Neutron/LBaaS/HowToRun
Getting the Code
Currently, both the quantum, python-quantumclient, and devstack code is under review. Please pull from the following reviews to get the latest code:
- quantum: https://review.openstack.org/#/c/22794/
- python-quantumclient: https://review.openstack.org/#/c/22922/
- devstack: https://review.openstack.org/#/c/22937/
System Setup
sudo apt-get install haproxy
add the following lines to your localrc:
enable_service q-lbaas Q_SERVICE_PLUGINS=quantum.plugins.services.loadbalancer.plugin.LoadBalancerPlugin
then re-run stack.sh
Topology Setup
Spin up three VMs, two to be servers, and one to be a client.
nova boot --image <image-uuid> --flavor 1 server1 nova boot --image <image-uuid> --flavor 1 server2 nova boot --image <image-uuid> --flavor 1 client
Get the UUID of the private subnet.
quantum subnet-list
Create a Pool:
quantum lb-pool-create --lb-method ROUND_ROBIN --name mypool --protocol HTTP --subnet-id <subnet-id>
Create Members (using the IPs of server1 and server2):
nova list quantum lb-member-create --address <server1-ip> --protocol-port 80 mypool quantum lb-member-create --address <server2-ip> --protocol-port 80 mypool
Create a Healthmonitor and associated it with the pool:
quantum lb-healthmonitor-create --delay 3 --type HTTP --max-retries 3 --timeout 3 quantum lb-healthmonitor-associate <healthmonitor-uuid> mypool
Create a VIP
quantum lb-vip-create --name myvip --protocol-port 80 --protocol HTTP --subnet-id <subnet-id> mypool
note the address for use below.
Validation
We now have two hosts with a load balancer pointed at them, but those hosts are serving up any HTTP content.
A simple trick is to use netcat on the hosts to implement a simple webserver. For example, run:
while true; do echo -e 'HTTP/1.0 200 OK\r\n\r\n<servername>' | sudo nc -l -p 80 ; done
replacing <servername> with "server1" and "server2" as appropriate. (If you have python installed, you can also create an index.html with the text "server1" or "server2" then in the same directory run: python -m SimpleHTTPServer)
From your client, use wget to make sure you can access server1 and server2 as expected.
wget -O - http://<server1-ip> wget -O - http://<server2-ip>
Then use wget to hit the VIP IP several times in succession. You should bounce between seeing server1 and server2.
wget -O - http://<vip-ip> wget -O - http://<vip-ip> wget -O - http://<vip-ip> wget -O - http://<vip-ip>
Full list of LBaaS CLI commands is available at Quantum/LBaaS/CLI
Troubleshooting
LBaas is implemented similar to L3 + DHCP using namespaces. You can use "ip netns list" to find the namespace named qlbaas-<pool_id>, and then test connectivity from that namespace.
Use "screen -x stack" to view the q-svc and q-lbaas tabs for errors.
Grep syslog for "haproxy" to see messages from Haproxy (though they are quite cryptic!)
