From 70e908344dd4db81652264a2de2c04ce9666bb46 Mon Sep 17 00:00:00 2001
From: Tom Barron <tpb@dyncloud.net>
Date: Tue, 16 Jul 2019 14:55:21 -0400
Subject: [PATCH] Conditionally restore default route in setup_ipv6

Restoring the default IPv6 route is not needed in CI and
fails when there are multiple defaults, but it is useful
in local devstacks where multiple default routes are not
typical.

Add a variable in settings and use it to make this behavior
conditional and set it to False for the lvm job.

Closes-bug: #1836788
Change-Id: Id73de8100509ec5935641f5f35f93f482d108bcd
---
 contrib/ci/pre_test_hook.sh |  1 +
 devstack/plugin.sh          | 22 +++++++++++++++-------
 devstack/settings           |  1 +
 3 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/contrib/ci/pre_test_hook.sh b/contrib/ci/pre_test_hook.sh
index ec00e1fdfe..224a29a30b 100755
--- a/contrib/ci/pre_test_hook.sh
+++ b/contrib/ci/pre_test_hook.sh
@@ -194,6 +194,7 @@ if [[ "$MANILA_SETUP_IPV6" == True ]]; then
     # regular Neutron DevStack configuration.
     echo "NEUTRON_CREATE_INITIAL_NETWORKS=False" >> $localconf
     echo "IP_VERSION=4+6" >> $localconf
+    echo "MANILA_RESTORE_IPV6_DEFAULT_ROUTE=False" >> $localconf
 fi
 
 if [[ "$DRIVER" == "generic"* ]]; then
diff --git a/devstack/plugin.sh b/devstack/plugin.sh
index 6ef6451128..73d069e7c1 100755
--- a/devstack/plugin.sh
+++ b/devstack/plugin.sh
@@ -1013,8 +1013,12 @@ function install_libraries {
 
 function setup_ipv6 {
 
-    # save IPv6 default route to add back later after enabling forwarding
-    local default_route=$(ip -6 route | grep default | cut -d ' ' -f1,2,3,4,5)
+    # This will fail with multiple default routes and is not needed in CI
+    # but may be useful when developing with devstack locally
+    if [ $(trueorfalse False MANILA_RESTORE_IPV6_DEFAULT_ROUTE) == True ]; then
+        # save IPv6 default route to add back later after enabling forwarding
+        local default_route=$(ip -6 route | grep default | cut -d ' ' -f1,2,3,4,5)
+    fi
 
     # make sure those system values are set
     sudo sysctl -w net.ipv6.conf.lo.disable_ipv6=0
@@ -1130,11 +1134,15 @@ function setup_ipv6 {
     # log the systemd status
     sudo systemctl status $QUAGGA_SERVICES
 
-    # add default IPv6 route back
-    if ! [[ -z $default_route ]]; then
-        # "replace" should ignore "RTNETLINK answers: File exists"
-        # error if the route wasn't flushed by the bgp setup we did earlier.
-        sudo ip -6 route replace $default_route
+    # This will fail with mutltiple default routes and is not needed in CI
+    # but may be useful when developing with devstack locally
+    if [ $(trueorfalse False MANILA_RESTORE_IPV6_DEFAULT_ROUTE) == True ]; then
+        # add default IPv6 route back
+        if ! [[ -z $default_route ]]; then
+            # "replace" should ignore "RTNETLINK answers: File exists"
+            # error if the route wasn't flushed by the bgp setup we did earlier.
+            sudo ip -6 route replace $default_route
+        fi
     fi
 
 }
diff --git a/devstack/settings b/devstack/settings
index 827da80f40..5d4cb5b017 100644
--- a/devstack/settings
+++ b/devstack/settings
@@ -210,6 +210,7 @@ MANILA_DATA_COPY_CHECK_HASH=${MANILA_DATA_COPY_CHECK_HASH:=True}
 
 # Manila IPv6 Setup flag
 MANILA_SETUP_IPV6=${MANILA_SETUP_IPV6:=False}
+MANILA_RESTORE_IPV6_DEFAULT_ROUTE=${MANILA_RESTORE_IPV6_DEFAULT_ROUTE:=True}
 
 # Enable manila services
 # ----------------------