HowTo: Restart SSH on Oracle Linux Server 6

 Send a HUP signal to the sshd process.

# cat /etc/oracle-release
Oracle Linux Server release 6.4

# ps -eaf | grep sshd
root     20483     1  0 09:29 ?        00:00:00 /usr/sbin/sshd
root     20636 20147  0 09:34 pts/0    00:00:00 grep sshd

# cat /var/run/sshd.pid
20483

# kill -HUP 20483

or

# kill -HUP `cat /var/run/sshd.pid`