I have wanted to know how to do this but never had the reason. My first inclination is to write a shell script in a loop. You can control the timing and save results to a file if necessary. Here's the command that seems to work

https://unix.stackexchange.com/questions/22615/how-can-i-get-my-external-ip-address-in-a-shell-script 

dig +short myip.opendns.com @resolver1.opendns.com

It seems to work. I usually check my ip using a google search. For a faster response you could find the RoBeUs dns server.
Post up your script if you write one.
Don

On 27 January 2018 at 14:46, William Park via talk <talk@gtalug.org> wrote:
Hi,

I recently switched to CarryTel, and I'm getting disconnected quite often.
So, I want to monitor my external IP, every minute.  For this, I usually
use <http://myexternalip.com/raw>, but it has rate limit.

What site do you use to get your external IP?  I want to round-robin
through these.  Google gives you this when you search "what is my ip",
but it's difficult to dig it out.  Simpler, the better.
--
William Park <opengeometry@yahoo.ca>
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