Change MTU logic to allow for lower MTUs automatically

Conflicts:
	devstack/settings
	zuul.d/ironic-jobs.yaml

Change-Id: I40d357e716b589585493824cfd963fd5f579bd81
(cherry picked from commit cf074202e5)
This commit is contained in:
Julia Kreger 2019-09-21 17:16:58 -07:00 committed by Dmitry Tantsur
parent 05bf8f69d6
commit 1a85a15761
1 changed files with 5 additions and 1 deletions

View File

@ -9,4 +9,8 @@ source $DEST/ironic/devstack/common_settings
local_mtu=$(ip link show | sed -ne 's/.*mtu \([0-9]\+\).*/\1/p' | sort -n | head -1)
# 50 bytes is overhead for vxlan (which is greater than GRE
# allowing us to use either overlay option with this MTU.
PUBLIC_BRIDGE_MTU=$((local_mtu - 50))
# However, if traffic is flowing over IPv6 tunnels, then
# The overhead is essentially another 100 bytes. In order to
# handle both cases, lets go ahead and drop the maximum by
# 100 bytes.
PUBLIC_BRIDGE_MTU=${OVERRIDE_PUBLIC_BRIDGE_MTU:-$((local_mtu - 100))}