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#!/usr/bin/env python3 |
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"""Healthchecker for exabgp. |
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This program is to be used as a process for exabgp. It will announce |
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some VIP depending on the state of a check whose a third-party program |
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wrapped by this program. |
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To use, declare this program as a process in your |
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:file:`/etc/exabgp/exabgp.conf`:: |
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neighbor 192.0.2.1 { |
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router-id 192.0.2.2; |
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local-as 64496; |
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peer-as 64497; |
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} |
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process watch-haproxy { |
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run python -m exabgp healthcheck --cmd "curl -sf http://127.0.0.1/healthcheck" --label haproxy; |
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} |
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process watch-mysql { |
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run python -m exabgp healthcheck --cmd "mysql -u check -e 'SELECT 1'" --label mysql; |
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} |
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Use :option:`--help` to get options accepted by this program. A |
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configuration file is also possible. Such a configuration file looks |
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like this:: |
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debug |
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name = haproxy |
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interval = 10 |
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fast-interval = 1 |
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command = curl -sf http://127.0.0.1/healthcheck |
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The left-part of each line is the corresponding long option. |
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When using label for loopback selection, the provided value should |
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match the beginning of the label without the interface prefix. In the |
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example above, this means that you should have addresses on lo |
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labelled ``lo:haproxy1``, ``lo:haproxy2``, etc. |
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""" |
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import sys |
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import os |
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import subprocess |
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import re |
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import logging |
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import logging.handlers |
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import argparse |
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import signal |
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import time |
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import collections |
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from ipaddress import ip_network |
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from ipaddress import ip_address |
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logger = logging.getLogger("healthcheck") |
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def enum(*sequential): |
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"""Create a simple enumeration.""" |
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return type(str("Enum"), (), dict(zip(sequential, sequential))) |
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def setargs(parser): |
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# fmt: off |
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g = parser.add_mutually_exclusive_group() |
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g.add_argument("--silent", "-s", action="store_true", default=False, help="don't log to console") |
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g.add_argument("--syslog-facility", "-sF", metavar="FACILITY", nargs='?', const="daemon", default="daemon", help="log to syslog using FACILITY, default FACILITY is daemon") |
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g.add_argument("--no-syslog", action="store_true", help="disable syslog logging") |
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parser.add_argument("--debug", "-d", action="store_true", default=False, help="enable debugging") |
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parser.add_argument("--no-ack", "-a", action="store_true", default=False, help="set for exabgp 3.4 or 4.x when exabgp.api.ack=false") |
