openstack/training-guides
Code Issues Proposed changes

labs: set lower MTU for bridge to instance VM

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The MTU on the bridge to the instance VMs needs to be lower than 1500 to
compensate for the GRE overhead. With an MTU of 1500, one thing that
fails is ssh authentication (into the instance VM).

This patch does not help for the CirrOS 0.3.2 image which we currently
use, because it is not able to pick up MTU values via DHCP.

Change-Id: I2a04b62beef6120e811f00472aa7395ab3d683dc
Co-Authored-By: Pranav Salunke <dguitarbite@gmail.com>
This commit is contained in:
Roger Luethi 2014-09-21 19:46:25 +02:00
parent 45cb9c0381
commit 4a79c2a6a1
1 changed files with 8 additions and 0 deletions
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8
labs/scripts/setup_neutron_network.sh
View File

@ -131,6 +131,14 @@ iniset_sudo $conf DEFAULT interface_driver neutron.agent.linux.interface.OVSInte
iniset_sudo $conf DEFAULT dhcp_driver neutron.agent.linux.dhcp.Dnsmasq
iniset_sudo $conf DEFAULT use_namespaces True
iniset_sudo $conf DEFAULT verbose True
iniset_sudo $conf DEFAULT dnsmasq_config_file /etc/neutron/dnsmasq-neutron.conf
cat << DNSMASQ | sudo tee /etc/neutron/dnsmasq-neutron.conf
# Set interface MTU to 1454 (for instance, ssh authentication may fail
# otherwise due to GRE overhead)
dhcp-option-force=26,1454
DNSMASQ
killall dnsmasq
echo "Restarting the network service."
sudo service neutron-plugin-openvswitch-agent restart