sshd attacks

I've been getting attacks against my sshd server:

Failed logins from these:
   admin/password from 12.47.62.139: 2 Time(s)
   admin/password from 134.21.2.227: 2 Time(s)
   guest/password from 12.47.62.139: 1 Time(s)
   guest/password from 134.21.2.227: 1 Time(s)
   guest/password from 210.1.9.227: 1 Time(s)
   guest/password from 61.193.179.162: 1 Time(s)
   root/password from 12.47.62.139: 3 Time(s)
   root/password from 134.21.2.227: 3 Time(s)
   test/password from 12.47.62.139: 2 Time(s)
   test/password from 134.21.2.227: 2 Time(s)
   test/password from 210.1.9.227: 1 Time(s)
   test/password from 61.193.179.162: 1 Time(s)
   user/password from 12.47.62.139: 1 Time(s)
   user/password from 134.21.2.227: 1 Time(s)

If you have one of these common accounts, shut off logins from them:

## lines added to /etc/ssh/sshd_config
PermitRootLogin no
DenyUsers admin guest test user
## EOF