unlock a deny host

1.
$ service denyhosts stop

2.
$ vim /etc/hosts.deny
delete the IP from the file

3.
$ cd /va/lib/denyhosts
$ grep -iRH IP ./*

[root@server denyhosts]# grep -iRH IP ./*

./hosts:IP:0:Sun Feb  9 11:27:57 2014

./hosts-restricted:IP:0:Sun Feb  9 11:27:57 2014

./hosts-root:IP:0:Sun Feb  9 11:27:57 2014

./hosts-valid:IP:11:Sun Feb  9 11:31:57 2014

./users-hosts:username - IP:11:Sun Feb  9 11:31:57 2014

delete the IPs from all of the files. 

4. 

$ service denyhosts start