Deploying a Public Cloud Load Balancer

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KB0050293

Deploying a Public Cloud Load Balancer


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Objective

This tutorial explains the following Load Balancer configurations:

  • Deploying a basic HTTP Load Balancer Private → Private
  • Deploying a basic HTTP Load Balancer Public → Private

Requirements

Instructions

Load Balancer within your Private Network (Private → Private)

When you create a Load Balancer, by default it gets a private IP in the private network selected during its creation.

We want to balance the load between the two backends: backend--1 and backend--2.

(os_client) ~ openstack server list     

+--------------------------------------+------------+--------+-----------------------------------------------------------------------+--------------+--------+
| ID                                   | Name       | Status | Networks                                                              | Image        | Flavor |
+--------------------------------------+------------+--------+-----------------------------------------------------------------------+--------------+--------+
| 5b8c722b-57d0-460a-b2c0-b0a681bf4e52 | backend--2 | ACTIVE | priv-net=10.0.111.243                                                 | Ubuntu 20.04 | d2-4   |
| 9a43ce4c-e0fe-4a54-81f5-aad3ac6f8e88 | backend--1 | ACTIVE | priv-net=10.0.112.172                                                 | Ubuntu 20.04 | d2-4   |
| 67b9372e-bf08-4c57-9945-42b07dbfcd36 | bastion    | ACTIVE | Ext-Net=2001:48f0:163:100::1662, 169.254.10.150; priv-net=10.0.109.243 | Ubuntu 20.04 | d2-8   |
+--------------------------------------+------------+--------+-----------------------------------------------------------------------+--------------+--------+

Step 1: Create the Load Balancer

openstack loadbalancer create --name loadbalancer_private_to_private --vip-subnet-id <private_subnet_id>
+---------------------+--------------------------------------+
| Field               | Value                                |
+---------------------+--------------------------------------+
| admin_state_up      | True                                 |
| availability_zone   | None                                 |
| created_at          | 2022-06-29T12:24:35                  |
| description         |                                      |
| flavor_id           | 2d4bc92c-38fc-4b50-9484-8351ab0c4e69 |
| id                  | 4db76fce-f8f7-435f-8031-716f82a7f1dc |
| listeners           |                                      |
| name                | loadbalancer_private_to_private      |
| operating_status    | OFFLINE                              |
| pools               |                                      |
| project_id          | 96575fa614c14aa7b001c7e121d772f2     |
| provider            | amphora                              |
| provisioning_status | PENDING_CREATE                       |
| updated_at          | None                                 |
| vip_address         | 10.0.3.50                            |
| vip_network_id      | d20943ed-5159-4805-b48a-2375dd93e480 |
| vip_port_id         | 631f240c-16f7-483f-b1c4-6eff7a8adcf4 |
| vip_qos_policy_id   | None                                 |
| vip_subnet_id       | 4ecfca39-6e87-496a-8692-2e7f43bf7767 |
| tags                |                                      |
+---------------------+--------------------------------------+

Load Balancer Flavors

If you do not provide the parameter --flavor during the creation, the Load Balancer will be of a small size.

Use the following command to display the flavors in OpenStack:

openstack loadbalancer flavor list
+--------------------------------------+--------+--------------------------------------+---------+
| id                                   | name   | flavor_profile_id                    | enabled |
+--------------------------------------+--------+--------------------------------------+---------+
| 2d4bc92c-38fc-4b50-9484-8351ab0c4e69 | small  | e9970d43-695e-4947-8005-38be80bc966a | True    |
| 4d6a92af-d4c8-4e81-8596-e3b14159e232 | medium | 24559467-a4dd-4712-9981-93276400fa17 | True    |
| fd43698c-0a2f-4124-9695-478f9114a07c | large  | 3ded4565-7bc7-40b3-9a2c-83077035b134 | True    |
+--------------------------------------+--------+--------------------------------------+---------+

Status

The Load Balancer creation will take some time, mainly to create the instance and to configure the network.

For the next configuration, you will have to wait until the provisioning_status becomes ACTIVE.

You can already see when creating our Load Balancer that it is associated with a Virtual IP address (VIP).

| vip_address | 10.0.3.50 |

This will be our Load Balancer IP inside our Private Network.

Step 2: Create a listener

openstack loadbalancer listener create --protocol-port 80 --protocol HTTP --name listener <loadbalancer_id>
+-----------------------------+--------------------------------------+
| Field                       | Value                                |
+-----------------------------+--------------------------------------+
| admin_state_up              | True                                 |
| connection_limit            | -1                                   |
| created_at                  | 2022-06-29T12:34:37                  |
| default_pool_id             | None                                 |
| default_tls_container_ref   | None                                 |
| description                 |                                      |
| id                          | e2e67b80-61e6-43bd-b1f1-703ab1abc7af |
| insert_headers              | None                                 |
| l7policies                  |                                      |
| loadbalancers               | 4db76fce-f8f7-435f-8031-716f82a7f1dc |
| name                        | listener                             |
| operating_status            | OFFLINE                              |
| project_id                  | 96575fa614c14aa7b001c7e121d772f2     |
| protocol                    | HTTP                                 |
| protocol_port               | 80                                   |
| provisioning_status         | PENDING_CREATE                       |
| sni_container_refs          | []                                   |
| timeout_client_data         | 50000                                |
| timeout_member_connect      | 5000                                 |
| timeout_member_data         | 50000                                |
| timeout_tcp_inspect         | 0                                    |
| updated_at                  | None                                 |
| client_ca_tls_container_ref | None                                 |
| client_authentication       | NONE                                 |
| client_crl_container_ref    | None                                 |
| allowed_cidrs               | None                                 |
| tls_ciphers                 | None                                 |
| tls_versions                | None                                 |
| alpn_protocols              | None                                 |
| tags                        |                                      |
+-----------------------------+--------------------------------------+

