Page MenuHomeClusterLabs Projects
Files F4832605

fence_crosslink.py
No OneTemporary
Actions

fence_crosslink.py
View Options

#!@PYTHON@ -tt
# Copyright (c) 2020 Red Hat
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library. If not, see
# <http://www.gnu.org/licenses/>.
import atexit
import logging
import sys
sys.path.append("@FENCEAGENTSLIBDIR@")
from fencing import (all_opt, atexit_handler, check_input, # noqa: E402
fence_action, process_input, run_command, run_delay,
show_docs)
logger = logging.getLogger(__name__)
logger.setLevel("WARNING")
def get_power_status(conn, options):
logger.debug("get_power_status(): %s" % options)
ip = options['--crosscableip']
timeout = options['--timeout']
# This returns 'off' if not a single ICMP packet gets answered during the
# whole timeout window. (the ping executable will return 1 in such case and
# 0 if even a single packet gets replied to)
(status, stdout, stderr) = run_command(options, "ping -w%s -n %s" %
(timeout, ip))
logger.debug("get_power_status(): %s - Stdout: %s - Stderr: %s" %
(status, stdout, stderr))
if status == 0:
return "on"
else:
return "off"
def set_power_status(conn, options):
logger.debug("set_power_status(): %s" % options)
# If we got here it means the previous call to get_power_status() returned
# on At this point we've been invoked but the node is still reachable over
# the cross connect, so we can just error out.
ip = options['--crosscableip']
if options['--action'] == 'off':
logger.error("We've been asked to turn off the node at %s but the "
"cross-cable link is up so erroring out" % ip)
sys.exit(1)
elif options['--action'] == 'on':
logger.error("We've been asked to turn on the node at %s but the "
"cross-cable link is off so erroring out" % ip)
sys.exit(1)
else:
logger.error("set_power_status() was called with action %s which "
"is not supported" % options['--action'])
sys.exit(1)
def define_new_opts():
all_opt["crosscableip"] = {
"getopt": "a:",
"longopt": "crosscableip",
"help": "-a, --crosscableip=[IP] IP over the cross-cable link",
"required": "1",
"shortdesc": "Cross-cable IP",
"order": 1
}
all_opt["timeout"] = {
"getopt": "T:",
"longopt": "timeout",
"help": "-T, --timeout=[seconds] timeout in seconds",
"required": "0",
"shortdesc": "No ICMP reply in 5 seconds -> Node is considered dead",
"default": "5",
"order": 1
}
def main():
atexit.register(atexit_handler)
device_opt = ["crosscableip", "timeout", "no_password", "no_login", "port"]
define_new_opts()
options = check_input(device_opt, process_input(device_opt))
docs = {}
docs["shortdesc"] = "Fence agent for cross-link two-node clusters"
docs["longdesc"] = "This agent helps two-node clusters to tackle the " \
"situation where one node lost power, cannot be " \
"fenced by telling pacemaker that if the node is not " \
"reachable over the crosslink cable, we can assume " \
"it is dead"
docs["vendorurl"] = ""
show_docs(options, docs)
run_delay(options)
result = fence_action(None, options, set_power_status, get_power_status)
sys.exit(result)
if __name__ == "__main__":
main()

File Metadata

Mime Type
text/x-script.python
Expires
Sun, Jul 20, 7:49 PM (3 h, 43 m)
Storage Engine
blob
Storage Format
Raw Data
Storage Handle
2066497
Default Alt Text
fence_crosslink.py (3 KB)

Event Timeline