$ ./extract-ip.rb s1-pinglogs-2016-10-19_17-25-51/
192.168.11.146 ec:f4:bb:41:00:a1
192.168.11.160 ec:f4:bb:41:01:fc
192.168.11.72 4c:cc:6a:58:c4:01
192.168.11.156 ec:f4:bb:41:00:a1
192.168.11.229 ec:f4:bb:41:00:44
192.168.11.202 ec:f4:bb:41:00:e5
192.168.11.164 54:ee:75:54:a3:1f
192.168.11.193 ec:f4:bb:41:01:6c
192.168.11.138 ec:f4:bb:41:01:5e
192.168.11.217 ec:f4:bb:41:00:e9
192.168.11.161 08:00:27:27:06:d4
192.168.11.252 ec:f4:bb:41:00:82
192.168.11.185 ec:f4:bb:41:00:b1
192.168.11.1 00:1b:21:48:23:ce
192.168.11.170 3c:97:0e:e5:db:83
192.168.11.144 ec:f4:bb:41:01:2c
192.168.11.130 3c:97:0e:e5:db:61
192.168.11.73 4c:cc:6a:58:c4:08
192.168.11.71 4c:cc:6a:58:c4:19
192.168.11.241 3c:97:0e:99:b6:ed
192.168.11.132 ec:f4:bb:41:00:ee
192.168.11.247 54:ee:75:54:a4:b4
192.168.11.70 90:2b:34:11:24:92
192.168.11.60 3c:97:0e:99:b7:e2
192.168.11.74 4c:cc:6a:58:c4:05
192.168.11.68 34:40:b5:db:10:f8
192.168.11.162 3c:97:0e:99:b4:fe