def test_leaving(self, client):
"""Create a plugin not in the cluster and try to leave the cluster.
Nothing should be written to etcd."""
e = EtcdSynchronizer(self.plugin, self.watcher_ip)
e.start_thread()
e.leave_cluster()
e._client.write.assert_not_called()
e.terminate()
def test_mark_failed(self, client):
"""Create a plugin not in the cluster and try to mark it as failed.
Nothing should be written to etcd."""
e = EtcdSynchronizer(self.plugin, self.watcher_ip)
e.start_thread()
e.mark_node_failed()
e._client.write.assert_not_called()
e.terminate()
def test_scale_up(self):
# Create an existing cluster of two nodes, and a third new node
sync1 = EtcdSynchronizer(DummyPlugin(None), '10.0.0.1')
sync2 = EtcdSynchronizer(DummyPlugin(None), '10.0.0.2')
sync3 = EtcdSynchronizer(DummyPlugin(None), '10.0.0.3')
mock_client = sync1._client
mock_client.write(
"/test", json.dumps({
"10.0.0.1": "normal",
"10.0.0.2": "normal"
}))
for s in [sync1, sync2, sync3]:
s.start_thread()
# Check that the third node joins the cluster
self.wait_for_all_normal(mock_client, required_number=3)
end = json.loads(mock_client.read("/test").value)
self.assertEqual("normal", end.get("10.0.0.3"))
for s in [sync1, sync2, sync3]:
s.terminate()
def test_mark_failed(self, client):
"""Create a plugin not in the cluster and try to mark it as failed.
Nothing should be written to etcd."""
e = EtcdSynchronizer(self.plugin, self.watcher_ip)
e.start_thread()
e.mark_node_failed()
e._client.write.assert_not_called()
e.terminate()
def test_leaving(self, client):
"""Create a plugin not in the cluster and try to leave the cluster.
Nothing should be written to etcd."""
e = EtcdSynchronizer(self.plugin, self.watcher_ip)
e.start_thread()
e.leave_cluster()
e._client.write.assert_not_called()
e.terminate()
def test_watcher(self):
"""Create a new 3-node cluster with one plugin not in the cluster and
check that the main three all end up in NORMAL state"""
e = EtcdSynchronizer(self.plugin, self.watcher_ip)
e.start_thread()
self.make_and_start_synchronizers(3)
mock_client = self.syncs[0]._client
self.wait_for_all_normal(mock_client, required_number=3)
# Pause for one second - the watcher plugin might be called just after
# all other nodes enter 'normal' state
sleep(1)
self.assertTrue(self.plugin.on_stable_cluster_called)
end = json.loads(mock_client.read("/test").value)
self.assertEqual("normal", end.get("10.0.0.0"))
self.assertEqual("normal", end.get("10.0.0.1"))
self.assertEqual("normal", end.get("10.0.0.2"))
self.assertEqual(None, end.get("10.1.1.1"))
e.terminate()
def test_failure(self):
# Create synchronisers, using a FailPlugin for one which will crash and
# not complete (simulating a failed node)
sync1 = EtcdSynchronizer(DummyPlugin(None), '10.0.0.1')
sync2 = EtcdSynchronizer(FailPlugin(None), '10.0.0.2')
sync3 = EtcdSynchronizer(DummyPlugin(None), '10.0.0.3')
mock_client = sync1._client
for s in [sync1, sync2, sync3]:
s.start_thread()
# After a few seconds, the scale-up will still not have completed
sleep(3)
end = json.loads(mock_client.read("/test").value)
self.assertNotEqual("normal", end.get("10.0.0.1"))
self.assertNotEqual("normal", end.get("10.0.0.2"))
self.assertNotEqual("normal", end.get("10.0.0.3"))
# Start a synchroniser to take 10.0.0.2's place
sync2.terminate()
error_syncer = EtcdSynchronizer(NullPlugin('/test'),
'10.0.0.2',
force_leave=True)
error_syncer.mark_node_failed()
error_syncer.leave_cluster()
error_syncer.start_thread()
# 10.0.0.2 will be removed from the cluster, and the cluster will
# stabilise
self.wait_for_all_normal(mock_client, required_number=2, tries=50)
end = json.loads(mock_client.read("/test").value)
