OUROBOROS-TUTORIAL(7)

NAME
ouroboros-tutorial - A tutorial introduction to managing Ouroboros

SYNOPSIS
irm *

DESCRIPTION
This tutorial explains how to start and configure the Ouroboros Inter-Process Communication subsystem.

STARTING AND STOPPING THE IPC RESOURCE MANAGER DAEMON
For the tutorials, it is recommended to start the IRMd (you will need root privileges) as a user process, writing output to stdout (If your system has an IRMd running as a systemd service, you will need to stop it).
    $ irmd --stdout
Terminating the irmd can be done by pressing Ctrl+C if it is running in the foreground or by sending it a kill command for its process ID:
    $ kill 25959
The output should be
    ==25959== irmd(II): Ouroboros IPC Resource Manager daemon started...
    ==25959== irmd(II): IRMd shutting down...
    ==25959== irmd(II): Bye.

PINGING A SERVER APPLICATION OVER THE LOOPBACK ADAPTER
With a running irmd, let's create an IPC process. For this tutorial, we will create and bootstrap an eth-llc IPCP over the loopback interface. To observe what's going on, open another terminal window. Note that "ipcp bootstrap" will create an IPCP if an IPCP by that name does not yet exist (See ouroboros(8)).
    $ irm ipcp bootstrap type eth-llc name llc layer llc if lo
    ==23918== irmd(II): Created IPCP 23932.
    ==23932== ipcpd/eth-llc(II): Using raw socket device.
    ==23918== irmd(II): Bootstrapped IPCP 23932 in layer llc.
Now that we have the IPCP bootstrapped, it can act as a local network layer that can provide full connectivity between all processes in the system. Let's test it using the oping application. First, let's choose a name for the server ("my.oping.server") and register in the llc layer.
    $ irm reg name my.oping.server layer llc
The IRMd should respond with
    ==23918== irmd(II): Registered my.oping.server in llc as 716016b1.
Now start a server of oping in the background (or in a different terminal) and bind the process to the name "my.oping.server" (replace the correct process id for your system).
    $ oping -l &
    [1] 24063
    $ irm bind process 24063 name my.oping.server
With the server up and running, let's connect a client and send 3 pings:
    $ oping -n my.oping.server -c 3
    Pinging my.oping.server with 64 bytes of data: 64 bytes from my.oping.server: seq=0 time=0.475 ms
    64 bytes from my.oping.server: seq=1 time=0.304 ms
    64 bytes from my.oping.server: seq=2 time=0.398 ms --- my.oping.server ping statistics ---
    3 SDUs transmitted, 3 received, 0% packet loss, time: 3001.011 ms
    rtt min/avg/max/mdev = 0.304/0.392/0.475/0.086 ms
That's all there is to it! The IRMd should log the flow allocation. There are two endpoints of the flow (port_id's 0 and 1), one for the server (1) and one for the client (0). After the flow request, a new port_id is created at the server side (port_id 1) and then a previously pending flow (on port_id 0) is allocated following the response from the server. When the communication is done, the flow is deallocated and the resources (port_id's 0 and 1) are released.
    ==23918== irmd(II): Flow request arrived for my.oping.server.
    ==23918== irmd(II): Flow on port_id 1 allocated.
    ==23918== irmd(II): Flow on port_id 0 allocated.
    ==23918== irmd(II): Completed deallocation of port_id 0 by process 23932.
    ==23918== irmd(II): Completed deallocation of port_id 1 by process 23932.

TERMINOLOGY
Please see ouroboros-glossary(7).

SEE ALSO
ouroboros(8)

COLOPHON
This page is part of the Ouroboros project, found at http://ouroboros.ilabt.imec.be These man pages are licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/