NAME

ngctl — netgraph control utility

SYNOPSIS

DESCRIPTION

The ngctl utility creates a new netgraph node of type socket which can be used to issue netgraph commands. If no -f flag is given, no command is supplied on the command line, and standard input is a tty, ngctl will enter interactive mode. Otherwise ngctl will execute the supplied command(s) and exit immediately.

Nodes can be created, removed, joined together, etc. ASCII formatted control messages can be sent to any node if that node supports binary/ASCII control message conversion.

In interactive mode, ngctl will display any control messages and data packets received by the socket node. In the case of control messages, the message arguments are displayed in ASCII form if the originating node supports conversion.

The options are as follows:

-f filename

Read commands from the named file. A single dash represents the standard input. Blank lines and lines starting with a “#” are ignored. Note that when the -j jail option is specified, the file will be opened before attaching to the jail and then be processed inside the jail.

-j jail

Perform the actions inside the jail.

ngctl will first attach to the jail (by jail id or jail name) before performing the effects.

This allows netgraph nodes of jail to be created, modified, and destroyed even if the ngctl binary is not available in jail.

-n nodename

Assign nodename to the newly created netgraph node. The default name is ngctlXXX where XXX is the process ID number.

-d

Increase the debugging verbosity level.

COMMANDS

The currently supported commands in ngctl are:

config     get or set configuration of node at <path>
connect    Connects hook <peerhook> of the node at <relpath> to <hook>
debug      Get/set debugging verbosity level
dot        Produce a GraphViz (.dot) of the entire netgraph.
help       Show command summary or get more help on a specific command
list       Show information about all nodes
mkpeer     Create and connect a new node to the node at "path"
msg        Send a netgraph control message to the node at "path"
name       Assign name <name> to the node at <path>
read       Read and execute commands from a file
rmhook     Disconnect hook "hook" of the node at "path"
show       Show information about the node at <path>
shutdown   Shutdown the node at <path>
status     Get human readable status information from the node at <path>
types      Show information about all installed node types
write      Send a data packet down the hook named by "hook".
quit       Exit program

Some commands have aliases, e.g., “ls” is the same as “list”. The “help” command displays the available commands, their usage and aliases, and a brief description.

EXIT STATUS

The ngctl utility exits 0 on success, and >0 if an error occurs.

SEE ALSO

netgraph(3), netgraph(4), nghook(8)

HISTORY

The netgraph system was designed and first implemented at Whistle Communications, Inc. in a version of FreeBSD 2.2 customized for the Whistle InterJet.

AUTHORS

Archie Cobbs <archie@whistle.com>