Categories / Networking
Miscellaneous System Administration Notes
Some miscellaneous notes I may split out into separate posts later… don’t bookmark this one.
View open network connections on OS X
sudo lsof -lnP +M -i4
The options:
-l don't convert uids to login
-n dont' convert network numbers to to hostnames
-P don't convert port numbers to service names
+M enable portmapping
-i4 look for IPv4 connections
See also nettop. 3rd party apps include Little Snitch and RubberNet.
Perl SSL Debugging
I just spent about 3 hours trying to figure out why a Mojolicious daemon wasn’t permitting SSL connections. Here’s what I checked:
- the server was accessible (
iptables, routing, etc.) - the port was accessible (I could set mojo’s
listentohttp://*:443) and it would respond fine on my laptop - the entire
/usr/localhierarchy,/etcand/home/scottwere identical to my development environment (save the machine specific differences) and had the same permissions and ownership.
So basically at this point I narrowed it down to SSL. Something in the SSL setup wasn’t correct.