last run (by storing it in a file) and compares the value to the current value.  Only when different should it call the HE web page script and write the new value locally to its file.

[kfu]

Well, the nice thing about ipv4addr=AUTO is that I don't have to know what the address is. I'm doing this from behind the NAT, so if I have to discover what the outside address is and track changes, well, that's a lot more work.

I'm willing to do that work if required, but I'd rather not. Not because I'm lazy, but because it's just more reliable to not have to. But, as is the case with dynamic DNS, it's considered abusive to poll for updates redundantly, then I'll do it.

I was just hoping to get an official response.