4.1.0 HP PolyServe Matrix Server administration guide (T5392-96073, October 2010)

15 Configure service monitors
Service monitors are typically used to monitor a network service such as HTTP or FTP.
If a service monitor indicates that a network service is not functioning properly on
the primary server, Matrix Server can transfer the network traffic to a backup server
that also provides that network service.
Overview
Before creating a service monitor for a particular service, you will need to configure
that service on your servers. For example, you could configure a Web server
application to provide HTTP service and then create a service monitor for HTTP. A
service can run regardless of Matrix Server monitoring.
Service monitors and virtual hosts
A service monitor is associated with a specific virtual host; the monitored service
must be configured on all servers supporting that virtual host. Using virtual hosts
enables Matrix Server to switch traffic quickly between servers. If the service being
monitored goes down on the primary server, Matrix Server moves the virtual host
traffic to a backup server, which then handles the traffic for the service.
If you add another server to the configuration for a virtual host, the service monitors
assigned to that virtual host are automatically added to the new server. Similarly, if
a server is removed from the configuration, the service monitors assigned to the virtual
host are automatically removed from that server. Service monitor parameters (such
as probe severity, Start scripts, and Stop scripts) are consistent across all servers
configured for a virtual host.
Service monitors and failover
If a monitored service fails, Matrix Server attempts to relocate any virtual hosts
associated with the service monitor to a network interface on a healthier server.
However, if there are multiple failures in the cluster or the virtual host does not have
a backup network interface on another server, Matrix Server may not be able to
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