I was updating my network to use a different subnet and realized that the last time I did that, my HP printer stopped working because a lot of the network drivers set the IP address into the printer settings.
So I figured that maybe I would need to update the printer’s IP address on my Mac. I looked at the printer settings and didn’t see anything that might work.
Once again resorted to Google and after a search for “change IP address for a Mac printer”, I found a post in the Apple forums about how to fix this using CUPS (https://discussions.apple.com/message/4910263#4910263)
Now I know a lot of sys admins use CUPS to manage printers in the enterprise, and it’s a fairly full featured open source system (developed by Apple as it turns out) for using network devices, so I did a quick connection to the URL suggested (http://127.0.0.1:631/printers).
Not surprisingly, I got an error message that told me that the web interface wasn’t enabled:
So following the instructions, I went to the terminal and ran:
sudo cupsctl WebInterface=yes
And then the page displayed with my printer information on it:
From there I was able to navigate to the printer settings (very normal web application, click the links, choose some drop downs, etc). Where I eventually discovered that my printer is actually using a lookup to figure out how to connect to the printer, so no changes were actually necessary:
And then since I figure this web interface was turned off for a good reason, I shut it back down:
sudo cupsctl WebInterface=no