self.assertEqual("normal", end.get("10.0.0.1"))
self.assertEqual("normal", end.get("10.0.0.3"))
self.assertEqual(None, end.get("10.0.0.2"))
for s in [sync1, sync3, error_syncer]:
s.terminate()
def test_scale_down(self):
# Start with a stable cluster of two nodes
sync1 = EtcdSynchronizer(DummyPlugin(None), '10.0.1.1')
sync2 = EtcdSynchronizer(DummyPlugin(None), '10.0.1.2')
mock_client = sync1._client
mock_client.write("/test", json.dumps({"10.0.1.1": "normal",
"10.0.1.2": "normal"}))
for s in [sync1, sync2]:
s.start_thread()
# Make the second node leave
sync2.leave_cluster()
sync2.thread.join(20)
sync2.terminate()
self.wait_for_all_normal(mock_client, required_number=1)
# Check that it's left and the cluster is stable
end = json.loads(mock_client.read("/test").value)
self.assertEqual(None, end.get("10.0.1.2"))
self.assertEqual("normal", end.get("10.0.1.1"))
sync1.terminate()
def test_scale_down(self):
# Start with a stable cluster of four nodes
syncs = [
EtcdSynchronizer(DummyPlugin(None), ip) for ip in [
'10.0.1.1',
'10.0.1.2',
'10.0.1.3',
'10.0.1.4',
]
]
mock_client = syncs[0]._client
mock_client.write(
"/test",
json.dumps({
"10.0.1.1": "normal",
"10.0.1.2": "normal",
"10.0.1.3": "normal",
"10.0.1.4": "normal",
}))
for s in syncs:
s.start_thread()
# Allow the cluster to stabilise, then make the second and fourth nodes leave
sleep(1)
syncs[1].leave_cluster()
syncs[3].leave_cluster()
self.wait_for_all_normal(mock_client, required_number=2, tries=50)
# Check that it's left and the cluster is stable
end = json.loads(mock_client.read("/test").value)
self.assertEqual("normal", end.get("10.0.1.1"))
self.assertEqual("normal", end.get("10.0.1.3"))
self.assertEqual(None, end.get("10.0.1.2"))
self.assertEqual(None, end.get("10.0.1.4"))
for s in syncs:
s.terminate()
def test_watcher(self):
"""Create a new 3-node cluster with one plugin not in the cluster and
check that the main three all end up in NORMAL state"""
e = EtcdSynchronizer(self.plugin, self.watcher_ip)
e.start_thread()
self.make_and_start_synchronizers(3)
mock_client = self.syncs[0]._client
self.wait_for_all_normal(mock_client, required_number=3)
# Pause for one second - the watcher plugin might be called just after
# all other nodes enter 'normal' state
sleep(1)
self.assertTrue(self.plugin.on_stable_cluster_called)
end = json.loads(mock_client.read("/test").value)
self.assertEqual("normal", end.get("10.0.0.0"))
self.assertEqual("normal", end.get("10.0.0.1"))
self.assertEqual("normal", end.get("10.0.0.2"))
self.assertEqual(None, end.get("10.1.1.1"))
e.terminate()
def main(args):
syslog.openlog("cluster-manager", syslog.LOG_PID)
pdlogs.STARTUP.log()
try:
arguments = docopt(__doc__, argv=args)
except DocoptExit:
pdlogs.EXITING_BAD_CONFIG.log()
raise
mgmt_ip = arguments['--mgmt-local-ip']
sig_ip = arguments['--sig-local-ip']
local_site_name = arguments['--local-site']
remote_site_name = arguments['--remote-site']
signaling_namespace = arguments.get('--signaling-namespace')
log_dir = arguments['--log-directory']
log_level = LOG_LEVELS.get(arguments['--log-level'], logging.DEBUG)
stdout_err_log = os.path.join(log_dir, "cluster-manager.output.log")
if not arguments['--foreground']:
utils.daemonize(stdout_err_log)
logging_config.configure_logging(log_level, log_dir, "cluster-manager", show_thread=True)
# urllib3 logs a WARNING log whenever it recreates a connection, but our
# etcd usage does this frequently (to allow watch timeouts), so deliberately
# ignore this log
urllib_logger = logging.getLogger('urllib3')
urllib_logger.setLevel(logging.ERROR)
utils.install_sigusr1_handler("cluster-manager")
