Title: vrrp notes
Subject: Virtual Router Redundancy Protocol - a form of HA on linux
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Linux Director:
 	One active at a time.
	Active - Accepts traffic for the floating IP address using LVS.
		 Acts as the gateway router for internal network.
	Both Directors monitor each other using Heartbeat.

  When active diretor fails, secondary will take over floating ip.

  Floading ip advertised via dns.

  When director decides which real server to route a TCP/IP connection, routing
  stay's constant for the life of the TCP/IP connetion.

  Ldirectord periodically requesting a known page from a real server.  
  If a real server fails, the server is taken out of the pool 
  The real servers and will be reinserted once it comes back on line. 
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Linux Virtual Server-
	Direct Routing- 
	  Configured to accept traffic for the virtual 
	  server's IP address, by using a dummy interface.
	  The IP packet is not modified
	IP-IP Encapsulation-
	  Forwarded packets are encapsulated in an IP packet.
	  The main advantage is that real servers can be on different networks
	Network Address Translation-
Virtual Service
	IP Address, Port and Protocol-
	Firewall-Mark-