Próximo: Usando o Guix em uma Máquina Virtual, Anterior: Invoking guix system, Acima: Configuração do sistema [Conteúdo][Índice]
guix deployWe’ve already seen operating-system declarations used to manage a
machine’s configuration locally. Suppose you need to configure multiple
machines, though—perhaps you’re managing a service on the web that’s
comprised of several servers. guix deploy enables you to use
those same operating-system declarations to manage multiple remote
hosts at once as a logical “deployment”.
Nota: The functionality described in this section is still under development and is subject to change. Get in touch with us on guix-devel@gnu.org!
guix deploy file
Such an invocation will deploy the machines that the code within file evaluates to. As an example, file might contain a definition like this:
;; This is a Guix deployment of a "bare bones" setup, with ;; no X11 display server, to a machine with an SSH daemon ;; listening on localhost:2222. A configuration such as this ;; may be appropriate for virtual machine with ports ;; forwarded to the host's loopback interface. (use-service-modules networking ssh) (use-package-modules bootloaders) (define %system (operating-system (host-name "gnu-deployed") (timezone "Etc/UTC") (bootloader (bootloader-configuration (bootloader grub-bootloader) (targets '("/dev/vda")) (terminal-outputs '(console)))) (file-systems (cons (file-system (mount-point "/") (device "/dev/vda1") (type "ext4")) %base-file-systems)) (services (append (list (service dhcp-client-service-type) (service openssh-service-type (openssh-configuration (permit-root-login #t) (allow-empty-passwords? #t)))) %base-services)))) (list (machine (operating-system %system) (environment managed-host-environment-type) (configuration (machine-ssh-configuration (host-name "localhost") (system "x86_64-linux") (user "alice") (identity "./id_rsa") (port 2222)))))
The file should evaluate to a list of machine objects. This example,
upon being deployed, will create a new generation on the remote system
realizing the operating-system declaration %system.
environment and configuration specify how the machine should
be provisioned—that is, how the computing resources should be created and
managed. The above example does not create any resources, as a
'managed-host is a machine that is already running the Guix system
and available over the network. This is a particularly simple case; a more
complex deployment may involve, for example, starting virtual machines
through a Virtual Private Server (VPS) provider. In such a case, a
different environment type would be used.
Do note that you first need to generate a key pair on the coordinator
machine to allow the daemon to export signed archives of files from the
store (veja Invocando guix archive), though this step is automatic on Guix
System:
# guix archive --generate-key
Each target machine must authorize the key of the master machine so that it accepts store items it receives from the coordinator:
# guix archive --authorize < coordinator-public-key.txt
user, in this example, specifies the name of the user account to log
in as to perform the deployment. Its default value is root, but root
login over SSH may be forbidden in some cases. To work around this,
guix deploy can log in as an unprivileged user and employ
sudo to escalate privileges. This will only work if sudo is
currently installed on the remote and can be invoked non-interactively as
user. That is, the line in sudoers granting user the
ability to use sudo must contain the NOPASSWD tag. This can
be accomplished with the following operating system configuration snippet:
(use-modules ... (gnu system)) ;for %sudoers-specification (define %user "username") (operating-system ... (sudoers-file (plain-file "sudoers" (string-append (plain-file-content %sudoers-specification) (format #f "~a ALL = NOPASSWD: ALL~%" %user)))))
For more information regarding the format of the sudoers file,
consult man sudoers.
Once you’ve deployed a system on a set of machines, you may find it useful
to run a command on all of them. The --execute or -x
option lets you do that; the example below runs uname -a on all
the machines listed in the deployment file:
guix deploy file -x -- uname -a
One thing you may often need to do after deployment is restart specific services on all the machines, which you can do like so:
guix deploy file -x -- herd restart service
The guix deploy -x command returns zero if and only if the command
succeeded on all the machines.
You may also wish to roll back configurations on machines to a previous generation. You can do that using the --roll-back or -r option like so:
guix deploy --roll-back file
Below are the data types you need to know about when writing a deployment file.
This is the data type representing a single machine in a heterogeneous Guix deployment.
operating-systemThe object of the operating system configuration to deploy.
environmentAn environment-type describing how the machine should be provisioned.
configuration (default: #f)An object describing the configuration for the machine’s
environment. If the environment has a default configuration,
#f may be used. If #f is used for an environment with no
default configuration, however, an error will be thrown.
This is the data type representing the SSH client parameters for a machine
with an environment of managed-host-environment-type.
host-namebuild-locally? (default: #t)If false, system derivations will be built on the machine being deployed to.
systemThe system type describing the architecture of the machine being deployed
to—e.g., "x86_64-linux".
authorize? (default: #t)If true, the coordinator’s signing key will be added to the remote’s ACL keyring.
port (padrão: 22)user (default: "root")identity (default: #f)If specified, the path to the SSH private key to use to authenticate with the remote host.
host-key (default: #f)This should be the SSH host key of the machine, which looks like this:
ssh-ed25519 AAAAC3Nz… root@example.org
When host-key is #f, the server is authenticated against the
~/.ssh/known_hosts file, just like the OpenSSH ssh client
does.
allow-downgrades? (default: #f)Whether to allow potential downgrades.
