Munin contributed plugins

=head1 APPLICABLE SYSTEMS

Virtualization server with VMs based on KVM may be able to track the network

traffic of their VMs, if the KVM processes are started in a specific way.

Probably proxmox-based virtualization hosts fit into this category.

You can easily check if your KVM processes are started in the expected way, by

running the following command:

  ps -ef | grep "netdev.*ifname="

The plugin can be used, if the above command outputs one line for every

currently running VM.

In all other cases you need to use other munin plugins instead, e.g. "libvirt".

KVM_INTERFACE_NAME_REGEX = re.compile("(?:^|,)ifname=([^,]+)(?:,|$)")

    for pid, vm_data in vms.items():

        vm_interface_names = get_vm_network_interface_names(pid)

        sum_incoming = 0

        sum_outgoing = 0

        interface_found = False

        with open("/proc/net/dev", "r") as net_file:

            for line in net_file.readlines():

                tokens = line.split()

                current_interface_name = tokens[0].rstrip(":").strip()

                if current_interface_name in vm_interface_names:

                    sum_incoming += int(tokens[1])

                    sum_outgoing += int(tokens[9])

                    interface_found = True

            if not interface_found:

                # we want to distinguish "no traffic" from "not found"

                sum_incoming = "U"

                sum_outgoing = "U"

            print("%s_in.value %s" % (vm_data, sum_incoming))

            print("%s_out.value %s" % (vm_data, sum_outgoing))

def get_vm_network_interface_names(pid):

    """ return the MAC addresses configured for network interfacs of a PID """

    result = set()

    for netdev_description in _get_kvm_process_arguments(pid, "netdev"):

        match = KVM_INTERFACE_NAME_REGEX.search(netdev_description)

        if match:

            result.add(match.groups()[0])

    return result