Configuring a Probe for TWCB (S-Series)

TWCB provides the ability to assign two probes to monitor a cache server. ICMP probe monitoring of a cache server occurs by default, using the predefined ICMP probe $twcb_default, assigned to probe one. See Preset Default ICMP Probes for preset default ICMP probe details.

Probes are assigned to a cache server configuration using the faildetect probe command in cache server configuration mode. When assigning a probe to a cache server, specify probe one or two, and the name of the probe. Any preexisting probe is overwritten when assigning a probe.

Default ICMP probes can not be assigned by specifying the name of the probe. When probe one has not been administratively configured, the default ICMP probe for that server context is auto-configured for probe one.

Layer 7 real server applications can be verified by configuring a TCP probe for application content verification.

This example shows how to:

  • Create a TCP probe named TCP-HTTP
  • Configure the ACV request and reply strings
  • Place the probe inservice
  • Display a detailed level of configuration information for the probe
  • Assign the probe to probe one of the 186.89.10.51 cache server on the TWCB server farm s1Server:
  • Assign port 8080 as the TCP port to be monitored.
  • Enable the real server configuration
    System(su)->configure
    System(su-config)->probe TCP-HTTP tcp
    System(su-config-probe)->inservice
    System(su-config-probe)->acv request “GET / HTTP/1.1\\r\\nHost: 2.0.0.5\\r\\n\\r\\n”
    System(su-config-probe)->acv reply “HTTP/1.1 200 OK\\r\\n”
    System(su-config-probe)->show probe TCP-HTTP detail
    Probe:                        TCP-HTTP  Type:                           tcp-acv
    Administrative state:        inservice  Session count:                        1
    Fail-detect count:                   3  Pass-detect count:                    3
    Fail-detect interval:                5  Pass-detect interval:                 5
    3-way TCP handshake wait time:       5  Server response wait time:           10
    Application Content Verification:
     Request-string: GET / HTTP/1.1\\r\\nHost: 2.0.0.5\\r\\n\\r\\n
     Reply-string:   HTTP/1.1 200 OK\\r\\n
     Close-string:
     Search-Depth:   255
    System(su-config-probe)->exit
    System(su-config)->ip twcb wcserverfarm s1Server
    System(config-twcb-wcsfarm)->cache 186.89.10.51
    System(config-twcb-cache)->faildetect probe one TCP-HTTP
    System(config-twcb-cache)->faildetect app-port 8080
    System(config-twcb-cache)->inservice
    System(config-twcb-cache)->