Guides

HAProxy

This guides shows you how to use HAProxy. HAProxy is a free and open source software that provides a high availability load balancer and reverse proxy for TCP and HTTP-based apps that spreads requests across many servers.

To run this example, follow these steps:

1. Install the kraft CLI tool and a container runtime engine, for example Docker.

2. Clone the examples repository and cd into the examples/haproxy/ directory:

Code(bash)
 
git clone https://github.com/kraftcloud/examples
cd examples/haproxy/

Make sure to log into Unikraft Cloud by setting your token and a metro close to you. This guide uses fra (Frankfurt, 🇩🇪):

Code(bash)
 
# Set Unikraft Cloud access token
export UKC_TOKEN=token
# Set metro to Frankfurt, DE
export UKC_METRO=fra

When done, invoke the following command to deploy this app on Unikraft Cloud:

Code(bash)
 
kraft cloud deploy -p 443:8404 -M 256 .

The output shows the instance address and other details:

Code(ansi)
 
[●] Deployed successfully!
 │
 ├────────── name: haproxy-rfx6z
 ├────────── uuid: 09bd081e-e082-4f73-8ba8-531123a39e2e
 ├───────── state: running
 ├─────────── url: https://cool-paper-svzzr3qq.fra.unikraft.app
 ├───────── image: haproxy@sha256:32296847231c151506820ec4914c1d7416e5b7200caf07c1e40eaa3ea5033d21
 ├───── boot time: 26.60 ms
 ├──────── memory: 256 MiB
 ├─────── service: cool-paper-svzzr3qq
 ├── private fqdn: haproxy-rfx6z.internal
 ├──── private ip: 172.16.6.5
 └────────── args: /usr/bin/haproxy -f /etc/haproxy/haproxy.conf

In this case, the instance name is haproxy-rfx6z and the address is https://cool-paper-svzzr3qq.fra.unikraft.app. They're different for each run.

To test, point your browser at the /stats endpoint (for example, https://cool-paper-svzzr3qq.fra.unikraft.app/stats).

You can list information about the instance by running:

Code(bash)
 
kraft cloud instance list

Code(text)
 
NAME           FQDN                                  STATE    CREATED AT    IMAGE                               MEMORY   ARGS                               BOOT TIME
haproxy-rfx6z  cool-paper-svzzr3qq.fra.unikraft.app  running  1 minute ago  haproxy@sha256:32296847231c1515...  256 MiB  /usr/bin/haproxy -f /etc/hapro...  26596us

When done, you can remove the instance:

Code(bash)
 
kraft cloud instance remove haproxy-rfx6z

Customize your app

To customize the app, update the files in the repository, listed below:

• Kraftfile: the Unikraft Cloud specification, including command-line arguments
• Dockerfile: In case you need to add files to your instance's rootfs

Learn more

Use the --help option for detailed information on using Unikraft Cloud:

Code(bash)
 
kraft cloud --help

Or visit the CLI Reference.