cloud-init-dev team mailing list archive

[Scott Moser <ssmoser2+ubuntu@xxxxxxxxx>]

Scott Moser has proposed merging ~smoser/cloud-init:fix/1792415-fix-ovh-dhcp-routes into cloud-init:master.

Commit message:
EphemeralIPv4Network: Be more explicit when adding default route.

On OpenStack based OVH public cloud, we got DHCP response with
  fixed-address 54.36.113.86;
  option subnet-mask 255.255.255.255;
  option routers 54.36.112.1;

The router clearly is not on the subnet.  So 'ip' would fail when
we tried to add the default route.
The solution here is to add an explicit route on that interface
to the router and then add the default route.

LP: #1792415

Requested reviews:
  cloud-init commiters (cloud-init-dev)
Related bugs:
  Bug #1792415 in cloud-init: "WARNINGs and failures in log on OVH public cloud"
  https://bugs.launchpad.net/cloud-init/+bug/1792415

For more details, see:
https://code.launchpad.net/~smoser/cloud-init/+git/cloud-init/+merge/354881

see commit message
-- 
Your team cloud-init commiters is requested to review the proposed merge of ~smoser/cloud-init:fix/1792415-fix-ovh-dhcp-routes into cloud-init:master.

diff --git a/cloudinit/net/__init__.py b/cloudinit/net/__init__.py
index 3ffde52..5e87bca 100644
--- a/cloudinit/net/__init__.py
+++ b/cloudinit/net/__init__.py
@@ -698,6 +698,13 @@ class EphemeralIPv4Network(object):
                 self.interface, out.strip())
             return
         util.subp(
+            ['ip', '-4', 'route', 'add', self.router, 'dev', self.interface,
+             'src', self.ip], capture=True)
+        self.cleanup_cmds.insert(
+            0,
+            ['ip', '-4', 'route', 'del', self.router, 'dev', self.interface,
+             'src', self.ip])
+        util.subp(
             ['ip', '-4', 'route', 'add', 'default', 'via', self.router,
              'dev', self.interface], capture=True)
         self.cleanup_cmds.insert(
diff --git a/cloudinit/net/tests/test_init.py b/cloudinit/net/tests/test_init.py
index 8b444f1..58e0a59 100644
--- a/cloudinit/net/tests/test_init.py
+++ b/cloudinit/net/tests/test_init.py
@@ -515,12 +515,17 @@ class TestEphemeralIPV4Network(CiTestCase):
                 capture=True),
             mock.call(
                 ['ip', 'route', 'show', '0.0.0.0/0'], capture=True),
+            mock.call(['ip', '-4', 'route', 'add', '192.168.2.1',
+                       'dev', 'eth0', 'src', '192.168.2.2'], capture=True),
             mock.call(
                 ['ip', '-4', 'route', 'add', 'default', 'via',
                  '192.168.2.1', 'dev', 'eth0'], capture=True)]
-        expected_teardown_calls = [mock.call(
-            ['ip', '-4', 'route', 'del', 'default', 'dev', 'eth0'],
-            capture=True)]
+        expected_teardown_calls = [
+            mock.call(['ip', '-4', 'route', 'del', 'default', 'dev', 'eth0'],
+                      capture=True),
+            mock.call(['ip', '-4', 'route', 'del', '192.168.2.1',
+                       'dev', 'eth0', 'src', '192.168.2.2'], capture=True),
+        ]
 
         with net.EphemeralIPv4Network(**params):
             self.assertEqual(expected_setup_calls, m_subp.call_args_list)