There are three stages to using Mirari:
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 Mirari spawns and tracks the progress of the deployment (e.g. as a UNIX process or a Xen kernel).
Mirari currently uses a configuration file to build a Mirage unikernel. Support for command line arguments should be available soon.
An example of an
# IP configuration # This will use DHCP for configuring the unikernel's network interfaces ip-use-dhcp: true # This will manually set an IPv4 to the unikernel's network # interfaces. For now, this technique only works when a unikernel has # only one network interface. # ip-address: 10.0.0.2 # ip-netmask: 255.255.255.0 # ip-gateway: 10.0.0.1 # Filesystem configuration. Directories can be specified here, and # they will be compiled into a "filesystem" where each file will be # presented to the unikernel via a key value interface. For example # here, there will be two databases, named respectively "static" and # "template", presenting the content of dir "../files" and "../templ" # respectively. fs-static: ../files fs-template: ../tmpl # HTTP configuration http-port: 80 http-address: * # Main function # If your main is a Dispatch function for cohttp main-http: Dispatch.main # If Ping.min has signature Net.Manager.t -> Net.Manager.interface -> Net.Manager.id -> 'a Lwt.t # main-ip: Ping.min # Noip.main must have signature unit -> 'a Lwt.t (do not use networking) # main-noip: Noip.main # Dependencies depends: cohttp.syntax, uri, re, cow.syntax packages: mirage-net, cow # Target (Select a target compiler: takes precedence over --xen or # --unix switch on the command line) compiler: 4.01.0dev+mirage-xen # XL parameters. They will be used for creating the xl config file # when doing a `mirari run --xen`. xl-memory: 32 xl-on_crash: preserve xl-vif: [ 'mac=00:16:3E:74:34:32' ]
dependsis a list of ocamlfind libraries
packagesis a list of OPAM packages (which contains the
compileris a OPAM compiler selector (see
We do understand there is replication between
packages at the
moment, but this will eventually converge as OPAM understands ocamlfind better.
Configuring Mirage Applications
Provided that one and only one file of name
<foo> can be any string) is present in the current working
directory, the command:
$ mirari configure
will configure your project. It will:
- call the right OPAM commands to satisfy dependencies.
To build for the unix-direct target (using tap interfaces), do:
$ mirari configure --unix
To build for the xen target, do:
$ mirari configure --xen
Building Mirage Applications
$ mirari build
will build your project. Likewise, you can use the
switches to build for a particular target.
Running Mirage Applications
$ mirari run (--unix or --xen)
will run the unikernel on the selected backend.
Under the unix-socket backend, it just executes the unikernel.
Under the unix-direct backend (
--unix), mirari 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), mirari creates a xl configuration file and uses
xlto run the unikernel locally. Xen has to be installed and running on the machine.
Compiling to Xen and deploying to the cloud
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.