Specifications

Chapter 4: Configuring the High-Level Network
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value of *:*. Either or both wildcard symbols can be replaced by an explicit
dest value by creating a new monitor based on http. This is referred to as
node and port aliasing, described in the following section.
Using node and port aliasing
Usually the health of a node is checked by pinging that node. For this reason
the dest attribute in the monitor template is always set to "*" or "*:*". This
causes the monitor instance created for a node to take that node’s address or
address and port as its destination. An explicit dest value forces the instance
destination to a specific address and/or port which may not be that of the
node. This causes the monitor to ping that forced destination by an
unspecified path. Suppose, for example, that the association performed
using http instead used a monitor my_http with a dest value of *:443. The
node association command would be identical except that http is now
replaced with my_http:
b node 11.12.11.20:80 11.12.11.21:80 11.12.11.22:80 monitor use my_http
This creates three instances of the monitor with the following dest values as
shown in Figure 4.73.
This is referred to as port aliasing. The node itself can also be aliased, by
assigning an explicit address to dest. For example, dest could set to
11.11.11.1:80. This is called node aliasing and for the nodes
+- NODE 11.12.11.20:80 UP
| |
| +- my_http
| 11.12.11.20:443 up enabled
|
+- NODE 11.12.11.21:80 UP
| |
| +- my_http
| 11.12.11.21:443 up enabled
|
+- NODE 11.12.11.22:80 UP
|
+- my_http
11.12.11.22:443 up enabled
Figure 4.73 Node ports aliased