By configuring MIM server deployments you can provide high network availability and load balanced configurations. This document will detail how to provide high network availability by combining multiple physical machines into a single logical server instance on the network.
In a typically failure scenario with independent servers, clients are forced to reconnect on a different host name and possibly server port. In a high network availability scenario, clients reconnect to the original host and port configurations and are routed to an available server. Specifically, when using the MIMIC or Excel applications, the user will have to resubmit the failed request, but not change configurations or take other actions. The failure will appear the same as network congestion or a cable failure.
Both proper configuration of the servers and network is necessary to reach high availability.
How it works:
Clients access a master server via a known name or IP address.
This IP address can be distributed to many real IP addresses of master servers.
When the client requests a slave from the master, the IP of the real slave hosting machine is returned.
The client processes requests with this slave.
The next request begins this process from the start possibly routed to a different master and slave pair.
The MIM servers in the high availability group should be configured identically. This way, the clients will see the same schema. The server group should run the same updates. The updates are not synchronized, but similar hardware setups will run the updates in nearly identical time-frames.
The network provides the means of using a single IP address or machine name to reach multiple machines. Since all of the machines are on the same port, any machine can receive the client’s request.
There are several ways to achieve this.
Use a loading balancing product like F5’s Application Switch
Use a software load balancing product like Zeus Load Balancer
Use round robin IP forwarding in a CISCO router.
Use round robin DNS
Use Linux LVS
 | It is not possible for LIM to test all of these configurations. LIM has used the Zeus Load Balancer with good results. |