If you are planning or implementing CAS Array and wondering what are the options for load balance your CAS servers here is quick reference to remember.
- HLB ( hardware load balance ) solution, This is what is being recommended.
- SLB ( Software load balance) solution, This is also recommended.
- Windows NLB ( network load balancing) This is no longer recommended
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The main reason why HLB & SLB are recommended , these solutions provides “ Application awareness” and also managing CAS servers behind these type of deployment is very easy and efficient.
MAPI Request comes to HLB , HLB has CAS servers published within , Administrator easily can stop MAPI request going specific CAS server etc. These deployments are also far more stable and easy to configure IMO. I think we will see more official statement soon and expecting to see ending support recommendations to HLB with CAS in the near future.