I setup a server with ssh listening only on an IPv4 address. I setup an identical server with ssh listening only on an IPv6 address. These are hosts with no public DNS, no fully qualified domain names, not advertised anywhere, simply running ssh on an IP address.

IPv4

The IPv4 host in February 2016 so far:

bzcat auth.log* | grep Invalid | cut -d" " -f7-12 | sort | uniq -c | sort -n | wc -l

240

This shows the host listening on an IPv4 address has seen 240 attempts to login with various usernames over ssh.

IPv6

The IPv6 host in February 2016 so far:

bzcat auth.log* | grep Invalid | cut -d" " -f7-12 | sort | uniq -c | sort -n | wc -l

0

This shows the host listening on IPv6 only has seen zero attempts at ssh.

IPv4 SSH Attempts

The details from the IPv4 host:

1 Invalid user from 177.8.225.130
1 Invalid user .php from 54.152.237.130
1 Invalid user 125215612612fasf from 37.187.120.18
1 Invalid user 4124151261616151 from 37.187.120.18
1 Invalid user Bobo from 60.173.14.5
1 Invalid user Fake from 185.130.5.179
1 Invalid user a from 181.112.229.30
1 Invalid user a from 47.89.30.90
1 Invalid user account from 180.97.81.197
1 Invalid user admin from 103.12.119.23
1 Invalid user admin from 119.164.254.57
1 Invalid user admin from 125.212.232.7
1 Invalid user admin from 185.110.132.54
1 Invalid user admin from 187.5.121.246
1 Invalid user admin from 188.227.174.163
1 Invalid user admin from 188.244.208.30
1 Invalid user admin from 52.34.171.0
1 Invalid user admin from 52.91.143.180
1 Invalid user admin from 58.214.233.179
1 Invalid user admin from 74.208.162.27
1 Invalid user admin from 78.25.16.22
1 Invalid user admln from 46.148.20.35
1 Invalid user apache from 58.214.233.179
1 Invalid user bananapi from 89.163.148.90
1 Invalid user ben from 85.69.155.61
1 Invalid user bence from 85.69.155.61
1 Invalid user benjamin from 85.69.155.61
1 Invalid user benji from 85.69.155.61
1 Invalid user benoit from 85.69.155.61
1 Invalid user bettina from 85.69.155.61
1 Invalid user bianca from 85.69.155.61
1 Invalid user boris from 85.69.155.61
1 Invalid user bridget from 85.69.155.61
1 Invalid user bruce from 85.69.155.61
1 Invalid user bruno from 85.69.155.61
1 Invalid user bryan from 85.69.155.61
1 Invalid user byte from 83.169.18.20
1 Invalid user carina from 85.69.155.61
1 Invalid user caro from 85.69.155.61
1 Invalid user carolin from 85.69.155.61
1 Invalid user caroline from 85.69.155.61
1 Invalid user carsten from 85.69.155.61
1 Invalid user caterina from 85.69.155.61
1 Invalid user catherine from 85.69.155.61
1 Invalid user data from 23.105.14.204
1 Invalid user dup from 175.136.242.41
1 Invalid user fa12512125125125 from 37.187.120.18
1 Invalid user git from 128.199.50.75
1 Invalid user jenkins from 128.199.50.75
1 Invalid user jose from 58.214.233.179
1 Invalid user kopet from 46.148.20.35
1 Invalid user lewman from 5.9.142.237
1 Invalid user mcserver from 106.243.125.195
1 Invalid user oracle from 47.89.30.90
1 Invalid user pappas from 221.194.57.246
1 Invalid user paraskev from 221.194.57.246
1 Invalid user parkins from 221.194.57.246
1 Invalid user parviz from 221.194.57.246
1 Invalid user pat from 221.194.57.246
1 Invalid user patel from 221.194.57.246
1 Invalid user patrice from 221.194.57.246
1 Invalid user patricia from 221.194.57.246
1 Invalid user patrick from 221.194.57.246
1 Invalid user patsy from 221.194.57.246
1 Invalid user patti from 221.194.57.246
1 Invalid user patty from 221.194.57.246
1 Invalid user paul from 221.194.57.246
1 Invalid user paula from 221.194.57.246
1 Invalid user pauline from 221.194.57.246
1 Invalid user pawan from 221.194.57.246
1 Invalid user payman from 221.194.57.246
1 Invalid user pedro from 221.194.57.246
1 Invalid user peebles from 221.194.57.246
1 Invalid user peggy from 221.194.57.246
1 Invalid user peh from 221.194.57.246
1 Invalid user penny from 221.194.57.246
1 Invalid user pentti from 221.194.57.246
1 Invalid user peraka from 221.194.57.246
1 Invalid user perry from 221.194.57.246
1 Invalid user pete from 221.194.57.246
1 Invalid user peter from 221.194.57.246
1 Invalid user pham from 221.194.57.246
1 Invalid user phil from 221.194.57.246
1 Invalid user philip from 221.194.57.246
1 Invalid user philippe from 221.194.57.246
1 Invalid user pi from 125.212.232.7
1 Invalid user pi from 185.110.132.54
1 Invalid user postgres from 168.61.151.213
1 Invalid user postgres from 40.115.42.208
1 Invalid user postgres from 40.76.197.199
1 Invalid user r00t from 213.85.31.170
1 Invalid user sfkfds from 128.199.50.75
1 Invalid user steam from 106.243.125.195
1 Invalid user test from 120.63.160.51
1 Invalid user test from 83.169.18.20
1 Invalid user ubnt from 185.130.5.200
1 Invalid user ubnt from 208.69.31.98