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parser.add_argument("--sudo", action="store_true", default=False, help="use sudo to setup ip addresses") |
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parser.add_argument("--name", "-n", metavar="NAME", help="name for this healthchecker") |
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parser.add_argument("--config", "-F", metavar="FILE", type=open, help="read configuration from a file") |
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parser.add_argument("--pid", "-p", metavar="FILE", type=argparse.FileType('w'), help="write PID to the provided file") |
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parser.add_argument("--user", metavar="USER", help="set user after setting loopback addresses") |
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parser.add_argument("--group", metavar="GROUP", help="set group after setting loopback addresses") |
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g = parser.add_argument_group("checking healthiness") |
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g.add_argument("--interval", "-i", metavar='N', default=5, type=float, help="wait N seconds between each healthcheck (zero to exit after first announcement)") |
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g.add_argument("--fast-interval", "-f", metavar='N', default=1, type=float, dest="fast", help="when a state change is about to occur, wait N seconds between each healthcheck") |
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g.add_argument("--timeout", "-t", metavar='N', default=5, type=int, help="wait N seconds for the check command to execute") |
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g.add_argument("--rise", metavar='N', default=3, type=int, help="check N times before considering the service up") |
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g.add_argument("--fall", metavar='N', default=3, type=int, help="check N times before considering the service down") |
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g.add_argument("--disable", metavar='FILE', type=str, help="if FILE exists, the service is considered disabled") |
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g.add_argument("--command", "--cmd", "-c", metavar='CMD', type=str, help="command to use for healthcheck") |
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g = parser.add_argument_group("advertising options") |
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g.add_argument("--next-hop", "-N", metavar='IP', type=ip_address, help="self IP address to use as next hop") |
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g.add_argument("--ip", metavar='IP', type=ip_network, dest="ips", action="append", help="advertise this IP address or network (CIDR notation)") |
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g.add_argument("--local-preference", metavar='P', type=int, default=-1, help="advertise with local preference P") |
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g.add_argument("--deaggregate-networks", dest="deaggregate_networks", action="store_true", help="Deaggregate Networks specified in --ip") |
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g.add_argument("--no-ip-setup", action="store_false", dest="ip_setup", help="don't setup missing IP addresses") |
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g.add_argument("--dynamic-ip-setup", default=False, action="store_true", dest="ip_dynamic", help="delete existing loopback ips on state down and " "disabled, then restore loopback when up") |
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g.add_argument("--label", default=None, help="use the provided label to match loopback addresses") |
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g.add_argument("--start-ip", metavar='N', type=int, default=0, help="index of the first IP in the list of IP addresses") |
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g.add_argument("--up-metric", metavar='M', type=int, default=100, help="first IP get the metric M when the service is up") |
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g.add_argument("--down-metric", metavar='M', type=int, default=1000, help="first IP get the metric M when the service is down") |
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g.add_argument("--disabled-metric", metavar='M', type=int, default=500, help="first IP get the metric M when the service is disabled") |
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g.add_argument("--increase", metavar='M', type=int, default=1, help="for each additional IP address, increase metric value by M") |
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g.add_argument("--community", metavar="COMMUNITY", type=str, default=None, help="announce IPs with the supplied community") |
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g.add_argument("--extended-community", metavar="EXTENDEDCOMMUNITY", type=str, default=None, help="announce IPs with the supplied extended community") |
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g.add_argument("--large-community", metavar="LARGECOMMUNITY", type=str, default=None, help="announce IPs with the supplied large community") |
