Cisco Systems OL-7029-01 manual Probe

Chapter 2 Content Switching Module with SSL Commands

probe

probe

To configure a probe and probe type for health monitoring, and then enter the probe configuration submode, use the probe command. To remove a probe from the configuration, use the no form of this command.

probe probe-name{http icmp telnet tcp ftp smtp dns udp script}

	no probe probe-name
Syntax Description	probe-name	Name of the probe; the character string is limited to 15 characters.
	http	Creates an HTTP probe with a default configuration.
	icmp	Creates an ICMP probe with a default configuration.
	telnet	Creates a Telnet probe with a default configuration.
	tcp	Creates a TCP probe with a default configuration.
	ftp	Creates an FTP probe with a default configuration.
	smtp	Creates an SMTP probe with a default configuration.
	dns	Creates a DNS probe with a default configuration.
	udp	Creates a UPD probe with a default configuration.
	script	Creates a script probe with a default configuration.
Defaults	This command has no default settings.
Command Modes	Module CSM configuration submode
Command History	Release	Modification
	CSM release 1.1(1)	This command was introduced.
	CSM-S release 1.1(1)	This command was introduced.
Usage Guidelines	A probe can be assigned to a server farm in serverfarm submode. The UDP probe requires ICMP because
	otherwise the UDP probe will be unable to detect when a server has gone down or has been disconnected.
	You must associate UDP to the supervisor engine and then configure ICMP.

Because the UDP probe is a raw UDP probe, the CSM uses a single byte in the payload for probe responses. The CSM does not expect any meaningful response from the UDP application. The CSM uses the ICMP unreachable message to determine if the UDP application is not reachable. If there is no ICMP unreachable message in the receive timeout, then the CSM assumes that the probe is operating correctly.

If the IP interface of the real server is down or disconnected, the UDP probe does not know that the UDP application is unreachable. You must configure the ICMP probe in addition to the UDP probe for any server.

The CSM uses the DNS probe as the high-level UDP application. You also can use a TCL script to configure this probe.

Catalyst 6500 Series Switch Content Switching Module with SSL Command Reference

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