The image maxav010.gif shows the redundant network components in the primary site of an MAA environment.
In the database server tier, "heartbeats" connect the two RAC instances and also the active and inactive switches. The instances have a network connection to both switches. The switches have a network connection to a router. An active firewall and an inactive firewall separate the database server tier from the application server tier. A heartbeat connects the two firewalls.
The application server tier contains application/web servers, IMAP servers, and LDAP servers. The servers alhave a network connection to both the active and inactive switches. The active switches connect to an active hardware-based load balancer. The inactive switches connect to a standby hardware-based load balancer. There is a heartbeat between the active and inactive switches. An active firewall and an inactive firewall separate the application server tier from the client tier. There is a heartbeat between the firewalls.
The client tier is partially shown. It contains two routers and a WAN traffic manager. The routers are connected to both firewalls and each other, as well as to the switches in the application server tier. They are also connected to the WAN traffic manager.
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