IT Cloud. Eugeny Shtoltc
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of the microservice application bookinfo, which is part of Istio as an example: https://github.com/istio/istio/tree/master/samples/bookinfo. The demo will be at www.katacoda.com/courses/istio/deploy-istio-on-kubernetes. After deployment, it will be available
Infrastructure management
Although Kubernetes also has its own graphical interface – a UI dashboard, it does not provide other than monitoring and simple actions. More possibilities are given by OpenShift, providing a combination of graphic and text creation. A full-fledged product with a formed Google ecosystem in Kubernetes does not provide, but provides a cloud solution – Google Cloud Platform. However, there are third-party solutions, such as Open Shift and Rancher, that allow you to use it fully through a graphical interface at its own facilities. If desired, of course, you can sync with the cloud.
Each product is often not API compatible with each other, the only known exception being Mail. Cloud, which claims support for Open Shift. But, there is a third-party solution that implements the infrastructure as code approach and supports the API of most well-known ecosystems – Terraform. He, like Kubernetes, applies the concept of infrastructure as code, but not to containerization, but to virtual machines (servers, networks, disks). The Infrastructure as Code principle implies a declarative configuration – that is, a description of the result without explicitly specifying the actions themselves. Upon activation, the configuration (in Kubernetes it is kubectl apply -f name_config .yml , and in Hashicorp Terraform it is terraform apply ) of the system is brought into line with the configuration files, when the configuration or infrastructure changes, the infrastructure in the conflicting parts is brought into line with its declaration, when the system itself decides how to achieve this, and the behavior can be different, for example, when the meta information in the POD changes, it will be changed, and when the image changes, the POD will be deleted and created as a new one. If, before that, we created the server infrastructure for containers in an imperative form using the gcloud command of the Google Cloud Platform (GCP) public cloud, now we will consider how to create a similar configuration using the configuration in the declarative description of the pattern infrastructure as code using the universal Terraform tool that supports cloud GCP.
Terraform did not appear out of nowhere, but became a continuation of the long history of the emergence of software products for configuring and managing server infrastructure, I will list in the order of appearance and transition:
** CFN;
** Pupet;
** Chef;
** Ansible;
** Cloud AWS API, Kubernetes API;
* IasC: Terraform does not depend on the type of infrastructure (it supports more than 120 providers, including not only clouds), in contrast to the bucket counterparts that support only themselves: CloudFormation for Amazon WEB Service, Azure Resource Manager for Microsoft Azure, Google Cloud Deployment Manager from Google Cloud Engine.
CloudFormation is built by Amazon and is intended to be worthless, and is also fully integrated into the CI / CD of its infrastructure hosted on AWS S3, which makes GIT versioning difficult. We will consider a platform independent Terraform: the syntax of the basic functionality is the same, and the specific one is connected through the Providers entities (https://www.terraform.io/docs/providers/index.html). Terraform is one binary file, supports a huge number of providers, and of course AWS and GCE. Terraform, like most products from Hashicorp, is written in Go and is a single binary executable file, does not require installation, you just need to download it to the Linux folder:
(agile-aleph-203917) $ wget https://releases.hashicorp.com/terraform/0.11.13/terraform_0.11.13_linux_amd64.zip
(agile-aleph-203917) $ unzip terraform_0.11.13_linux_amd64.zip -d.
(agile-aleph-203917) $ rm -f terraform_0.11.13_linux_amd64.zip
(agile-aleph-203917) $ ./terraform version
Terraform v0.11.13
It supports splitting into modules that you can write yourself or use ready-made ones (https://registry.terraform.io/browse?offset=27&provider=google). To orchestrate and support changes in dependencies, you can use Terragrunt (https://davidbegin.github.io/terragrunt/), for example:
terragrant = {
terraform {
source = "terraform-aws-modules / …"
}
dependencies {
path = ["..network"]
}
}
name = "…"
ami = "…"
instance_type = "t3.large"
Unified semantics for different providers (AWS, GCE, Yandex. Cloud and many others) configurations, which allows you to create a transcendental infrastructure, for example, permanently loaded services are located to save on their own capacities, and are variably loaded (for example, during the promotional period) in public clouds … Due to the fact that management is declarative and can be described by files (IaC, infrastructure as code), the creation of infrastructure can be added to the CI / CD pipeline (development, testing, delivery, everything is automatic and with version control). Without CI / CD, config file locking is supported to prevent concurrent editing when working together. the infrastructure is not created by a script, but is brought into conformity with the configuration, which is declarative and cannot contain logic, although it is possible to inject BASH scripts into it and use Conditions (term operator) for different environments.
Terraform will read all files in the current directory with a .tf extension in the Hachicort Configuraiton Language (HCL) format or .tf format . json in JSON format. Often, instead of one file, it is divided into several, at least two: the first containing the configuration, the second – private data in variables.
To demonstrate Terraform's capabilities, we will create a GitHub repository due to its ease of authorization and API. First, we get a token generated in the WEB interface: SettingsDeveloper sittings -> Personal access token -> Generate new token and setting permissions. We will not create anything, just check the connection:
(agile-aleph-203917) $ ls * .tf
main.tf variables.tf
$ cat variables.tf
variable "github_token" {
default = "630bc9696d0b2f4ce164b1cabb118eaaa1909838"
}
$ cat main.tf
provider "github" {
token = "$ {var.github_token}"
}
(agile-aleph-203917) $ ./terraform init
(agile-aleph-203917) $ ./terraform apply
Apply complete! Resources: 0 added, 0 changed, 0 destroyed.
Now, let's create a manager account Settings -> Organizations -> New organization -> Create organization. … Using: Terraform Repository API www.terraform.io/docs/providers/github/r/repository. html add a description of the repository to the config:
(agile-aleph-203917) $ cat main.tf
provider "github" {
token = "$ {var.github_token}"
}
resource "github_repository" "terraform_repo" {
name = "terraform-repo"
description = "my terraform repo"
auto_init = true
}
Now it remains to apply, look at the plan for creating a repository, agree with it:
(agile-aleph-203917) $ ./terraform apply
provider.github.organization
The GitHub organization name to manage.
Enter a value: essch2
An execution plan has been generated and is shown below.
Resource actions are indicated with the following symbols:
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