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Diffstat (limited to 'resources/tools/topology/update_topology.py')
| -rwxr-xr-x | resources/tools/topology/update_topology.py | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/resources/tools/topology/update_topology.py b/resources/tools/topology/update_topology.py new file mode 100755 index 0000000000..d7a3929643 --- /dev/null +++ b/resources/tools/topology/update_topology.py @@ -0,0 +1,176 @@ +#!/usr/bin/env python2.7 +# Copyright (c) 2016 Cisco and/or its affiliates. +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at: +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +"""This executable python module gathers MAC address data from topology nodes. +It requires that all interfaces/port elements in topology have driver field. +This script binds the port in given node to set linux kernel driver and +extracts MAC address from it.""" + +import sys +import os +import re +from argparse import ArgumentParser + +import yaml + +from resources.libraries.python.ssh import SSH + +def load_topology(args): + """Load topology file referenced to by parameter passed to this script. + + :param args: arguments parsed from commandline + :type args: ArgumentParser().parse_args() + :return: Python representation of topology yaml + :rtype: dict + """ + data = None + with open(args.topology, 'r') as stream: + try: + data = yaml.load(stream) + except yaml.YAMLError as exc: + print 'Failed to load topology file: {0}'.format(args.topology) + print exc + raise + + return data + +def ssh_no_error(ssh, cmd): + """Execute a command over ssh channel, and log and exit if the command + fials. + + :param ssh: SSH() object connected to a node + :param cmd: Command line to execute on remote node + :type ssh: SSH() object + :type cmd: str + :return: stdout from the SSH command + :rtype: str + """ + ret, stdo, stde = ssh.exec_command(cmd) + if 0 != ret: + print 'Command execution failed: "{}"'.format(cmd) + print 'stdout: {0}'.format(stdo) + print 'stderr: {0}'.format(stde) + raise RuntimeError('Unexpected ssh command failure') + + return stdo + +def update_mac_addresses_for_node(node): + """For given node loop over all ports with PCI address and look for its MAC + address. + + This function firstly unbinds the PCI device from its current driver + and binds it to linux kernel driver. After the device is bound to specific + linux kernel driver the MAC address is extracted from /sys/bus/pci location + and stored within the node dictionary that was passed to this function. + :param node: Node from topology + :type node: dict + :return: None + """ + for port_name, port in node['interfaces'].items(): + if not port.has_key('driver'): + err_msg = '{0} port {1} has no driver element, exiting'.format( + node['host'], port_name) + raise RuntimeError(err_msg) + + ssh = SSH() + ssh.connect(node) + + # TODO: make following SSH commands into one-liner to save on SSH opers + + # First unbind from current driver + drvr_dir_path = '/sys/bus/pci/devices/{0}/driver'.format( + port['pci_address']) + cmd = '''\ + if [ -d {0} ]; then + echo {1} | sudo tee {0}/unbind ; + else + true Do not have to do anything, port already unbound ; + fi'''.format(drvr_dir_path, port['pci_address']) + ssh_no_error(ssh, cmd) + + # Then bind to the 'driver' from topology for given port + cmd = 'echo {0} | sudo tee /sys/bus/pci/drivers/{1}/bind'.\ + format(port['pci_address'], port['driver']) + ssh_no_error(ssh, cmd) + + # Then extract the mac address and store it in the topology + cmd = 'cat /sys/bus/pci/devices/{0}/net/*/address'.format( + port['pci_address']) + mac = ssh_no_error(ssh, cmd).strip() + pattern = re.compile("^([0-9A-Fa-f]{2}:){5}[0-9A-Fa-f]{2}$") + if not pattern.match(mac): + raise RuntimeError('MAC address read from host {0} {1} is in ' + 'bad format "{2}"'.format(node['host'], + port['pci_address'], mac)) + print '{0}: Found MAC address of PCI device {1}: {2}'.format( + node['host'], port['pci_address'], mac) + port['mac_address'] = mac + +def update_nodes_mac_addresses(topology): + """Loop over nodes in topology and get mac addresses for all listed ports + based on PCI addresses. + + :param topology: Topology information with nodes + :type topology: dict + :return: None + """ + + for node in topology['nodes'].values(): + update_mac_addresses_for_node(node) + +def dump_updated_topology(topology, args): + """Writes or prints out updated topology file. + + :param topology: Topology information with nodes + :param args: arguments parsed from command line + :type topology: dict + :type args: ArgumentParser().parse_args() + :return: 1 if error occured, 0 if successful + :rtype: int + """ + + if args.output_file: + if not args.force: + if os.path.isfile(args.output_file): + print ('File {0} already exists. If you want to overwrite this ' + 'file, add -f as a parameter to this script'.format( + args.output_file)) + return 1 + with open(args.output_file, 'w') as stream: + yaml.dump(topology, stream, default_flow_style=False) + else: + print yaml.dump(topology, default_flow_style=False) + return 0 + +def main(): + """Main function""" + parser = ArgumentParser() + parser.add_argument('topology', help="Topology yaml file to read") + parser.add_argument('--output-file', '-o', help='Output file') + parser.add_argument('-f', '--force', help='Overwrite existing file', + action='store_const', const=True) + parser.add_argument('--verbose', '-v', action='store_true') + args = parser.parse_args() + + topology = load_topology(args) + update_nodes_mac_addresses(topology) + ret = dump_updated_topology(topology, args) + + return ret + + +if __name__ == "__main__": + sys.exit(main()) + + |