Disable scatter-gather offload on host bridges

Disable scatter-gather offload on host bridges to eliminate
kernel traces that may impact container connectivity. Only
addressing AIO interfaces for now as host configuration for
actual deployments resides in documentation.

Change-Id: Ia66b2bb64b9ace66f5fa3ca8edcc9909af54a4f2
Partial-Bug: #1488815
Co-Authored-By: Evan Callicoat <apsu@propter.net>

etc/network/interfaces.d/aio_interfaces.cfg

@@ -13,6 +13,7 @@ iface br-mgmt inet static
     bridge_ports none
     address 172.29.236.100
     netmask 255.255.252.0
+    offload-sg off
 
 auto br-vxlan
 iface br-vxlan inet static
@@ -22,6 +23,7 @@ iface br-vxlan inet static
     bridge_ports none
     address 172.29.240.100
     netmask 255.255.252.0
+    offload-sg off
     # To ensure ssh checksum is correct
     up /sbin/iptables -A POSTROUTING -t mangle -p tcp --dport 22 -j CHECKSUM --checksum-fill
     down /sbin/iptables -D POSTROUTING -t mangle -p tcp --dport 22 -j CHECKSUM --checksum-fill
@@ -37,6 +39,7 @@ iface br-storage inet static
     bridge_ports none
     address 172.29.244.100
     netmask 255.255.252.0
+    offload-sg off
 
 auto br-vlan
 iface br-vlan inet static
@@ -45,6 +48,7 @@ iface br-vlan inet static
     bridge_fd 0
     address 172.29.248.100
     netmask 255.255.252.0
+    offload-sg off
     # Create veth pair, don't bomb if already exists
     pre-up ip link add br-vlan-veth type veth peer name eth12 || true
     # Set both ends UP

scripts/bootstrap-aio.sh

@@ -103,6 +103,7 @@ apt-get purge -y libmysqlclient18 mysql-common
 apt-get install -y bridge-utils \
                    build-essential \
                    curl \
+                   ethtool \
                    git-core \
                    ipython \
                    linux-image-extra-$(uname -r) \