1 Invalid user ubnt from 45.32.58.26
1 Invalid user user from 208.69.31.98
1 Invalid user vagrant from 168.61.151.213
1 Invalid user vagrant from 23.105.14.236
1 Invalid user vagrant from 40.115.42.208
1 Invalid user vagrant from 40.76.197.199
1 Invalid user voldo from 5.9.142.237
1 Invalid user vyatta from 62.48.231.174
1 Invalid user vyos from 62.48.231.174
1 user from 81.200.59.163
1 user 357273277admin from 52.193.8.78
1 user a from 180.97.81.197
1 user a from 212.52.147.114
1 user aaron from 14.63.173.204
1 user aaron from 190.90.225.18
1 user aaron from 207.194.15.162
1 user ab from 190.90.225.18
1 user ab from 207.194.15.162
1 user admin from 184.75.214.42
1 user admin from 187.63.162.193
1 user admin from 195.154.46.203
1 user admin from 45.32.76.153
1 user admin from 46.148.18.162
1 user admin from 5.9.158.113
1 user admin from 52.193.8.78
1 user admin from 74.208.166.108
1 user admin from 91.183.49.65
1 user ajay from 58.242.3.210
1 user amelie from 85.69.155.61
1 user amy from 85.69.155.61
1 user ana from 85.69.155.61
1 user anais from 85.69.155.61
1 user andre from 85.69.155.61
1 user andrea from 85.69.155.61
1 user andreas from 85.69.155.61
1 user andy from 85.69.155.61
1 user ange from 85.69.155.61
1 user angele from 85.69.155.61
1 user anita from 85.69.155.61
1 user anja from 85.69.155.61
1 user anna from 85.69.155.61
1 user annchen from 85.69.155.61
1 user anne from 85.69.155.61
1 user annika from 85.69.155.61
1 user anton from 85.69.155.61
1 user antonia from 85.69.155.61
1 user anup from 85.69.155.61
1 user aram from 85.69.155.61
1 user arsene from 85.69.155.61
1 user arthur from 85.69.155.61
1 user arya from 85.69.155.61
1 user ashtyn from 85.69.155.61
1 user asma from 85.69.155.61
1 user asta from 85.69.155.61
1 user audrey from 85.69.155.61
1 user aureliia from 85.69.155.61
1 user avi from 85.69.155.61
1 user aydin from 85.69.155.61
1 user bastien from 85.69.155.61
1 user be from 223.4.200.247
1 user beatrice from 85.69.155.61
1 user becky from 85.69.155.61
1 user bedja from 85.69.155.61
1 user bot from 14.63.173.204
1 user git from 217.24.56.111
1 user guest from 188.214.58.162
1 user jenkins from 217.24.56.111
1 user jgarza from 54.147.178.184
1 user lenovo from 14.204.75.148
1 user lenovo from 180.128.252.1
1 user nicole from 221.194.57.246
1 user niel from 221.194.57.246
1 user nigel from 221.194.57.246
1 user nightwal from 221.194.57.246
1 user nikhil from 221.194.57.246
1 user nikki from 221.194.57.246
1 user nikolaos from 221.194.57.246
1 user nilson from 221.194.57.246
1 user nina from 221.194.57.246
1 user nino from 221.194.57.246
1 user noam from 221.194.57.246
1 user nobuhiko from 221.194.57.246
1 user nobuko from 221.194.57.246
1 user nolan from 221.194.57.246
1 user nondet from 221.194.57.246
1 user nora from 221.194.57.246
1 user noreen from 221.194.57.246
1 user norene from 221.194.57.246
1 user norma from 221.194.57.246
1 user norman from 221.194.57.246
1 user noshir from 221.194.57.246
1 user numerge from 78.31.65.228
1 user octavia from 221.194.57.246
1 user oivind from 221.194.57.246
1 user ojrind from 221.194.57.246
1 user olin from 221.194.57.246
1 user oliver from 221.194.57.246
1 user olivia from 221.194.57.246
1 user olivier from 221.194.57.246
1 user ollie from 221.194.57.246
1 user omead from 221.194.57.246
1 user onstad from 221.194.57.246
1 user oracle from 104.233.120.229
1 user oracle from 212.52.147.114
1 user orville from 221.194.57.246
1 user osulliva from 221.194.57.246
1 user oswald from 221.194.57.246
1 user othar from 221.194.57.246
1 user oussama from 221.194.57.246
1 user owen from 221.194.57.246
1 user paddy from 221.194.57.246
1 user padma from 221.194.57.246
1 user paige from 221.194.57.246
1 user pallab from 221.194.57.246
1 user palmer from 221.194.57.246
1 user pam from 221.194.57.246
1 user pamela from 221.194.57.246
1 user pandora from 221.194.57.246
1 user pi from 46.148.18.162
1 user sfkfds from 217.24.56.111
1 user shit from 104.239.249.95
1 user support from 158.69.124.31
1 user support from 62.210.88.211
1 user support from 78.8.174.70
1 user test from 168.61.210.46
1 user ubnt from 14.175.208.152
1 user ubnt from 158.69.124.31
1 user ubnt from 212.129.28.58
1 user ubnt from 212.129.55.113
1 user user from 104.239.232.87
1 user vagrant from 78.31.65.228
2 Invalid user cmsftp from 58.214.233.179
2 Invalid user nsrecover from 58.214.233.179
2 Invalid user t1na from 218.28.238.170
2 user admin from 208.67.1.130
2 user admin from 40.76.19.122
2 user admin from 93.174.89.87
2 user developer from 195.225.105.18
2 user developer from 198.11.247.46
2 user developer from 217.76.197.46
2 user postgres from 221.179.89.90
3 user developer from 5.39.5.48
3 user minecraft from 87.234.16.114