Product Documentation

Load Balancing

Feb 26, 2014
What are the various load balancing policies I can create on the NetScaler appliance?
You can create the following types of load balancing policies on the NetScaler appliance:
  • Least Connections
  • Round Robin
  • Least response time
  • Least bandwidth
  • Least packets
  • URL hashing
  • Domain name hashing
  • Source IP address hashing
  • Destination IP address hashing
  • Source IP - Destination IP hashing
  • Token
  • LRTM
Can I achieve the Web farm security by implementing load balancing using the NetScaler appliance?
Yes. You can achieve Web farm security by implementing load balancing using the NetScaler appliance. NetScaler appliance enables you to implement the following options of the load balancing feature:
  • IP Address hiding: Enables you to install the actual servers to be on private IP address space for security reasons and for IP address conservation. This process is transparent to the end-user because the NetScaler appliance accepts requests on behalf of the server. While in the address hiding mode, the appliance completely isolates the two networks. Therefore, a client can access a service running on the private subnet, such as FTP or a Telnet server, through a different VIP on the appliance for that service.
  • Port Mapping: Enables the actual TCP services to be hosted on non-standard ports for security reasons. This process is transparent to the end-user as the NetScaler appliance accepts requests on behalf of the server on the standard advertised IP address and port number.
What are various devices that I can use to load balance with a NetScaler appliance?
You can load balance following devices with a NetScaler appliance:
  • Server farms
  • Caches or Reverse Proxies
  • Firewall devices
  • Intrusion detection systems
  • SSL offload devices
  • Compression devices
  • Content Inspection servers
Why should I implement the load balancing feature for the website?
You can implement the Load balancing feature for the website to take the following advantages:
  • Reduce the response time: When you implement the load balancing feature for the website, one of the major benefits is the boost you can look forward to in load time. With two or more servers sharing the load of the web traffic, each of the servers runs less traffic load than a single server alone. This means there are more resources available to fulfill the client requests. This results in a faster website.
  • Redundancy: Implementing the load balancing feature introduces a bit of redundancy. For example, if the website is balanced across three servers and one of them does not respond at all, the other two can keep running and the website visitors do not even notice any downtime. Any load balancing solution immediately stops sending traffic to the backend server that is not available.
Why do I need to disable the Mac Based Forwarding (MBF) option for Link Load Balancing (LLB)?
  • If you enable the MBF option, the NetScaler appliance considers that the incoming traffic from the client and the outgoing traffic to the same client flow through the same upstream router. However, the LLB feature requires that the best path be chosen for the return traffic.
  • Enabling the MBF option breaks this topology design by sending the outgoing traffic through the router that forwarded the incoming client traffic.