Step 3: Create the pool

openstack loadbalancer pool create --name pool --lb-algorithm ROUND_ROBIN --listener <listener_id> --protocol HTTP
+----------------------+--------------------------------------+
| Field                | Value                                |
+----------------------+--------------------------------------+
| admin_state_up       | True                                 |
| created_at           | 2022-06-29T12:41:52                  |
| description          |                                      |
| healthmonitor_id     |                                      |
| id                   | f0c833f7-53bb-46b7-8818-637d89a68089 |
| lb_algorithm         | ROUND_ROBIN                          |
| listeners            | e2e67b80-61e6-43bd-b1f1-703ab1abc7af |
| loadbalancers        | 4db76fce-f8f7-435f-8031-716f82a7f1dc |
| members              |                                      |
| name                 | pool                                 |
| operating_status     | OFFLINE                              |
| project_id           | 96575fa614c14aa7b001c7e121d772f2     |
| protocol             | HTTP                                 |
| provisioning_status  | PENDING_CREATE                       |
| session_persistence  | None                                 |
| updated_at           | None                                 |
| tls_container_ref    | None                                 |
| ca_tls_container_ref | None                                 |
| crl_container_ref    | None                                 |
| tls_enabled          | False                                |
| tls_ciphers          | None                                 |
| tls_versions         | None                                 |
| tags                 |                                      |
| alpn_protocols       | None                                 |
+----------------------+--------------------------------------+

Step 4. Add the servers

openstack loadbalancer member create --subnet-id <private_subnet_id> --address <server_ip_address>  --protocol-port 80 <pool_id>
+---------------------+--------------------------------------+
| Field               | Value                                |
+---------------------+--------------------------------------+
| address             | 10.0.3.123                           |
| admin_state_up      | True                                 |
| created_at          | 2022-06-29T12:48:55                  |
| id                  | fbe34622-2538-4896-bda3-d92ca66f7a30 |
| name                |                                      |
| operating_status    | NO_MONITOR                           |
| project_id          | 96575fa614c14aa7b001c7e121d772f2     |
| protocol_port       | 80                                   |
| provisioning_status | PENDING_CREATE                       |
| subnet_id           | 4ecfca39-6e87-496a-8692-2e7f43bf7767 |
| updated_at          | None                                 |
| weight              | 1                                    |
| monitor_port        | None                                 |
| monitor_address     | None                                 |
| backup              | False                                |
| tags                |                                      |
+---------------------+--------------------------------------+

Step 5. Use your Load Balancer

root@bastion:~# curl http://10.0.3.50/backend.txt
Backend 1
root@bastion:~# curl http://10.0.3.50/backend.txt
Backend 2

Load Balancer with a public IP (Public → Private)

We will be using the Load Balancer previously deployed in a private network and use an OpenStack Floating IP.

We will need to create a Floating IP address on the public network (Ext-Net), and then associate it to the Load Balancer's VIP port.

In order to use a Floating IP, we will need to create an L3 router and configure an external Gateway on it.

What is the role of a Floating IP?

Floating IP addresses are used in the OpenStack universe to expose resources (Neutron port) to the Internet. You can associate a Floating IP to a private network port only.

You can expose two types of resources:

  • An instance with a private port
  • An Load Balancer Virtual IP address (VIP)

Floating IP currently does not support IPv6.

You can read more about it on our dedicated Concepts page.

Step 1: Create the router

openstack router create <router_name>

Step 2: Add an external Gateway on your router

openstack router set --external-gateway Ext-Net <router_name>

Step 3: Attach the router to your Private Network

openstack router add subnet <router_id> <subnet_id>

Step 4: Now we can create a Floating IP on the public network: Ext-Net

openstack floating ip create Ext-Net
+---------------------+--------------------------------------+
| Field               | Value                                |
+---------------------+--------------------------------------+
| created_at          | 2022-06-29T13:19:10Z                 |
| description         |                                      |
| dns_domain          | None                                 |
| dns_name            | None                                 |
| fixed_ip_address    | None                                 |
| floating_ip_address | 169.254.10.250                       |
| floating_network_id | b2c02fdc-ffdf-40f6-9722-533bd7058c06 |
| id                  | 5f1ad04e-f341-457b-a174-a1204ee4feef |
| name                | 169.254.10.250                       |
| port_details        | None                                 |
| port_id             | None                                 |
| project_id          | 96575fa614c14aa7b001c7e121d772f2     |
| qos_policy_id       | None                                 |
| revision_number     | 0                                    |
| router_id           | None                                 |
| status              | DOWN                                 |
| subnet_id           | None                                 |
| tags                | []                                   |
| updated_at          | 2022-06-29T13:19:10Z                 |
+---------------------+--------------------------------------+

Step 5: Associate its ID to the Load Balancer's VIP address

openstack floating ip set --port <load_balancer_vip_port_id> <floating_ip_id>

Step 6: Using your Load Balancer with its public IP

❯ curl http://169.254.10.250/backend.txt
Backend 2
❯ curl http://169.254.10.250/backend.txt
Backend 1
❯ curl http://169.254.10.250/backend.txt
Backend 2
❯ curl http://169.254.10.250/backend.txt
Backend 1
❯ curl http://169.254.10.250/backend.txt
Backend 2

Where to place the public Gateway

The public Gateway is defined by an L3 router attached to a private network with an external Gateway.

diagram

Delete the Load Balancer

openstack loadbalancer delete [--cascade] [--wait] <load_balancer>

Go further

Getting started with Load Balancer on Public Cloud

Official documentation of OpenStack Octavia

Cookbook OpenStack Octavia

OpenStack Floating IP

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