Infrap4d User Guide 

infrap4d is the P4 Control Plane server daemon. It consists of:

a P4Runtime server, which configures the P4 packet processing pipeline
a gNMI server, which performs port configuration
a Kernel Monitor, which listens for network events and updates tables in the P4 pipeline.

Syntax 

infrap4d \
    [--help | --helpshort | --helpon MODULE] \
    [--[no]detach] \
    [--disable-krnlmon] \
    [other options]

infrap4d is located in the sbin directory of the install tree.

Command-Line Flags 

Flag prefix 

A flag may be prefixed with either one or two hyphens. -help and --help are equivalent.

Underscores vs. hyphens 

Underscores and hyphens may be used interchangeably within the name of a flag. --disable_krnlmon and --disable-krnlmon are equivalent.

Boolean values 

A Boolean value of true may be expressed as true, yes, on, or 1, or by specifying the flag without a value. For example:

-detach
-detach=true
-detach yes

A Boolean value of false may be expressed as false, no, off, or 0, or by prefixing the flag name with no. For example:

-nodetach
-detach=no
-detach 0

Infrap4d uses the Google gflags library to process command-line flags. Technical documentation is available in How to Use Gflags. This document is intended for developers using the library, but it has some information on Special Flags as well.

Help Options 

infrap4d provides several ways to display lists of supported flags. The most useful of these are:

--helpshort

Displays just the flags that are specific to the main module (infrap4d_main).

--helpon MODULE

Displays just the flags that are defined by the named module.

MODULE is the name of the source file in which the flags are defined, without the .cc suffix; for example, logging or tdi_hal_flags.

--help

Displays the flags for all modules. The list is long.

The help flags are defined by the gflags_reporting module.

infrap4d --helpon gflags_reporting

Infrap4d Options 

These flags influence the way infrap4d starts up. They are defined by the infrap4d_main module.

--detach

Run infrap4d in detached mode. type: Boolean. default: true.

In detached mode, infrap4d runs as a separate process, as a daemon. In non-detached mode, it runs in the current process, as an application.

--disable-krnlmon

Do not start the Kernel Monitor. type: Boolean. default: false.

Other Options 

See the Infrap4d Flags Reference for a complete list of flags supported by infrap4d.

Verifying Settings 

gflags processes all the flags on the command line before it displays help output. The help output includes the current value of any flags that have been set, as the following example demonstrates.

$ ./install/sbin/infrap4d -disable-krnlmon -helpshort
infrap4d: P4Runtime server for P4 Control Plane.

Flags from /home/dfoster/work/latest/infrap4d/infrap4d_main.cc:
  -detach (Run infrap4d in detached mode) type: bool default: true
  -disable_krnlmon (Run infrap4d without krnlmon support) type: bool
   default: false currently: true

gflags doesn’t always do what you expect. This is a way to see the effect of the flags on the command line.