Vagrant up –no-parallel flag meaning

Do anyone know what exactly vagrant up --no-parallel flag does? I found in the docs that I should use it whenever I am linkink two different containers within same Vagrantfile.

Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
    config.vm.define "a" do |app|
        app.vm.provider "docker" do |d|
   = "a"
            d.image = "a"
    config.vm.define "b" do |app|
        app.vm.provider "docker" do |d|
   = "b"
            d.image = "b"

What should I run if I have Vagrantfile looking like this?

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  • vagrant up a --no-parallel && vagrant up b


    vagrant up a && vagrant up b --no-parallel


    vagrant up --no-parallel


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  • One Solution collect form web for “Vagrant up –no-parallel flag meaning”

    --no-parallel option makes sense when vagrant up is used to bring multiple machines up altogether: that is when Vagrantfile declares multiple machines and vagrant up is either given no machine names or multiple machine names. In this case, if the provider supports this (and yes, Docker provider does indeed), Vagrant will attempt to bring all requested machines up in parallel, unless --no-parallel is given.

    So with Docker provider, when linking containers, one may use --no-paralel when bringing multiple machines up altogether:

    $ vagrant up --no-parallel


    $ vagrant up /regex to match machine names/ --no-parallel

    However, if you bring machines up one-by-one with separate commands, it will have no effect (no harm either) if --no-parallel is specified or not. So one may simply do:

    $ vagrant up a && vagrant up b
    Docker will be the best open platform for developers and sysadmins to build, ship, and run distributed applications.