Like guix system reconfigure, guix deploy compares the
channel commits currently deployed on the remote host (as returned by
guix system describe) to those currently in use (as returned by
guix describe) to determine whether commits currently in use are
descendants of those deployed. When this is not the case and
allow-downgrades? is false, it raises an error. This ensures you do
not accidentally downgrade remote machines.
safety-checks? (default: #t)Whether to perform “safety checks” before deployment. This includes
verifying that devices and file systems referred to in the operating system
configuration actually exist on the target machine, and making sure that
Linux modules required to access storage devices at boot time are listed in
the initrd-modules field of the operating system.
These safety checks ensure that you do not inadvertently deploy a system that would fail to boot. Be careful before turning them off!
This is the data type describing the Droplet that should be created for a
machine with an environment of digital-ocean-environment-type.
ssh-keyThe path to the SSH private key to use to authenticate with the remote host. In the future, this field may not exist.
tagsA list of string “tags” that uniquely identify the machine. Must be given such that no two machines in the deployment have the same set of tags.
regionA Digital Ocean region slug, such as "nyc3".
sizeA Digital Ocean size slug, such as "s-1vcpu-1gb"
enable-ipv6?Whether or not the droplet should be created with IPv6 networking.
This is the data type describing the server that should be created for a
machine with an environment of hetzner-environment-type. It
allows you to configure deployment to a VPS (virtual private
server) hosted by Hetzner.
allow-downgrades? (default: #f)Whether to allow potential downgrades.
authorize? (default: #t)If true, the public signing key "/etc/guix/signing-key.pub" of the
machine that invokes guix deploy will be added to the operating
system ACL keyring of the target machine.
build-locally? (default: #t)If true, system derivations will be built on the machine that invokes
guix deploy, otherwise derivations are build on the target
machine. Set this to #f if the machine you are deploying from has a
different architecture than the target machine and you can’t build
derivations for the target architecture by other means, like offloading
(veja Usando o recurso de descarregamento) or emulation
(veja Transparent Emulation with QEMU).
delete? (default: #t)If true, the server will be deleted when an error happens in the provisioning phase. If false, the server will be kept in order to debug any issues.
labels (default: '())A user defined alist of key/value pairs attached to the SSH key and the
server on the Hetzner API. Keys and values must be strings,
e.g. '(("environment" . "development")). For more information, see
Labels.
location (default: "fsn1")The name of a location to create the server in. For example, "fsn1" corresponds
to the Hetzner site in Falkenstein, Germany, while "sin" corresponds
to its site in Singapore.
server-type (default: "cx42")The name of the
server
type this virtual server should be created with. For example,
"cx42" corresponds to a x86_64 server that has 8 VCPUs, 16 GB of
memory and 160 GB of storage, while "cax31" to the AArch64
equivalent. Other server types and their current prices can be found
here. The "cpx11"
server type is currently not supported, since its rescue system is too small
to bootstrap a Guix system from.
ssh-keyThe file name of the SSH private key to use to authenticate with the remote host.
When deploying a machine for the first time, the following steps are taken to provision a server for the machine on the Hetzner Cloud service:
Once the server has been provisioned and SSH is available, deployment
continues by delegating it to the managed-host-environment-type.
Servers on the Hetzner Cloud service can be provisioned on the AArch64
architecture using UEFI boot mode, or on the x86_64 architecture using BIOS
boot mode. The (gnu machine hetzner) module exports the
%hetzner-os-arm and %hetzner-os-x86 operating systems that are
compatible with those two architectures, and can be used as a base for
defining your custom operating system.
The following example shows the definition of two machines that are deployed
on the Hetzner Cloud service. The first one uses the %hetzner-os-arm
operating system to run a server with 16 shared vCPUs and 32 GB of RAM on
the aarch64 architecture, the second one uses the
%hetzner-os-x86 operating system on a server with 16 shared vCPUs and
32 GB of RAM on the x86_64 architecture.
(use-modules (gnu machine) (gnu machine hetzner)) (list (machine (operating-system %hetzner-os-arm) (environment hetzner-environment-type) (configuration (hetzner-configuration (server-type "cax41") (ssh-key "/home/charlie/.ssh/id_rsa")))) (machine (operating-system %hetzner-os-x86) (environment hetzner-environment-type) (configuration (hetzner-configuration (server-type "cpx51") (ssh-key "/home/charlie/.ssh/id_rsa")))))
Passing this file to guix deploy with the environment variable
GUIX_HETZNER_API_TOKEN set to a valid Hetzner
API key should provision two machines for you.
Próximo: Usando o Guix em uma Máquina Virtual, Anterior: Invoking guix system, Acima: Configuração do sistema [Conteúdo][Índice]