In agent mode tsn-no-forwarding ping in fabric failed.

This happened because tsn-no-forwarding does not let IP route get added as it is
not a forwarding agent and is to be used for services like dhcp/dns. This
blocked fabric routes resulting in ping failure.

Solution:
Add exception for routes in fabric vrf.

Change-Id: Iadd386622e7f9756dabcaaf82782a00bacef3317
Closes-bug: #1724064

src/vnsw/agent/oper/agent_route.cc

@@ -824,7 +824,8 @@ bool AgentRouteData::AddChangePath(Agent *agent, AgentPath *path,
             local_route = true;
         if (rt->FindLocalPath())
             local_route = true;
-        if (is_inet_rt && (!service_address && !local_route))
+        if (is_inet_rt && (!service_address && !local_route) &&
+            (rt->vrf()->GetName().compare(agent->fabric_vrf_name()) != 0))
             path->set_inactive(true);
     }
 

src/vnsw/agent/oper/test/test_tsn_elector.cc

@@ -445,6 +445,30 @@ TEST_F(TsnElectorTest, Test_6) {
     EXPECT_FALSE(VmPortActive(input, 0));
 }
 
+//Refer: https://bugs.launchpad.net/juniperopenstack/+bug/1724064
+//Routes in fabric vrf should remain active in tsn-no-forwarding-mode
+TEST_F(TsnElectorTest, Test_7) {
+    client->Reset();
+    CreateVmportEnv(input, 1);
+    client->WaitForIdle();
+    AddIPAM("vn1", ipam_info, 1);
+    client->WaitForIdle();
+    EXPECT_TRUE(VmPortActive(input, 0));
+
+    VrfEntry *fabric_vrf = agent_->fabric_vrf();
+    InetUnicastAgentRouteTable *inet4_table = fabric_vrf->
+        GetInet4UnicastRouteTable();
+    InetUnicastRouteEntry *default_rt =
+        inet4_table->FindRoute(Ip4Address::from_string("0.0.0.0"));
+    EXPECT_FALSE(default_rt->GetActivePath()->inactive());
+
+    //Delete
+    DeleteVmportEnv(input, 1, true);
+    DelIPAM("vn1");
+    client->WaitForIdle();
+    EXPECT_FALSE(VmPortActive(input, 0));
+}
+
 int main(int argc, char **argv) {
     GETUSERARGS();
     strcpy(init_file, DEFAULT_VNSW_TSN_NO_FORWARDING_CONFIG_FILE);