From 21c2154bedceb6ebef1cae369768280d4b0f8652 Mon Sep 17 00:00:00 2001

From: Marek 'marx' Grac <mgrac@redhat.com>

Date: Fri, 5 Jun 2015 18:07:55 +0200

Subject: [PATCH 2/4] fence_compute: Improvement of fence agent

---

 fence/agents/compute/fence_compute.py | 73 ++++++++++++++++++++++-------------

 fence/agents/lib/fencing.py.py        |  6 ++-

 2 files changed, 50 insertions(+), 29 deletions(-)

diff --git a/fence/agents/compute/fence_compute.py b/fence/agents/compute/fence_compute.py

index 2b37de7..66cf08f 100644

--- a/fence/agents/compute/fence_compute.py

+++ b/fence/agents/compute/fence_compute.py

@@ -4,11 +4,11 @@ import sys

 import time

 import atexit

 import logging

+import requests.exceptions

 sys.path.append("@FENCEAGENTSLIBDIR@")

 from fencing import *

 from fencing import fail_usage, is_executable, run_command, run_delay

-from novaclient import client as nova_client

 #BEGIN_VERSION_GENERATION

 RELEASE_VERSION="4.0.11"

@@ -32,18 +32,18 @@ def get_power_status(_, options):

 	if nova:

 		try:

 			services = nova.services.list(host=options["--plug"])

-		except Exception, e:

-			fail_usage(str(e))

-

-		for service in services:

-			if service.binary == "nova-compute":

-				if service.state == "up":

-					status = "on"

-				elif service.state == "down":

-					status = "down"

-				else:

-					logging.debug("Unknown status detected from nova: " + service.state)

-				break

+

+			for service in services:

+				if service.binary == "nova-compute":

+					if service.state == "up":

+						status = "on"

+					elif service.state == "down":

+						status = "off"

+					else:

+						logging.debug("Unknown status detected from nova: " + service.state)

+					break

+		except ConnectionError as (err):

+			logging.warning("Nova connection failed: " + str(err))

 	return status

 # NOTE(sbauza); We mimic the host-evacuate module since it's only a contrib

@@ -143,15 +143,6 @@ def define_new_opts():

 		"default" : "",

 		"order": 1,

 	}

-	all_opt["novatool-path"] = {

-		"getopt" : "i:",

-		"longopt" : "novatool-path",

-		"help" : "-i, --novatool-path=[path]     Path to nova binary",

-		"required" : "0",

-		"shortdesc" : "Path to nova binary",

-		"default" : "@NOVA_PATH@",

-		"order": 6,

-	}

 	all_opt["domain"] = {

 		"getopt" : "d:",

 		"longopt" : "domain",

@@ -177,7 +168,7 @@ def main():

 	atexit.register(atexit_handler)

 	device_opt = ["login", "passwd", "tenant-name", "auth-url",

-		"novatool-path", "no_login", "no_password", "port", "domain", "no-shared-storage"]

+		"no_login", "no_password", "port", "domain", "no-shared-storage"]

 	define_new_opts()

 	all_opt["shell_timeout"]["default"] = "180"

@@ -192,6 +183,15 @@ def main():

 	run_delay(options)

+	try:

+		from novaclient import client as nova_client

+	except ImportError:

+		fail_usage("nova not found or not accessible")

+

+	# Potentially we should make this a pacemaker feature

+	if options["--action"] != "list" and options["--domain"] != "" and options.has_key("--plug"):

+		options["--plug"] = options["--plug"] + "." + options["--domain"]

+

 	# The first argument is the Nova client version

 	nova = nova_client.Client('2',

 		options["--username"],

@@ -199,6 +199,29 @@ def main():

 		options["--tenant-name"],

 		options["--auth-url"])

+	if options["--action"] in ["on", "off", "reboot" ]:

+		try:

+			nova.services.list(host=options["--plug"])

+		except ConnectionError as (err):

+			# Yes, exit(0)

+			#

+			# Its possible that the control plane on which this

+			# agent depends is not functional

+			#

+			# In this situation, fencing is waiting for resource

+			# recovery and resource recovery is waiting for

+			# fencing.

+			#

+			# To break the cycle, we all the fencing agent to

+			# return 'done' immediately so that we can recover the

+			# control plane. We then rely on the NovaCompute RA

+			# to call this agent directly once the control plane

+			# is up.

+			#

+			# Yes its horrible, but still better than nova itself.

+			logging.warning("Nova connection failed: %s " % str(err))

+			sys.exit(0)

+

 	if options["--action"] in ["off", "reboot"]:

 		# Pretend we're 'on' so that the fencing library will always call set_power_status(off)

 		override_status = "on"

@@ -207,10 +230,6 @@ def main():

 		# Pretend we're 'off' so that the fencing library will always call set_power_status(on)

 		override_status = "off"

-	# Potentially we should make this a pacemaker feature

-	if options["--action"] != "list" and options["--domain"] != "" and options.has_key("--plug"):

-		options["--plug"] = options["--plug"]+"."+options["--domain"]

-

 	result = fence_action(None, options, set_power_status, get_power_status, get_plugs_list, None)

 	sys.exit(result)

diff --git a/fence/agents/lib/fencing.py.py b/fence/agents/lib/fencing.py.py

index f893082..29b3a94 100644

--- a/fence/agents/lib/fencing.py.py

+++ b/fence/agents/lib/fencing.py.py

@@ -1109,9 +1109,11 @@ def fence_login(options, re_login_string=r"(login\s*: )|(Login Name:  )|(usernam

 					conn.log_expect(options, options["--command-prompt"], int(options["--login-timeout"]))

 			except KeyError:

 				fail(EC_PASSWORD_MISSING)

-	except pexpect.EOF:

+	except pexpect.EOF, exception:

+		logging.debug("%s", str(exception))

 		fail(EC_LOGIN_DENIED)

-	except pexpect.TIMEOUT:

+	except pexpect.TIMEOUT, exception:

+		logging.debug("%s", str(exception))

 		fail(EC_LOGIN_DENIED)

 	return conn

-- 

1.9.3