# Drop a pidfile.
pid = os.getpid()
with open(arguments['--pidfile'], "w") as pidfile:
pidfile.write(str(pid) + "\n")
plugins_dir = "/usr/share/clearwater/clearwater-cluster-manager/plugins/"
plugins = load_plugins_in_dir(plugins_dir,
PluginParams(ip=sig_ip,
mgmt_ip=mgmt_ip,
local_site=local_site_name,
remote_site=remote_site_name,
signaling_namespace=signaling_namespace))
plugins.sort(key=lambda x: x.key())
plugins_to_use = []
files = []
skip = False
for plugin in plugins:
for plugin_file in plugin.files():
if plugin_file in files:
_log.info("Skipping plugin {} because {} "
"is already managed by another plugin"
.format(plugin, plugin_file))
skip = True
if not skip:
plugins_to_use.append(plugin)
files.extend(plugin.files())
synchronizers = []
threads = []
for plugin in plugins_to_use:
syncer = EtcdSynchronizer(plugin, sig_ip, etcd_ip=mgmt_ip)
syncer.start_thread()
synchronizers.append(syncer)
threads.append(syncer.thread)
_log.info("Loaded plugin %s" % plugin)
install_sigquit_handler(synchronizers)
install_sigterm_handler(synchronizers)
while any([thread.isAlive() for thread in threads]):
for thread in threads:
if thread.isAlive():
thread.join(1)
_log.info("No plugin threads running, waiting for a SIGTERM or SIGQUIT")
while not should_quit:
sleep(1)
_log.info("Quitting")
_log.debug("%d threads outstanding at exit" % activeCount())
pdlogs.EXITING.log()
syslog.closelog()
# Use os.exit to skip exit handlers - otherwise the concurrent.futures exit
# handler waits for an infinite wait to end
os._exit(0)
node_type = sys.argv[3]
datastore = sys.argv[4]
dead_node_ip = sys.argv[5]
etcd_key = sys.argv[6]
key = make_key(site, node_type, datastore, etcd_key)
_log.info("Using etcd key %s" % (key))
if datastore == "cassandra":
try:
sys.path.append(
"/usr/share/clearwater/clearwater-cluster-manager/failed_plugins")
from cassandra_failed_plugin import CassandraFailedPlugin
error_syncer = EtcdSynchronizer(CassandraFailedPlugin(
key, dead_node_ip),
dead_node_ip,
etcd_ip=etcd_ip,
force_leave=True)
except ImportError:
print "You must run mark_node_failed on a node that has Cassandra installed to remove a node from a Cassandra cluster"
sys.exit(1)
else:
error_syncer = EtcdSynchronizer(NullPlugin(key),
dead_node_ip,
etcd_ip=etcd_ip,
force_leave=True)
# Check that the dead node is even a member of the cluster
etcd_result, idx = error_syncer.read_from_etcd(wait=False, timeout=10)
if etcd_result is None:
def main(args):
syslog.openlog("cluster-manager", syslog.LOG_PID)
pdlogs.STARTUP.log()
try:
arguments = docopt(__doc__, argv=args)
except DocoptExit:
pdlogs.EXITING_BAD_CONFIG.log()
raise
mgmt_ip = arguments['--mgmt-local-ip']
sig_ip = arguments['--sig-local-ip']
local_site_name = arguments['--local-site']
remote_site_name = arguments['--remote-site']
remote_cassandra_seeds = arguments['--remote-cassandra-seeds']
if remote_cassandra_seeds:
remote_cassandra_seeds = remote_cassandra_seeds.split(',')
else:
remote_cassandra_seeds = []
signaling_namespace = arguments.get('--signaling-namespace')
local_uuid = UUID(arguments['--uuid'])
etcd_key = arguments.get('--etcd-key')
etcd_cluster_key = arguments.get('--etcd-cluster-key')
cluster_manager_enabled = arguments['--cluster-manager-enabled']
log_dir = arguments['--log-directory']
log_level = LOG_LEVELS.get(arguments['--log-level'], logging.DEBUG)
stdout_err_log = os.path.join(log_dir, "cluster-manager.output.log")
# Check that there's an etcd_cluster_key value passed to the cluster
# manager
if etcd_cluster_key == "":
# The etcd_cluster_key isn't valid, and possibly get weird entries in
# the etcd database if we allow the cluster_manager to start
pdlogs.EXITING_MISSING_ETCD_CLUSTER_KEY.log()
exit(1)
if not arguments['--foreground']:
utils.daemonize(stdout_err_log)
# Process names are limited to 15 characters, so abbreviate
prctl.prctl(prctl.NAME, "cw-cluster-mgr")
logging_config.configure_logging(log_level, log_dir, "cluster-manager", show_thread=True)
# urllib3 logs a WARNING log whenever it recreates a connection, but our
# etcd usage does this frequently (to allow watch timeouts), so deliberately
# ignore this log
urllib_logger = logging.getLogger('urllib3')
urllib_logger.setLevel(logging.ERROR)
utils.install_sigusr1_handler("cluster-manager")
