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Example apps

HAProxy

This guide 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 unikraft CLI. You need a BuildKit builder. The easiest way to get one is via Docker. Alternatively, you can also directly set up and use BuildKit, see the quick start.

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

   Code
   git clone https://github.com/unikraft-cloud/examples
   cd examples/haproxy/

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

Code
unikraft login

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

Code
unikraft build . --output <my-org>/haproxy:latest
unikraft run --metro fra \
  -m 256M \
  -p 443:8404/tls+http \
  --scale-to-zero policy=on,cooldown-time=1000 \
  --image <my-org>/haproxy:latest

The output shows the instance address and other details:

Code
metro:        fra
name:         haproxy-rfx6z
uuid:         09bd081e-e082-4f73-8ba8-531123a39e2e
state:        starting
image:        <my-org>/haproxy
resources:
  memory:     256MiB
  vcpus:      1
service:
  uuid:       c349833c-dacc-7763-306e-553f512c4d0e
  name:       cool-paper-svzzr3qq
  domains:
  - fqdn:     cool-paper-svzzr3qq.fra.unikraft.app
networks:
- uuid:       494814aa-38cc-c4ed-dcad-5b7173b3033b
  private-ip: 10.0.6.5
  mac:        12:b0:a4:a5:0d:24
timestamps:
  created:    just now

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
unikraft instances list

Code
METRO  NAME           STATE    IMAGE             ARGS  MEMORY  VCPUS  FQDN                                  CREATED
fra    haproxy-rfx6z  running  <my-org>/haproxy        256MiB  1      cool-paper-svzzr3qq.fra.unikraft.app  2 minutes ago

When done, you can remove the instance:

Code
unikraft instances delete 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
unikraft --help

Or visit the CLI Reference.