Decrease MTU to account for IPv6 header
(MTU - 50) only supports VxLAN over IPv4, decrease it
to support IPv6 as well, which is 20 bytes larger.
Change-Id: I0cf258770f628c1b4fb590bd274b5433fbcc1450
diff --git a/playbooks/pre.yaml b/playbooks/pre.yaml
index ff97a1f..68cb1d8 100644
--- a/playbooks/pre.yaml
+++ b/playbooks/pre.yaml
@@ -19,12 +19,13 @@
{% endfor -%}
{{- mtus|min -}}
- name: Calculate external_bridge_mtu
- # 50 bytes is overhead for vxlan (which is greater than GRE
+ # 30 bytes is overhead for vxlan (which is greater than GRE
# allowing us to use either overlay option with this MTU.
+ # 40 bytes is overhead for IPv6, which will also support an IPv4 overlay.
# TODO(andreaf) This should work, but it may have to be reconcilied with
# the MTU setting used by the multinode setup roles in multinode pre.yaml
set_fact:
- external_bridge_mtu: "{{ local_mtu | int - 50 }}"
+ external_bridge_mtu: "{{ local_mtu | int - 30 - 40 }}"
roles:
- configure-swap
- setup-stack-user