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g.add_argument("--disabled-community", metavar="DISABLEDCOMMUNITY", type=str, default=None, help="announce IPs with the supplied community when disabled") |
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g.add_argument("--as-path", metavar="ASPATH", type=str, default=None, help="announce IPs with the supplied as-path") |
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g.add_argument("--withdraw-on-down", action="store_true", help="Instead of increasing the metric on health failure, withdraw the route") |
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g = parser.add_argument_group("reporting") |
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g.add_argument("--execute", metavar='CMD', type=str, action="append", help="execute CMD on state change") |
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g.add_argument("--up-execute", metavar='CMD', type=str, action="append", help="execute CMD when the service becomes available") |
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g.add_argument("--down-execute", metavar='CMD', type=str, action="append", help="execute CMD when the service becomes unavailable") |
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g.add_argument("--disabled-execute", metavar='CMD', type=str, action="append", help="execute CMD when the service is disabled") |
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# fmt: on |
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def parse(): |
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"""Parse arguments""" |
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formatter = argparse.RawDescriptionHelpFormatter |
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parser = argparse.ArgumentParser(description=sys.modules[__name__].__doc__, formatter_class=formatter) |
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setargs(parser) |
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options = parser.parse_args() |
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if options.config is not None: |
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# A configuration file has been provided. Read each line and |
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# build an equivalent command line. |
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args = sum( |
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[ |
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"--{0}".format(l.strip()).split("=", 1) |
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for l in options.config.readlines() |
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if not l.strip().startswith("#") and l.strip() |
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], |
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[], |
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) |
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args = [x.strip() for x in args] |
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args.extend(sys.argv[1:]) |
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options = parser.parse_args(args) |
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return options |
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def setup_logging(debug, silent, name, syslog_facility, syslog): |
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"""Setup logger""" |
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def syslog_address(): |
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"""Return a sensible syslog address""" |
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if sys.platform == "darwin": |
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return "/var/run/syslog" |
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if sys.platform.startswith("freebsd"): |
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return "/var/run/log" |
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if sys.platform.startswith("netbsd"): |
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return "/var/run/log" |
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if sys.platform.startswith("linux"): |
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return "/dev/log" |
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raise EnvironmentError("Unable to guess syslog address for your " "platform, try to disable syslog") |
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logger.setLevel(debug and logging.DEBUG or logging.INFO) |
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enable_syslog = syslog and not debug |
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# To syslog |
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if enable_syslog: |
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facility = getattr(logging.handlers.SysLogHandler, "LOG_{0}".format(syslog_facility.upper())) |
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sh = logging.handlers.SysLogHandler(address=str(syslog_address()), facility=facility) |
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if name: |
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healthcheck_name = "healthcheck-{0}".format(name) |
