Specifications

Chapter 6: Administering Virtual Clusters
68 Equalizer Installation and Administration Guide
• HTTP, Equalizer passes web server requests and route requests to particular servers
based on the content of the request and various load-balancing criteria. (This protocol
supports Layer 7 load balancing.)
• HTTPS, Equalizer passes secure web server requests and route requests to particular
servers based on the content of the request and various load-balancing criteria. (This
protocol supports Layer 7 load balancing.)
• L4 TCP, Equalizer passes TCP-based requests and route requests based on configured
load balancing criteria, the IP address, and TCP port number. Load balancing based on
generic connection protocols can be quite efficient; however, routing decisions cannot
take into account the content of the request. (This protocol supports Layer 4 load
balancing.)
• L4 UDP, Equalizer passes TCP-based requests and route requests based on configured
load balancing criteria, the IP address, and UDP port number. Load balancing based on
the generic connection protocols can be quite efficient, but routing decisions cannot take
into account the content of the request. (This protocol supports Layer 4 load balancing.)
When you first open the add cluster screen, it displays the fields for the HTTP protocol, as
shown in Figure 38 on page 67. When you change the protocol in the drop down box, the
available fields on the form change to include the fields appropriate for the chosen protocol.
5. Enter the ip address, which is the dotted decimal IP address of the cluster. The IP address of the
cluster is the external address (for example,
199.146.85.0) with which clients connect to the
cluster.
6. For HTTP and HTTPS protocol clusters, enter the port: the numeric port number on the
Equalizer to be used for traffic between the clients and the cluster. For HTTP clusters, the port
defaults to 80. For HTTPS clusters, the port defaults to 443. This port also becomes the default
port for servers added to the cluster (though servers can use a different port number than the
one used by the cluster).
For L4 UDP and L4 TCP protocol clusters, a port range can be defined using the start_port
and end_port fields. These are the ports on the Equalizer to be used to send traffic to the
servers in the cluster. Port ranges allow Equalizer users to create a single cluster to control the
traffic for multiple, contiguous ports. There are two typical uses for port ranges:
• Specific applications that require a range of ports.
• The need to open up access to servers behind the Equalizer for all ports.
Enter the first port number in the start_port field (which is required). Enter the end port
number in the end_port field. (If end_port is not visible, check the advanced flag.)
When the end_port field is left with a value of zero (the default), Equalizer disables the port
range feature and uses the start_port as the server port. The start_port cannot be higher than
end_port when end_port is nonzero.
Note – On the Equalizer E250si, Layer 7 content-based load balancing is not supported;
HTTP and HTTPS are not available choices for protocol. Load balancing of HTTP and
HTTPS packets on the E250si is accomplished through Layer 4 TCP load balancing.