# Drop a pidfile. We must keep a reference to the file object here, as this keeps
# the file locked and provides extra protection against two processes running at
# once.
pidfile_lock = None
try:
pidfile_lock = utils.lock_and_write_pid_file(arguments['--pidfile']) # noqa
except IOError:
# We failed to take the lock - another process is already running
exit(1)
plugins_dir = "/usr/share/clearwater/clearwater-cluster-manager/plugins/"
plugins = load_plugins_in_dir(plugins_dir,
PluginParams(ip=sig_ip,
mgmt_ip=mgmt_ip,
local_site=local_site_name,
remote_site=remote_site_name,
remote_cassandra_seeds=remote_cassandra_seeds,
signaling_namespace=signaling_namespace,
uuid=local_uuid,
etcd_key=etcd_key,
etcd_cluster_key=etcd_cluster_key))
plugins.sort(key=lambda x: x.key())
plugins_to_use = []
files = []
skip = False
for plugin in plugins:
for plugin_file in plugin.files():
if plugin_file in files:
_log.info("Skipping plugin {} because {} "
"is already managed by another plugin"
.format(plugin, plugin_file))
skip = True
if not skip:
plugins_to_use.append(plugin)
files.extend(plugin.files())
synchronizers = []
threads = []
if cluster_manager_enabled == "N":
# Don't start any threads as we don't want the cluster manager to run
pdlogs.DO_NOT_START.log()
elif etcd_cluster_key == "DO_NOT_CLUSTER":
# Don't start any threads as we don't want this box to cluster
pdlogs.DO_NOT_CLUSTER.log()
else:
for plugin in plugins_to_use:
syncer = EtcdSynchronizer(plugin, sig_ip, etcd_ip=mgmt_ip)
syncer.start_thread()
synchronizers.append(syncer)
threads.append(syncer.thread)
_log.info("Loaded plugin %s" % plugin)
install_sigquit_handler(synchronizers)
utils.install_sigterm_handler(synchronizers)
while any([thread.isAlive() for thread in threads]):
for thread in threads:
if thread.isAlive():
thread.join(1)
_log.info("No plugin threads running, waiting for a SIGTERM or SIGQUIT")
while not utils.should_quit and not should_quit:
sleep(1)
_log.info("Quitting")
_log.debug("%d threads outstanding at exit" % activeCount())
pdlogs.EXITING.log()
syslog.closelog()
logfile = "/var/log/clearwater-etcd/mark_node_failed.log"
print "Detailed output being sent to %s" % logfile
logging.basicConfig(filename=logfile,
format='%(asctime)s - %(name)s - %(levelname)s - %(message)s',
level=logging.DEBUG)
local_ip = sys.argv[1]
site = sys.argv[2]
node_type = sys.argv[3]
datastore = sys.argv[4]
dead_node_ip = sys.argv[5]
key = make_key(site, node_type, datastore)
logging.info("Using etcd key %s" % (key))
error_syncer = EtcdSynchronizer(NullPlugin(key), dead_node_ip, etcd_ip=local_ip, force_leave=True)
print "Marking node as failed and removing it from the cluster - will take at least 30 seconds"
# Move the dead node into ERROR state to allow in-progress operations to
# complete
error_syncer.mark_node_failed()
# Move the dead node out of the cluster
error_syncer.start_thread()
error_syncer.leave_cluster()
# Wait for it to leave
error_syncer.thread.join()
print "Process complete - %s has left the cluster" % dead_node_ip
c = etcd.Client(local_ip, 4000)
def main(args):
syslog.openlog("cluster-manager", syslog.LOG_PID)
pdlogs.STARTUP.log()
try:
arguments = docopt(__doc__, argv=args)
except DocoptExit:
pdlogs.EXITING_BAD_CONFIG.log()
raise
mgmt_ip = arguments['--mgmt-local-ip']
sig_ip = arguments['--sig-local-ip']
local_site_name = arguments['--local-site']
remote_site_name = arguments['--remote-site']
remote_cassandra_seeds = arguments['--remote-cassandra-seeds']
if remote_cassandra_seeds:
remote_cassandra_seeds = remote_cassandra_seeds.split(',')
else:
remote_cassandra_seeds = []
signaling_namespace = arguments.get('--signaling-namespace')
local_uuid = UUID(arguments['--uuid'])
etcd_key = arguments.get('--etcd-key')
etcd_cluster_key = arguments.get('--etcd-cluster-key')
cluster_manager_enabled = arguments['--cluster-manager-enabled']
log_dir = arguments['--log-directory']
log_level = LOG_LEVELS.get(arguments['--log-level'], logging.DEBUG)
stdout_err_log = os.path.join(log_dir, "cluster-manager.output.log")
# Check that there's an etcd_cluster_key value passed to the cluster
# manager
if etcd_cluster_key == "":
# The etcd_cluster_key isn't valid, and possibly get weird entries in
# the etcd database if we allow the cluster_manager to start
pdlogs.EXITING_MISSING_ETCD_CLUSTER_KEY.log()
exit(1)
if not arguments['--foreground']:
utils.daemonize(stdout_err_log)
# Process names are limited to 15 characters, so abbreviate
prctl.prctl(prctl.NAME, "cw-cluster-mgr")
logging_config.configure_logging(log_level,
log_dir,
"cluster-manager",
show_thread=True)
# urllib3 logs a WARNING log whenever it recreates a connection, but our
# etcd usage does this frequently (to allow watch timeouts), so deliberately
# ignore this log
urllib_logger = logging.getLogger('urllib3')
urllib_logger.setLevel(logging.ERROR)
utils.install_sigusr1_handler("cluster-manager")
# Drop a pidfile. We must keep a reference to the file object here, as this keeps
# the file locked and provides extra protection against two processes running at
# once.
pidfile_lock = None
try:
pidfile_lock = utils.lock_and_write_pid_file(
arguments['--pidfile']) # noqa
except IOError:
# We failed to take the lock - another process is already running
exit(1)
plugins_dir = "/usr/share/clearwater/clearwater-cluster-manager/plugins/"
plugins = load_plugins_in_dir(
plugins_dir,
PluginParams(ip=sig_ip,
mgmt_ip=mgmt_ip,
local_site=local_site_name,
remote_site=remote_site_name,
remote_cassandra_seeds=remote_cassandra_seeds,
signaling_namespace=signaling_namespace,
uuid=local_uuid,
etcd_key=etcd_key,
etcd_cluster_key=etcd_cluster_key))
plugins.sort(key=lambda x: x.key())
plugins_to_use = []
files = []
skip = False
for plugin in plugins:
for plugin_file in plugin.files():
if plugin_file in files:
_log.info("Skipping plugin {} because {} "
"is already managed by another plugin".format(
plugin, plugin_file))
skip = True
if not skip:
plugins_to_use.append(plugin)
files.extend(plugin.files())
synchronizers = []
threads = []
if cluster_manager_enabled == "N":
# Don't start any threads as we don't want the cluster manager to run
pdlogs.DO_NOT_START.log()
elif etcd_cluster_key == "DO_NOT_CLUSTER":
# Don't start any threads as we don't want this box to cluster
pdlogs.DO_NOT_CLUSTER.log()
else:
for plugin in plugins_to_use:
syncer = EtcdSynchronizer(plugin, sig_ip, etcd_ip=mgmt_ip)
syncer.start_thread()
synchronizers.append(syncer)
threads.append(syncer.thread)
_log.info("Loaded plugin %s" % plugin)
install_sigquit_handler(synchronizers)
install_sigterm_handler(synchronizers)
while any([thread.isAlive() for thread in threads]):
for thread in threads:
if thread.isAlive():
thread.join(1)
_log.info("No plugin threads running, waiting for a SIGTERM or SIGQUIT")
while not should_quit:
sleep(1)
_log.info("Quitting")
_log.debug("%d threads outstanding at exit" % activeCount())
pdlogs.EXITING.log()
syslog.closelog()
def test_failure(self):