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else: |
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healthcheck_name = "healthcheck" |
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sh.setFormatter(logging.Formatter("{0}[{1}]: %(message)s".format(healthcheck_name, os.getpid()))) |
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logger.addHandler(sh) |
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# To console |
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toconsole = hasattr(sys.stderr, "isatty") and sys.stderr.isatty() and not silent # pylint: disable=E1101 |
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if toconsole: |
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ch = logging.StreamHandler() |
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ch.setFormatter(logging.Formatter("%(levelname)s[%(name)s] %(message)s")) |
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logger.addHandler(ch) |
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def loopback_ips(label, label_only): |
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"""Retrieve loopback IP addresses""" |
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logger.debug("Retrieve loopback IP addresses") |
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addresses = [] |
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if sys.platform.startswith("linux"): |
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# Use "ip" (ifconfig is not able to see all addresses) |
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ipre = re.compile(r"^(?P<index>\d+):\s+(?P<name>\S+)\s+inet6?\s+" r"(?P<ip>[\da-f.:]+)/(?P<mask>\d+)\s+.*") |
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labelre = re.compile(r".*\s+lo:(?P<label>\S+).*") |
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cmd = subprocess.Popen("/sbin/ip -o address show dev lo".split(), shell=False, stdout=subprocess.PIPE) |
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else: |
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# Try with ifconfig |
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ipre = re.compile( |
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r"^inet6?\s+(alias\s+)?(?P<ip>[\da-f.:]+)\s+" |
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r"(?:netmask 0x(?P<netmask>[0-9a-f]+)|" |
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r"prefixlen (?P<mask>\d+)).*" |
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) |
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cmd = subprocess.Popen("/sbin/ifconfig lo0".split(), shell=False, stdout=subprocess.PIPE) |
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labelre = re.compile(r"") |
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for line in cmd.stdout: |
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line = line.decode("ascii", "ignore").strip() |
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mo = ipre.match(line) |
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if not mo: |
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continue |
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if mo.group("mask"): |
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mask = int(mo.group("mask")) |
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else: |
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mask = bin(int(mo.group("netmask"), 16)).count("1") |
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try: |
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ip = ip_network("{0}/{1}".format(mo.group("ip"), mask)) |
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except ValueError: |
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continue |
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if not ip.is_loopback: |
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if label: |
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lmo = labelre.match(line) |
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if not lmo: |
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continue |
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if lmo.groupdict().get("label", "").startswith(label): |
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addresses.append(ip) |
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elif not label_only: |
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addresses.append(ip) |
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logger.debug("Loopback addresses: %s", addresses) |
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return addresses |
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def loopback(): |
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lo = "lo0" |
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if sys.platform.startswith("linux"): |
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lo = "lo" |
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return lo |
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def setup_ips(ips, label, sudo=False): |
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"""Setup missing IP on loopback interface""" |
