Hamachi on centos

create a adhoc mesh network on through hamachi web interface

yum install redhat-lsb

download the hamachi binary from - https://secure.logmein.com/labs/

rpm -ivh

sudo vi /var/lib/logmein-hamachi/h2-engine-override.cfg

Ipc.User <>
sudo /etc/init.d/logmein-hamachi start

sudo hamachi do-join
sudo hamachi go-online  

ifconfig

should give comething like 

ham0      Link encap:Ethernet  HWaddr ##.##.##.##
          inet addr:##.##.##.##  Bcast:25.255.255.255  Mask:255.0.0.0
          UP BROADCAST RUNNING MULTICAST  MTU:1404  Metric:1
          RX packets:26 errors:0 dropped:0 overruns:0 frame:0
          TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:500
          RX bytes:2264 (2.2 KiB)  TX bytes:672 (672.0 b) 
That whould imply that the hamachi client is up and working. Now open all the communcaiton for hamachi through the firewall

iptables -A INPUT -i ham0 -p all -j ACCEPT

That it..now ping form the remote machine ..your machine should be reachable via the hamachi vpn..