Network Router User Manual

Chapter 17: Web Hosting Configuration Guide
236 SmartSwitch Router User Reference Manual
Verifying Servers and Applications
The SSR automatically performs the following types of verification for the attached load
balancing servers/applications:
• Verifies the state of the server by sending a ping to the server at 5-second intervals. If
the SSR does not receive a reply from a server after four ping requests, the server is
considered to be “down.”
• Checks that an application session on the server can be established by doing a simple
TCP handshake with the application on the configured physical port of the server at
15-second intervals. If the SSR does not receive a reply from the application after four
tries, the application is considered to be “down.”
You can change the intervals at which pings or handshakes are attempted and the number
of times that the SSR retries the ping or handshake before considering the server or
application to be “down.” You can change these parameters for all servers in a load
balancing group or for specific servers.
You can change the ping intervals and the number of retries by entering the following
Configure mode commands:.
You can change the handshake intervals and the number of retries by entering the
following Configure mode commands:
Set ping interval for all servers in
specified group.
load-balance set group-options <group
name>
ping-int <seconds>
Set ping interval for specific
server.
load-balance set server-options <ipaddr>
ping-int
<seconds> port <port number>
Set number of ping retries for all
servers in specified group.
load-balance set group-options <group
name>
ping-tries <number>
Set number of ping retries for
specific server.
load-balance set server-options <ipaddr>
ping-tries <number> port <port number>
Set handshake interval for all
servers in specified group.
load-balance set group-options <group
name>
app-int <seconds>
Set handshake interval for
specified server.
load-balance set server-options <group
name>
app-int <seconds> port <port
number>
Set number of handshake retries
for all servers in specified group.
load-balance set group-options <group
name>
app-tries <number>
Set number of verification retries
for specified server.
load-balance set server-options <group
name>
app-tries <number> port <port
number>