drup / mirage-skeleton

Build skeleton and examples of simple Mirage apps

mirage-skeleton

This repository is a collection of tutorial code referred to from the Mirage website, example code for using specific devices like filesystems and networks, and higher-level applications like DHCP, DNS, and Web servers.

• tutorial/ contains the tutorial content.
• device-usage/ contains examples showing specific devices.
• applications/ contains the higher-level examples, which may use several different devices.

Prerequisites

• Install latest OPAM (at least 1.2.2), following instructions at https://opam.ocaml.org/

• Install the mirage package with OPAM, updating your package first if necessary:

    $ opam update -u
    $ opam install mirage
    $ eval `opam config env`

• Please ensure that your Mirage command-line version is at least 3.0.0 before proceeding:

    $ mirage --version
    3.0.5

Trivial example

You can check that your build environment is working and get a feel for the normal workflow by trying to compile the noop application.

    $ cd tutorials/noop
    $ mirage configure -t unix # initial setup for UNIX backend
    $ make depend # install dependencies
    $ make # build the program
    $ ./noop # run the program

Note that in the general case, you may need to specify more options at the mirage configure stage. You can find out about them with mirage configure --help. For example, you may need to specify what networking method should be used, with, e.g., --net socket or --net direct at the mirage configure stage.

Configure, Build, Run

Each unikernel lives in its own directory, and can be configured, built, and run from that location. For example:

    $ cd applications/static_website_tls
    $ mirage configure -t unix # initial setup for UNIX backend
    $ make depend # install dependencies
    $ make # build the program
    $ ./https # run the program

If you want to clean up mirage's artifacts after building, mirage clean will do the trick:

    $ cd applications/static_website_tls
    $ mirage clean

There is also a top-level Makefile at the root of this repository with convenience functions for configuring, building, and running all of the examples in one step.

    $ make all                   ## equivalent to ...
    $ make configure build
    $ make clean

Details

The Makefile simply invokes sample-specific sample/Makefile. Each of those invokes the mirage command-line tool to configure, build and run the sample, passing flags and environment as directed. The mirage command-line tool assumes that the OPAM package manager is present and is used to manage installation of an OCaml dependencies.

The mirage command-line tool supports four commands, each of which either uses config.ml in the current directory or supports passing a config.ml directly.

To configure a unikernel before building:

    $ mirage configure -t [ukvm|kvm|qubes|macosx|unix|xen]

The boot target is selected via the -t flag. The default target is unix. Depending on what devices are present in config.ml, there may be additional configuration options for the unikernel. To list the options,

    $ mirage help configure

and see the section labeled UNIKERNEL PARAMETERS.

To install dependencies

After running mirage configure:

    $ make depend

to install the list of dependencies discovered in the mirage configure phase.

To build a unikernel:

    $ make

The output will be created next to the config.ml file used.

To run a unikernel:

The mechanics of running the generated artifact will be dependent on the backend used. For details, see solo5's readme for Ukvm and Virtio, the qubes-test-mirage repository's readme for Qubes, or the MirageOS website instructions on booting Xen unikernels.

For the Macosx and Unix backends, running as a normal process should suffice.

For summaries by backend that assume the hello example, see below:

Unix:

    $ cd hello
    $ mirage configure -t unix
    $ make depend
    $ make
    $ ./hello

Xen:

    $ cd hello
    $ mirage configure -t xen
    $ make depend
    $ make
    $ sudo xl create xen.xl -c

Ukvm:

    $ cd hello
    $ mirage configure -t ukvm
    $ make depend
    $ make
    $ ./ukvm-bin hello.ukvm

Virtio:

    $ cd hello
    $ mirage configure -t virtio
    $ make depend
    $ make
    $ solo5-run-virtio ./https.virtio

Macosx:

    $ cd hello
    $ mirage configure -t macosx
    $ make depend
    $ make
    $ ./hello

Qubes:

Some specific setup in the QubesOS manager is necessary to be able to easily run MirageOS unikernels -- please see the qubes-test-mirage readme for details.

    $ cd hello
    $ mirage configure -t qubes
    $ make depend
    $ make
    $ ~/test-unikernel hello.xen unikernel-test-vm

To clean up after building a unikernel:

    $ make clean