Merge pull request #89 from sombrafam/backports-version-pinning-optio…

…n-to-20.03

[stable] Make version pinning optional

config.yaml

@@ -305,3 +305,19 @@ options:
       .
       Changing this config option will restart openvswitch-switch, resulting
       in an expected data plane outage while the service restarts.
+  enable-version-pinning:
+    type: boolean
+    default: true
+    description: |
+      OVN is a distributed system, and special consideration must be given to
+      the process used to upgrade OVN.
+
+      In order to successfully perform a rolling upgrade, the ovn-controller
+      process needs to understand the structure of the database for the version
+      you are upgrading from and to simultaneously.
+
+      Rolling upgrades are supported as long as the span of versions used in
+      the system is within the previous and the next upstream OVN LTS version.
+
+      If you are upgrading across LTS boundaries you may need to use version
+      pinning to avoid data plane outage during the upgrade.

lib/charms/ovn_charm.py

@@ -792,7 +792,8 @@ def configure_ovs(self, sb_conn, mlockall_changed):
                            'external-ids:system-id={}'
                            .format(self.get_ovs_hostname()),
                            'external-ids:ovn-remote={}'.format(sb_conn),
-                           'external_ids:ovn-match-northd-version=true',
+                           'external_ids:ovn-match-northd-version={}'
+                           .format(self.options.enable_version_pinning),
                            ):
             cmd = cmd + ('--', 'set', 'open-vswitch', '.', ovs_ext_id)
         self.run(*cmd)

unit_tests/test_lib_charms_ovn_charm.py

@@ -770,7 +770,7 @@ def test_configure_bridges(self):
 class TestOVNChassisCharm(Helper):
 
     def setUp(self):
-        super().setUp(config={
+        self.local_config = {
             'enable-hardware-offload': False,
             'enable-sriov': False,
             'enable-dpdk': False,
@@ -779,7 +779,8 @@ def setUp(self):
             'ovn-bridge-mappings': (
                 'provider:br-provider other:br-other'),
             'prefer-chassis-as-gw': True,
-        })
+            'enable-version-pinning': False}
+        super().setUp(config=self.local_config)
 
     def test_optional_openstack_metadata(self):
         self.assertEquals(self.target.packages, ['ovn-host'])
@@ -915,7 +916,7 @@ def test_configure_ovs(self):
                 '--', 'set', 'open-vswitch', '.',
                 'external-ids:ovn-remote=fake-sb-conn-str',
                 '--', 'set', 'open-vswitch', '.',
-                'external_ids:ovn-match-northd-version=true',
+                'external_ids:ovn-match-northd-version=False',
             ),
         ])
         self.service_restart.assert_not_called()
@@ -941,7 +942,7 @@ def test_configure_ovs(self):
                 '--', 'set', 'open-vswitch', '.',
                 'external-ids:ovn-remote=fake-sb-conn-str',
                 '--', 'set', 'open-vswitch', '.',
-                'external_ids:ovn-match-northd-version=true',
+                'external_ids:ovn-match-northd-version=False',
             ),
             mock.call('ovs-vsctl', '--id', '@manager',
                       'create', 'Manager', 'target="ptcp:6640:127.0.0.1"',
@@ -950,6 +951,39 @@ def test_configure_ovs(self):
         ])
         assert self.service_restart.called
 
+    def test_configure_ovs_version_pinning(self):
+        self.local_config.update({'enable-version-pinning': True})
+        self.target = ovn_charm.BaseOVNChassisCharm()
+        self.patch_target('run')
+        self.patch_object(ovn_charm.OVNConfigurationAdapter, 'ovn_key')
+        self.patch_object(ovn_charm.OVNConfigurationAdapter, 'ovn_cert')
+        self.patch_object(ovn_charm.OVNConfigurationAdapter, 'ovn_ca_cert')
+        self.patch_object(ovn_charm.ch_core.host, 'service_restart')
+        self.patch_target('get_data_ip')
+        self.get_data_ip.return_value = 'fake-data-ip'
+        self.patch_target('get_ovs_hostname')
+        self.get_ovs_hostname.return_value = 'fake-ovs-hostname'
+        self.patch_target('check_if_paused')
+        self.check_if_paused.return_value = (None, None)
+        self.target.configure_ovs('fake-sb-conn-str', False)
+        self.run.assert_has_calls([
+            mock.call('ovs-vsctl', '--no-wait', 'set-ssl',
+                      mock.ANY, mock.ANY, mock.ANY),
+            mock.call(
+                'ovs-vsctl',
+                '--', 'set', 'open-vswitch', '.',
+                'external-ids:ovn-encap-type=geneve',
+                '--', 'set', 'open-vswitch', '.',
+                'external-ids:ovn-encap-ip=fake-data-ip',
+                '--', 'set', 'open-vswitch', '.',
+                'external-ids:system-id=fake-ovs-hostname',
+                '--', 'set', 'open-vswitch', '.',
+                'external-ids:ovn-remote=fake-sb-conn-str',
+                '--', 'set', 'open-vswitch', '.',
+                'external_ids:ovn-match-northd-version=True',
+            ),
+        ])
+
     def test_render_nrpe(self):
         self.patch_object(ovn_charm.nrpe, 'NRPE')
         self.patch_object(ovn_charm.nrpe, 'add_init_service_checks')