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existing = set(loopback_ips(label, False)) |
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toadd = set([ip_network(ip) for net in ips for ip in net]) - existing |
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for ip in toadd: |
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logger.debug("Setup loopback IP address %s", ip) |
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with open(os.devnull, "w") as fnull: |
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cmd = ["ip", "address", "add", str(ip), "dev", loopback()] |
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if sudo: |
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cmd.insert(0, "sudo") |
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if label: |
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cmd += ["label", "{0}:{1}".format(loopback(), label)] |
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try: |
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subprocess.check_call(cmd, stdout=fnull, stderr=fnull) |
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except subprocess.CalledProcessError as e: |
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# the IP address is already setup, ignoring |
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if cmd[0] == "ip" and cmd[2] == "add" and e.returncode == 2: |
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continue |
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raise e |
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def remove_ips(ips, label, sudo=False): |
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"""Remove added IP on loopback interface""" |
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existing = set(loopback_ips(label, True)) |
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# Get intersection of IPs (ips setup, and IPs configured by ExaBGP) |
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toremove = set([ip_network(ip) for net in ips for ip in net]) & existing |
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for ip in toremove: |
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logger.debug("Remove loopback IP address %s", ip) |
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with open(os.devnull, "w") as fnull: |
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cmd = ["ip", "address", "delete", str(ip), "dev", loopback()] |
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if sudo: |
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cmd.insert(0, "sudo") |
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if label: |
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cmd += ["label", "{0}:{1}".format(loopback(), label)] |
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try: |
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subprocess.check_call(cmd, stdout=fnull, stderr=fnull) |
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except subprocess.CalledProcessError: |
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logger.warn( |
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"Unable to remove loopback IP address %s - is \ |
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healthcheck running as root?", |
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str(ip), |
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) |
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def drop_privileges(user, group): |
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"""Drop privileges to specified user and group""" |
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if group is not None: |
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import grp |
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gid = grp.getgrnam(group).gr_gid |
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logger.debug("Dropping privileges to group {0}/{1}".format(group, gid)) |
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try: |
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os.setresgid(gid, gid, gid) |
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except AttributeError: |
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os.setregid(gid, gid) |
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if user is not None: |
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import pwd |
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uid = pwd.getpwnam(user).pw_uid |
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logger.debug("Dropping privileges to user {0}/{1}".format(user, uid)) |
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try: |
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os.setresuid(uid, uid, uid) |
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except AttributeError: |
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os.setreuid(uid, uid) |
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def check(cmd, timeout): |
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"""Check the return code of the given command. |
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:param cmd: command to execute. If :keyword:`None`, no command is executed. |
303
|
|
|
