Posts Tagged ‘vpn’

Accessing Free Guangzhou Airport Wi-Fi on MacBook Pro

Saturday, December 2nd, 2017

Guangzhou airport has a crazy way of providing free wifi. If you have a Chinese phone you can receive a login account via text, but if you don’t have a Chinese number, then you have to go to a physical ticket machine, scan your passport, and quickly jot down (or photograph) the code that flashes on the screen for 15 seconds.

Once you have this code, you have to click “Ticket Cert” on the login page and enter the info.

This worked fine for me on my iPhone.

But when I tried to follow the same steps on my laptop, the “Ticket Cert” option did not appear on my browser login prompt. I saw a slightly different page that only had the SMS option (and a bunch of half-loaded CSS and javascript errors).

I tried many things including spoofing the UserAgent on my browser. Nothing seemed to work.

Finally, I changed the MAC address on my laptop to match my already-online iphone’s

ifconfig en0 ether [iphone's "Wi-Fi Address"]

This worked.

PS: So far, I have not managed to get any sort of vpn, proxy or ssh tunnelling to work.

EZproxy bookmarklet

Friday, March 20th, 2015

The columbia proxy/vpn never worked super well for me. Or at least I didn’t try very hard to set it up. I really only need it for viewing academic articles off campus. So usually I just search for it via the columbia library’s website, log in, and retrieve the article. Doing this I noticed that the library is just feeding me the usual link (e.g. from acm dl) but via an “ezproxy”. So

http://dl.acm.org/citation.cfm?id=2185544 becomes

http://dl.acm.org.ezproxy.cul.columbia.edu/citation.cfm?id=2185544.

I wrapped this replacement into a javascript bookmarklet.

javascript:(function(){window.location.href=window.location.href.replace(/http:\/\/[^\/]*/,"$&.ezproxy.cul.columbia.edu");})()

Now I can follow the google search result, hit this bookmarklet, log in if I haven’t already, and view the articles.

Mac OS X 10.6 VPN configuration error after wrong password

Wednesday, April 27th, 2011

The built-in VPN client in mac os x 10.6 annoyingly won’t remember passwords. I have to type it in every time I connect. What’s worse is that if I mistype it some how ruins the VPN client so that I can reconnect. When I try I don’t even make it to the password prompt. I just get:


A configuration error occured. Verify your settings and try reconnecting

I manage to restart the VPN client by issuing this in a Terminal:


sudo launchctl stop com.apple.racoon
sudo launchctl start com.apple.racoon

After that when I try, I get to the password prompt and I’m able to reconnect.

Similar idea here

Mac OS X Snow Leopard VPN stops working

Monday, April 18th, 2011

All of a sudden my VPN client (the one built into Mac OS X 10.6) asked me for my password. I’d already been logged into the NYU VPN for a few hours. I accidentally clicked cancel.
I tried to reconnect, but now I kept getting this error:


A configuration error occurred. Verify your settings and try reconnecting.

The little icon in the corner would spin and read “Connecting…” but this error would pop up even before it prompted me for my username and password.

So in true Mac style I spent 20 minutes trying to figure out how I could fix this without restarting. (I’m sure restarting would have worked just fine).

Turns out VPN couldn’t connect because another similar process was (already) running. By opening up Terminal.app I issued:


ps -ef | grep racoon

and saw:


    0 84139     1   0   0:00.06 ??         0:00.13 /usr/sbin/racoon

Then I issued:


sudo kill 84139

I reconnected VPN and all is well.