From 12848c286008ef850bedb4552d4a8778f3164b00 Mon Sep 17 00:00:00 2001

From: Mohammed Gamal <mgamal@redhat.com>

Date: Thu, 2 Jun 2022 14:39:42 +0200

Subject: [PATCH] Fix if hangs (#2283)

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2092753

Signed-off-by: Laveesh Rohra <larohra@microsoft.com>

(cherry picked from commit 05cd6437ba90928788ef18c8b9fc8a6dbaf47c7d)

Signed-off-by: Mohammed Gamal <mgamal@redhat.com>

---

 azurelinuxagent/common/osutil/default.py | 26 ++++++++----------------

 azurelinuxagent/common/osutil/ubuntu.py  | 22 +++++++++-----------

 tests/common/osutil/test_default.py      | 11 +++-------

 3 files changed, 21 insertions(+), 38 deletions(-)

diff --git a/azurelinuxagent/common/osutil/default.py b/azurelinuxagent/common/osutil/default.py

index 066e1431..820016c1 100644

--- a/azurelinuxagent/common/osutil/default.py

+++ b/azurelinuxagent/common/osutil/default.py

@@ -1163,25 +1163,15 @@ class DefaultOSUtil(object):

     def restart_if(self, ifname, retries=3, wait=5):

         retry_limit = retries + 1

         for attempt in range(1, retry_limit):

-            try:

-                shellutil.run_command(["ifdown", ifname])

-                shellutil.run_command(["ifup", ifname])

+            return_code = shellutil.run("ifdown {0} && ifup {0}".format(ifname), expected_errors=[1] if attempt < retries else [])

+            if return_code == 0:

                 return

-            except shellutil.CommandError as cmd_err:

-                

-                msg = "failed to restart {0}: returncode={1}\n[stdout]{2}\n\n[stderr]{3}\n"\

-                    .format(ifname, cmd_err.returncode, cmd_err.stdout, cmd_err.stderr)

-                

-                if cmd_err.returncode == 1:

-                    logger.info(msg)

-                else:

-                    logger.warn(msg)

-

-                if attempt < retry_limit:

-                    logger.info("retrying in {0} seconds".format(wait))

-                    time.sleep(wait)

-                else:

-                    logger.warn("exceeded restart retries")

+            logger.warn("failed to restart {0}: return code {1}".format(ifname, return_code))

+            if attempt < retry_limit:

+                logger.info("retrying in {0} seconds".format(wait))

+                time.sleep(wait)

+            else:

+                logger.warn("exceeded restart retries")

     def publish_hostname(self, hostname):

         self.set_dhcp_hostname(hostname)

diff --git a/azurelinuxagent/common/osutil/ubuntu.py b/azurelinuxagent/common/osutil/ubuntu.py

index 249e1120..5a21511c 100644

--- a/azurelinuxagent/common/osutil/ubuntu.py

+++ b/azurelinuxagent/common/osutil/ubuntu.py

@@ -142,19 +142,17 @@ class UbuntuOSUtil(Ubuntu16OSUtil):

         Restart an interface by bouncing the link. systemd-networkd observes

         this event, and forces a renew of DHCP.

         """

-        retry_limit=retries+1

+        retry_limit = retries+1

         for attempt in range(1, retry_limit):

-            try:

-                shellutil.run_command(["ip", "link", "set", ifname, "down"])

-                shellutil.run_command(["ip", "link", "set", ifname, "up"])

-

-            except shellutil.CommandError as cmd_err:

-                logger.warn("failed to restart {0}: return code {1}".format(ifname, cmd_err.returncode))

-                if attempt < retry_limit:

-                    logger.info("retrying in {0} seconds".format(wait))

-                    time.sleep(wait)

-                else:

-                    logger.warn("exceeded restart retries")

+            return_code = shellutil.run("ip link set {0} down && ip link set {0} up".format(ifname))

+            if return_code == 0:

+                return

+            logger.warn("failed to restart {0}: return code {1}".format(ifname, return_code))

+            if attempt < retry_limit:

+                logger.info("retrying in {0} seconds".format(wait))

+                time.sleep(wait)

+            else:

+                logger.warn("exceeded restart retries")

 class UbuntuSnappyOSUtil(Ubuntu14OSUtil):

diff --git a/tests/common/osutil/test_default.py b/tests/common/osutil/test_default.py

index 65d7ae0f..d6eae68f 100644

--- a/tests/common/osutil/test_default.py

+++ b/tests/common/osutil/test_default.py

@@ -49,20 +49,15 @@ class TestOSUtil(AgentTestCase):

         # setup

         retries = 3

         ifname = 'dummy'

-        with patch.object(shellutil, "run_command") as run_patch:

-            run_patch.side_effect = shellutil.CommandError("ifupdown dummy", 1, "", "")

+        with patch.object(shellutil, "run") as run_patch:

+            run_patch.return_value = 1

             # execute

             osutil.DefaultOSUtil.restart_if(osutil.DefaultOSUtil(), ifname=ifname, retries=retries, wait=0)

             # assert

             self.assertEqual(run_patch.call_count, retries)

-            cmd_queue = list(args[0] for (args, _) in run_patch.call_args_list)            

-            while cmd_queue:

-                self.assertEqual(cmd_queue.pop(0), ["ifdown", ifname])

-                # We don't expect the following command to be called because 'dummy' does

-                # not exist.

-                self.assertNotEqual(cmd_queue[0] if cmd_queue else None, ["ifup", ifname])

+            self.assertEqual(run_patch.call_args_list[0][0][0], 'ifdown {0} && ifup {0}'.format(ifname))

     def test_get_dvd_device_success(self):

         with patch.object(os, 'listdir', return_value=['cpu', 'cdrom0']):

-- 

2.31.1