ADC

相依igure reverse monitoring for a service

A reverse monitor marks a service as DOWN if the probe criteria are satisfied and UP if they are not satisfied. For example, if you want a backup service to receive traffic only when the primary service is DOWN, you can bind a reverse monitor to the secondary service but configure it to probe the primary service.

The Citrix ADC appliance supports the following reverse monitors:

  • HTTP
  • ICMP
  • TCP (from release 11.1 build 49.x)

相依iguring HTTP Reverse Monitoring for a Service

The following table describes the conditions of HTTP direct and reverse monitoring for a service:

反对dition Direct Reverse
反对nection not established. Fail Fail
HTTP response code matches the probe’s specifications. Success Fail
HTTP response code does not match the probe’s specifications. Fail Success
Probe timed out. Fail Fail

To configure HTTP reverse monitoring for a service by using the CLI

At the command prompt, type:

add lb monitor  HTTP -respCode 200 -httpRequest "HEAD /" -destIP  -destPort 80 -reverse YES bind service  -monitorname  

相依iguring ICMP Reverse Monitoring for a Service

The following table describes the conditions of ICMP direct and reverse monitoring for a service:

反对dition Direct Reverse
ICMP echo reply is received. Success Fail
Probe timed out. Fail Success

To configure ICMP reverse monitoring for a service by using the CLI

At the command prompt, type:

add lb monitor  PING -destIP  -reverse YES bind service  -monitorname  

相依iguring TCP Reverse Monitoring for a Service

If a direct TCP monitor receives a RESET in response to a monitor probe, the service is marked DOWN. However, if a reverse TCP monitor receives a RESET response, the probe is considered successful, and the service is marked UP.

The following table describes the conditions of TCP reverse monitoring for a service:

反对dition Direct Reverse
TCP connection is established. Success Fail
Probe timed out. Fail Fail
Response to probe is RESET. Fail Success

To configure TCP reverse monitoring for a service by using the CLI

At the command prompt, type:

add lb monitor  TCP –destip  -destport  –reverse YES bind service  -monitorname  

To configure reverse monitoring by using the GUI

  1. Navigate toTraffic Management>Load Balancing>Monitors.
  2. Create an HTTP, ICMP, or TCP monitor and selectReverse.
相依igure reverse monitoring for a service