Important

This method is obsolete. Keepalived is now fully supported.

Beta version for Ubuntu 16.04.

This script allows for keepalived to attach an OpenStack floating IP to an instance during a state transition. This way, a floating IP can be made high-available between instances.

Requirements

Software required:

• Python 2.7
• Python requests
• dmidecode

On Ubuntu this can be installed with the following command:

apt-get install python python-requests dmidecode

You need at least two instances on our OpenStack with a floating IP. An internal VIP is not required.

The configuration file required the tenant id, the username and the password. And of course the floating IP's.

Setup instructions

This guide assumes two servers setup in the same network (different availability zones are recommended) already setup. All instructions must be executed on both servers.

Reserve a floating IP you want to use for high-availability. Read our Getting Started guide for more instructions on floating IP's and network setup.

Script

Create the folder:

mkdir -p /etc/cloudvps/

Place the script inside folder:

wget -O /etc/cloudvps/ha-ip-failover.py https://raw.githubusercontent.com/CloudVPS/openstack-ha-floating-ip-failover/master/ha-ip-failover.py

Make it executable:

chmod +x /etc/cloudvps/ha-ip-failover.py

Place the config file:

wget -O /etc/cloudvps/ha-ip-config.json https://raw.githubusercontent.com/CloudVPS/openstack-ha-floating-ip-failover/master/ha-ip-config.json.example

Change the configuration and fill in your own values:

{
  "username": "AzureDiamond",
  "password": "hunter2",
  "tenant_id": "1234abcd...",
  "floatingips": {
  	"vrrp_group_1": {
	    "83.96.236.198": "192.168.0.7",
	    "83.96.236.143": "192.168.0.7"
	},
	"vrrp_group_2": {
    	"83.96.236.84": "192.168.0.6"
    }
  }
}

The floatingips section defines the floating IP as the key, and the internal IP as the value. The internal IP must be an IP that is attached to the instance. If instance 1 has IP 192.168.0.7 and instance 2 has IP 192.168.0.8, you will end up with two different configuration files where the internal IP's are different.

The VRRP group / instance names must be the same as in the keepalived config. Each group / instance can have multiple IP's. Do not use the same floating IP in multiple groups.

Multiple floating IP's are accepted, both on the same interface as on different interfaces.

Verify

After you've configured the script and installed the required software, you must test it to make sure it works. There is a special VERIFY option:

/etc/cloudvps/ha-ip-failover.py VERIFY

Output:

OK: Instance UUID found: 159dc1fe-6951-473d-b656-d8887fdf83f8
OK: Token creation successfull.
OK: Network API URL found.
OK: Port data found.
OK: Port data for this instance found.
OK: Floating IP's found.
OK: Floating IP 83.96.236.251, VRRP group vi_2 found in this tenant
OK: Floating IP 83.96.236.250, VRRP group vi_1 found in this tenant
OK: All configured floating IP's for VRRP group vi_2 found in this tenant
OK: All configured floating IP's for VRRP group vi_1 found in this tenant
OK: 192.168.0.5 found on instance port f05cded1-8b57-4bda-b6cb-81c1d1908520
OK: 192.168.0.5 found on instance port f05cded1-8b57-4bda-b6cb-81c1d1908520

If there are errors, they are reported:

[cloudvps] 2017-10-02 16:08:16,497 [ERROR]  Internal IP 192.168.0.5 not bound to this instance ports.

If your authentication data is not correct:

[cloudvps] 2017-10-02 16:08:59,011 [ERROR]  Request output: 404 POST https://identity.openstack.cloudvps.com/v3/auth/tokens
[cloudvps] 2017-10-02 16:08:59,011 [ERROR]  Token creation failed: 404 Client Error: Not Found for url: https://identity.openstack.cloudvps.com/v3/auth/tokens

If the config file is not valid JSON:

[cloudvps] 2017-10-02 16:10:04,951 [ERROR]  Reading config file failed: Expecting , delimiter: line 7 column 17 (char 215)

Keepalived

Keepalived is the software that handles the high availability using the VRRP protocol. Normally you can use it for high availability IP's between nodes in the same network. In our case it is used to attach a floating IP to an instance during a state transition. The virtual_ipaddress section therefore is not required.

Install Keepalived:

apt-get install keepalived

Place the config file on both servers. Make sure prority is different, and fill in a password.

vim /etc/keepalived/keepalived.conf

Server 1:

vrrp_instance vrrp_group_1 {
    state MASTER
    interface eth1
    virtual_router_id 51
    priority 150
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass
    }
    notify /etc/cloudvps/ha-ip-failover.py
}

Server 2:

vrrp_instance vrrp_group_1 {
    state MASTER
    interface eth1
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass
    }
    notify /etc/cloudvps/ha-ip-failover.py
}

This configuration has the IP on Server 1 and will only failover to server 2 when server 1 is offline.

Do note that this keepalived config uses an internal network (eth1) for the VRRP traffic.