1. It is possible that the IP conflicts with others, just change the IP
2. There may also be file permissions. Change it:
cd /etc/ssh/ chmod 600 ssh_host_* chmod 644 *.pub
3. It may also be a firewall problem
/etc/init.d/iptables status // Look at the firewall status first chkconfig iptables off // Command to close
or:
#Stop firewall systemctl stop firewalld.service #Prohibit firewall startup systemctl disable firewalld.service