Citrix ADC

gRPC health check monitor

The gRPC health monitor probes the gRPC servers for its health status. The gRPC health monitor checks the overall health of the gRPC service or the health of a particular service. Currently, the Citrix ADC appliance support only the check method.

In the Citrix ADC appliance, The health check monitor is configured by setting the gRPC parameters such as gRPCHealthCheck gRPCStatusCode, gRPCServiceName, and httprequest in the HTTP2 monitor configuration. A client implementing the protocol queries the server for its status (healthy, not healthy, unknown, or service not implemented) and expects the status response from the service.

The following table gives details about the new gRPC parameters and its description:

gRPC parameters Value Description
gRPCHealthCheck Yes/No Enable or disable gRPC health check probe.
gRPCStatusCode Unsigned int (0-65535), Default: 12 Configure up to 16 gRPC status code. The appliance looks for the status code 0 in the status response. If it fails to receive 0, the service can set to up if any of the 16 code matches with the service status.
gRPCServiceName Service name within double quotes, Default = “” (empty string) Check the health of the particular service.

Configure the gRPC health monitor in HTTP/2 by using the command interface

To perform a gRPC health check probe, you must enable the health check service, configure the gRPC status code, and provide the gRPC service name for which the gRPC health check must be performed. At the command prompt, type:

add lb monitor <monitor_name> HTTP2 -httpRequest <string> -grpcHealthCheck ( YES | NO ) - grpcStatusCode <positive_integer> - grpcServiceName string>]


add lb monitor http2 HTTP2 -httprequest “POST /” – gRPCHealthCheck Yes -gRPCStatusCode 0 -grpcServiceName "ECHO"

Configure the gRPC health monitor in HTTP/2 by using the GUI

  1. Navigate to Traffic Management > Load Balancing > Monitors.
  2. Click Add.
  3. In the Create Monitor page, set the following parameters:

    1. Name. Name of the gRPC health monitor.
    2. Type. Select service type as HTTP/2.
    3. gRPC HealthCheck. Enable gRPC health check probe.
    4. gRPC StatusCode. The gRPC service status is “UP” only if the gRPC status code is zero or the configured value. The status goes “down” if the status code is a value other than zero or the configured value.
    5. gRPC Service name. Service for which the health check is performed.
  4. Create Create.

gRPC health check monitor configuration

gRPC health check monitor