:param timeout: how much time we should wait for command completion. |
304
|
|
|
:return: :keyword:`True` if the command was successful or |
305
|
|
|
:keyword:`False` if not or if the timeout was triggered. |
306
|
|
|
""" |
307
|
|
|
if cmd is None: |
308
|
|
|
return True |
309
|
|
|
|
310
|
|
|
class Alarm(Exception): |
311
|
|
|
"""Exception to signal an alarm condition.""" |
312
|
|
|
|
313
|
|
|
pass |
314
|
|
|
|
315
|
|
|
def alarm_handler(number, frame): # pylint: disable=W0613 |
316
|
|
|
"""Handle SIGALRM signal.""" |
317
|
|
|
raise Alarm() |
|
|
|
|
318
|
|
|
|
319
|
|
|
logger.debug("Checking command %s", repr(cmd)) |
320
|
|
|
p = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, preexec_fn=os.setpgrp) |
321
|
|
|
if timeout: |
322
|
|
|
signal.signal(signal.SIGALRM, alarm_handler) |
323
|
|
|
signal.alarm(timeout) |
324
|
|
|
try: |
325
|
|
|
stdout = None |
326
|
|
|
stdout, _ = p.communicate() |
327
|
|
|
if timeout: |
328
|
|
|
signal.alarm(0) |
329
|
|
|
if p.returncode != 0: |
330
|
|
|
logger.warn("Check command was unsuccessful: %s", p.returncode) |
331
|
|
|
if stdout.strip(): |
332
|
|
|
logger.info("Output of check command: %s", stdout) |
333
|
|
|
return False |
334
|
|
|
logger.debug("Command was executed successfully %s %s", p.returncode, stdout) |
335
|
|
|
return True |
336
|
|
|
except Alarm: |
337
|
|
|
logger.warn("Timeout (%s) while running check command %s", timeout, cmd) |
338
|
|
|
os.killpg(p.pid, signal.SIGKILL) |
339
|
|
|
return False |
340
|
|
|
|
341
|
|
|
|
342
|
|
|
def loop(options): |
343
|
|
|
"""Main loop.""" |
344
|
|
|
states = enum( |
345
|
|
|
"INIT", # Initial state |
346
|
|
|
"DISABLED", # Disabled state |
347
|
|
|
"RISING", # Checks are currently succeeding. |
348
|
|
|
"FALLING", # Checks are currently failing. |
349
|
|
|
"UP", # Service is considered as up. |
350
|
|
|
"DOWN", # Service is considered as down. |
351
|
|
|
"EXIT", # Exit state |
352
|
|
|
"END", # End state, exiting but without removing loopback and/or announced routes |
353
|
|
|
) |
354
|
|
|
|
355
|
|
|
def exabgp(target): |
356
|
|
|
"""Communicate new state to ExaBGP""" |
357
|
|
|
if target not in (states.UP, states.DOWN, states.DISABLED, states.EXIT, states.END): |
358
|
|
|
return |
359
|
|
|
if target in (states.END,): |
360
|
|
|
return |
361
|
|
|
# dynamic ip management. When the service fail, remove the loopback |
362
|
|
|
if target in (states.EXIT,) and (options.ip_dynamic or options.ip_setup): |
363
|
|
|
logger.info("exiting, deleting loopback ips") |
364
|
|
|
remove_ips(options.ips, options.label, options.sudo) |
365
|
|
|
# dynamic ip management. When the service fail, remove the loopback |
366
|
|
|
if target in (states.DOWN, states.DISABLED) and options.ip_dynamic: |
367
|
|
|
logger.info("service down, deleting loopback ips") |
368
|
|
|
remove_ips(options.ips, options.label, options.sudo) |
369
|
|
|
# if ips was deleted with dyn ip, re-setup them |
370
|
|
|
if target == states.UP and options.ip_dynamic: |
371
|
|
|
logger.info("service up, restoring loopback ips") |
372
|
|
|
setup_ips(options.ips, options.label, options.sudo) |
373
|
|
|
|
374
|
|
|
logger.info("send announces for %s state to ExaBGP", target) |
375
|
|
|
metric = vars(options).get("{0}_metric".format(str(target).lower()), 0) |
376
|
|
|
for ip in options.ips: |
377
|
|
|
if options.withdraw_on_down or target is states.EXIT: |
378
|
|
|
command = "announce" if target is states.UP else "withdraw" |
379
|
|
|
else: |
380
|
|
|
command = "announce" |
381
|
|
|
announce = "route {0} next-hop {1}".format(str(ip), options.next_hop or "self") |
382
|
|
|
|
383
|
|
|
if command == "announce": |
384
|
|
|
announce = "{0} med {1}".format(announce, metric) |
385
|
|
|
if options.local_preference >= 0: |
386
|
|
|
announce = "{0} local-preference {1}".format(announce, options.local_preference) |
387
|
|
|
if options.community or options.disabled_community: |
388
|
|
|
community = options.community |
389
|
|
|
if target in (states.DOWN, states.DISABLED): |
390
|
|
|
if options.disabled_community: |
391
|
|
|
community = options.disabled_community |
392
|
|
|
if community: |
393
|
|
|
announce = "{0} community [ {1} ]".format(announce, community) |
394
|
|
|
if options.extended_community: |
395
|
|
|
announce = "{0} extended-community [ {1} ]".format(announce, options.extended_community) |
396
|
|
|
if options.large_community: |
397
|
|
|
announce = "{0} large-community [ {1} ]".format(announce, options.large_community) |
398
|
|
|
if options.as_path: |
399
|
|
|
announce = "{0} as-path [ {1} ]".format(announce, options.as_path) |
400
|
|
|
|
401
|
|
|
metric += options.increase |
402
|
|
|
|
403
|
|
|
# Send and flush command |
404
|
|
|
logger.debug("exabgp: {0} {1}".format(command, announce)) |
405
|
|
|
print("{0} {1}".format(command, announce)) |
406
|
|
|
sys.stdout.flush() |
407
|
|
|
|
408
|
|
|
# Wait for confirmation from ExaBGP if expected |
409
|
|
|
if options.no_ack: |
410
|
|
|
continue |
411
|
|
|
# if the program is not ran manually, do not read the input |
412
|
|
|
if hasattr(sys.stdout, "isatty") and sys.stdout.isatty(): |
413
|
|
|
continue |
414
|
|
|
sys.stdin.readline() |
415
|
|
|
|
416
|
|
|
def trigger(target): |
417
|
|
|