# Create synchronisers, using a FailPlugin for one which will crash and
# not complete (simulating a failed node)
sync1 = EtcdSynchronizer(DummyPlugin(None), '10.0.0.1')
sync2 = EtcdSynchronizer(FailPlugin(None), '10.0.0.2')
sync3 = EtcdSynchronizer(DummyPlugin(None), '10.0.0.3')
mock_client = sync1._client
for s in [sync1, sync2, sync3]:
s.start_thread()
# After a few seconds, the scale-up will still not have completed
sleep(3)
end = json.loads(mock_client.read("/test").value)
self.assertNotEqual("normal", end.get("10.0.0.1"))
self.assertNotEqual("normal", end.get("10.0.0.2"))
self.assertNotEqual("normal", end.get("10.0.0.3"))
# Start a synchroniser to take 10.0.0.2's place
sync2.terminate()
error_syncer = EtcdSynchronizer(NullPlugin('/test'),
'10.0.0.2',
force_leave=True)
error_syncer.mark_node_failed()
error_syncer.leave_cluster()
error_syncer.start_thread()
# 10.0.0.2 will be removed from the cluster, and the cluster will
# stabilise
self.wait_for_all_normal(mock_client, required_number=2, tries=50)
end = json.loads(mock_client.read("/test").value)
self.assertEqual("normal", end.get("10.0.0.1"))
self.assertEqual("normal", end.get("10.0.0.3"))
self.assertEqual(None, end.get("10.0.0.2"))
for s in [sync1, sync3, error_syncer]:
s.terminate()
node_type = sys.argv[3]
datastore = sys.argv[4]
dead_node_ip = sys.argv[5]
etcd_key = sys.argv[6]
key = make_key(site, node_type, datastore, etcd_key)
logging.info("Using etcd key %s" % (key))
if datastore == "cassandra":
try:
sys.path.append(
"/usr/share/clearwater/clearwater-cluster-manager/failed_plugins")
from cassandra_failed_plugin import CassandraFailedPlugin
error_syncer = EtcdSynchronizer(CassandraFailedPlugin(
key, dead_node_ip),
dead_node_ip,
etcd_ip=local_ip,
force_leave=True)
except ImportError:
print "You must run mark_node_failed on a node that has Cassandra installed to remove a node from a Cassandra cluster"
sys.exit(1)
else:
error_syncer = EtcdSynchronizer(NullPlugin(key),
dead_node_ip,
etcd_ip=local_ip,
force_leave=True)
print "Marking node as failed and removing it from the cluster - will take at least 30 seconds"
# Move the dead node into ERROR state to allow in-progress operations to
# complete
error_syncer.mark_node_failed()
def make_and_start_synchronizers(self, num, klass=DummyPlugin):
ips = ["10.0.0.%s" % d for d in range(num)]
self.syncs = [EtcdSynchronizer(klass(ip), ip) for ip in ips]
for s in self.syncs:
s.start_thread()
sleep(1) # Allow cluster to stabilise
etcd_ip = sys.argv[1]
site = sys.argv[2]
node_type = sys.argv[3]
datastore = sys.argv[4]
dead_node_ip = sys.argv[5]
etcd_key = sys.argv[6]
key = make_key(site, node_type, datastore, etcd_key)
_log.info("Using etcd key %s" % (key))
if datastore == "cassandra":
try:
sys.path.append("/usr/share/clearwater/clearwater-cluster-manager/failed_plugins")
from cassandra_failed_plugin import CassandraFailedPlugin
error_syncer = EtcdSynchronizer(CassandraFailedPlugin(key, dead_node_ip), dead_node_ip, etcd_ip=etcd_ip, force_leave=True)
except ImportError:
print "You must run mark_node_failed on a node that has Cassandra installed to remove a node from a Cassandra cluster"
sys.exit(1)
else:
error_syncer = EtcdSynchronizer(NullPlugin(key), dead_node_ip, etcd_ip=etcd_ip, force_leave=True)
# Check that the dead node is even a member of the cluster
etcd_result, idx = error_syncer.read_from_etcd(wait=False, timeout=10)
if etcd_result is None:
print "Failed to contact etcd cluster on '{}' - node not removed".format(etcd_ip)
sys.exit(1)
cluster_info = ClusterInfo(etcd_result)