Mirage is a programming framework for constructing secure, high-performance network applications across a variety of cloud computing and mobile platforms. Code can be developed on a normal OS such as Linux or MacOS X, and then compiled into a fully-standalone, specialised unikernel that runs under the Xen hypervisor. Since Xen powers most public cloud computing infrastructure such as Amazon EC2, this lets your servers run more cheaply, securely and finer control than with a full software stack.
The most up-to-date documentation can be found at the homepage, at http://www.openmirage.org. The site is self-hosted and a useful example, available at https://github.com/mirage/mirage-www. Simpler skeleton applications are found at https://github.com/mirage/mirage-skeleton.
This repository includes:
- a commmand-line tool to create and deploy applications with Mirage.
- in
types/
, a library of type signatures that compliant applications use.
There are several diverse backends in Mirage that require rather specialised build steps (from Javascript to Xen unikernels), and this complexity is wrapped up in the tool.
To work with Mirage, you'll need the following prerequisites installed:
- a working OCaml compiler (4.01.0 or higher).
- the OPAM source package manager (1.2.0 or higher).
- an x86_64 or armel Linux host to compile Xen kernels, or FreeBSD, OpenBSD or MacOS X for the userlevel version.
There are three stages to using mirage
:
-
a configuration phase where OPAM package dependencies are satisfied.
-
a build phase where the compiler and any support scripts are run.
-
a run phase where
mirage
spawns and tracks the progress of the deployment (e.g. as a UNIX process or a Xen kernel).
mirage
currently uses a configuration file to build a Mirage unikernel.
While we're documenting it all, please see the lib_test
directory in
this repository for the regression examples. The latest instructions are
also to be found at http://openmirage.org/docs
Provided that one and only one file of name <foo>.conf
(where
<foo>
can be any string) is present in the current working
directory, the command:
mirage configure
will configure your project. It will generate a Makefile
and
main.ml
with the appropriate boilerplate for your chosen
platform.
To configure for the unix-direct target (using tap interfaces), do:
mirage configure --unix
To build for the xen target, do:
mirage configure --xen
Once configuration is complete, you can install the OPAM packages required by this unikernel by:
make depend
The command:
mirage build
will build your project. Likewise, you can use the --unix
or --xen
switches to build for a particular target.
The command:
mirage run # [--unix or --xen]
will run the unikernel on the selected backend.
-
Under the unix-direct backend (
--unix
),mirage
sets up a virtual interface (tap) is passes its fd to the unikernel that will use it to perform networking operations. -
Under the xen backend (
--xen
),mirage
creates a xl configuration file and usesxl
to run the unikernel locally. Xen has to be installed and running on the machine.
In order to deploy a Mirage unikernel to Amazon EC2, you need to
install the AWS tools on your machine, build a unikernel with the
--xen
option and then use the ec2.sh
script (in directory
script
) in order to register you kernel with AWS. Then you can start
your kernel with the web interface to AWS or any other mean AWS
provides to start EC2 instances.