"""Trigger a state change and execute the appropriate commands""" |
418
|
|
|
# Shortcut for RISING->UP and FALLING->UP |
419
|
|
|
if target == states.RISING and options.rise <= 1: |
420
|
|
|
target = states.UP |
421
|
|
|
elif target == states.FALLING and options.fall <= 1: |
422
|
|
|
target = states.DOWN |
423
|
|
|
|
424
|
|
|
# Log and execute commands |
425
|
|
|
logger.debug("Transition to %s", str(target)) |
426
|
|
|
cmds = [] |
427
|
|
|
cmds.extend(vars(options).get("{0}_execute".format(str(target).lower()), []) or []) |
428
|
|
|
cmds.extend(vars(options).get("execute", []) or []) |
429
|
|
|
for cmd in cmds: |
430
|
|
|
logger.debug("Transition to %s, execute `%s`", str(target), cmd) |
431
|
|
|
env = os.environ.copy() |
432
|
|
|
env.update({"STATE": str(target)}) |
433
|
|
|
with open(os.devnull, "w") as fnull: |
434
|
|
|
subprocess.call(cmd, shell=True, stdout=fnull, stderr=fnull, env=env) |
435
|
|
|
|
436
|
|
|
return target |
437
|
|
|
|
438
|
|
|
def one(checks, state): |
439
|
|
|
"""Execute one loop iteration.""" |
440
|
|
|
disabled = options.disable is not None and os.path.exists(options.disable) |
441
|
|
|
successful = disabled or check(options.command, options.timeout) |
442
|
|
|
# FSM |
443
|
|
|
if state != states.DISABLED and disabled: |
444
|
|
|
state = trigger(states.DISABLED) |
445
|
|
|
elif state == states.INIT: |
446
|
|
|
if successful and options.rise <= 1: |
447
|
|
|
state = trigger(states.UP) |
448
|
|
|
elif successful: |
449
|
|
|
state = trigger(states.RISING) |
450
|
|
|
checks = 1 |
451
|
|
|
else: |
452
|
|
|
state = trigger(states.FALLING) |
453
|
|
|
checks = 1 |
454
|
|
|
elif state == states.DISABLED: |
455
|
|
|
if not disabled: |
456
|
|
|
state = trigger(states.INIT) |
457
|
|
|
elif state == states.RISING: |
458
|
|
|
if successful: |
459
|
|
|
checks += 1 |
460
|
|
|
if checks >= options.rise: |
461
|
|
|
state = trigger(states.UP) |
462
|
|
|
else: |
463
|
|
|
state = trigger(states.FALLING) |
464
|
|
|
checks = 1 |
465
|
|
|
elif state == states.FALLING: |
466
|
|
|
if not successful: |
467
|
|
|
checks += 1 |
468
|
|
|
if checks >= options.fall: |
469
|
|
|
state = trigger(states.DOWN) |
470
|
|
|
else: |
471
|
|
|
state = trigger(states.RISING) |
472
|
|
|
checks = 1 |
473
|
|
|
elif state == states.UP: |
474
|
|
|
if not successful: |
475
|
|
|
state = trigger(states.FALLING) |
476
|
|
|
checks = 1 |
477
|
|
|
elif state == states.DOWN: |
478
|
|
|
if successful: |
479
|
|
|
state = trigger(states.RISING) |
480
|
|
|
checks = 1 |
481
|
|
|
else: |
482
|
|
|
raise ValueError("Unhandled state: {0}".format(str(state))) |
483
|
|
|
|
484
|
|
|
# Send announces. We announce them on a regular basis in case |
485
|
|
|
# we lose connection with a peer and the adj-rib-out is disabled. |
486
|
|
|
exabgp(state) |
487
|
|
|
return checks, state |
488
|
|
|
|
489
|
|
|
checks = 0 |
490
|
|
|
state = states.INIT |
491
|
|
|
# Do cleanups on SIGTERM |
492
|
|
|
def sigterm_handler(signum, frame): # pylint: disable=W0612,W0613 |
493
|
|
|
exabgp(states.EXIT) |
494
|
|
|
sys.exit(0) |
495
|
|
|
|
496
|
|
|
signal.signal(signal.SIGTERM, sigterm_handler) |
497
|
|
|
|
498
|
|
|
while True: |
499
|
|
|
checks, state = one(checks, state) |
500
|
|
|
|
501
|
|
|
try: |
502
|
|
|
# How much we should sleep? |
503
|
|
|
if state in (states.FALLING, states.RISING): |
504
|
|
|
time.sleep(options.fast) |
505
|
|
|
elif options.interval == 0: |
506
|
|
|
logger.info("interval set to zero, exiting after the announcement") |
507
|
|
|
exabgp(states.END) |
508
|
|
|
break |
509
|
|
|
else: |
510
|
|
|
time.sleep(options.interval) |
511
|
|
|
except KeyboardInterrupt: |
512
|
|
|
exabgp(states.EXIT) |
513
|
|
|
break |
514
|
|
|
|
515
|
|
|
|
516
|
|
|
def cmdline(cmdarg): |
517
|
|
|
sys.argv = [f'{sys.argv[0]} {sys.argv[1]}'] + sys.argv[2:] |
518
|
|
|
main() |
519
|
|
|
|
520
|
|
|
|
521
|
|
|
def main(): |
522
|
|
|
"""Entry point.""" |
523
|
|
|
options = parse() |
524
|
|
|
setup_logging(options.debug, options.silent, options.name, options.syslog_facility, not options.no_syslog) |
525
|
|
|
if options.pid: |
526
|
|
|
options.pid.write("{0}\n".format(os.getpid())) |
527
|
|
|
options.pid.close() |
528
|
|
|
try: |
529
|
|
|
# Setup IP to use |
530
|
|
|
options.ips = options.ips or loopback_ips(options.label, False) |
531
|
|
|
if not options.ips: |
532
|
|
|
logger.error("No IP found") |
533
|
|
|
sys.exit(1) |
534
|
|
|
if options.ip_setup: |
535
|
|
|
setup_ips(options.ips, options.label, options.sudo) |
536
|
|
|
drop_privileges(options.user, options.group) |
537
|
|
|
|
538
|
|
|
# Parse defined networks into a list of IPs for advertisement |
539
|
|
|
if options.deaggregate_networks: |
540
|
|
|
options.ips = [ip_network(ip) for net in options.ips for ip in net] |
541
|
|
|
|
542
|
|
|
options.ips = collections.deque(options.ips) |
543
|
|
|
options.ips.rotate(-options.start_ip) |
544
|
|
|
options.ips = list(options.ips) |
545
|
|
|
# Main loop |
546
|
|
|
loop(options) |
547
|
|
|
except Exception as e: # pylint: disable=W0703 |
548
|
|
|
logger.exception("Uncaught exception: %s", e) |
549
|
|
|
sys.exit(1) |
550
|
|
|
|
551
|
|
|
|
552
|
|
|
if __name__ == "__main__": |
553
|
|
|
main() |
554
|
|
|
|