InstallationTanka

Install Loki with Tanka

Tanka is a reimplementation of Ksonnet that Grafana Labs created after Ksonnet was deprecated. Tanka is used by Grafana Labs to run Loki in production.

Prerequisites

Install the latest version of Tanka (at least version v0.5.0) for the tk env commands. Prebuilt binaries for Tanka can be found at the Tanka releases URL.

In your config repo, if you don’t have a Tanka application, create a folder and call tk init inside of it. Then create an environment for Loki and provide the URL for the Kubernetes API server to deploy to (e.g., https://localhost:6443):

mkdir <application name>
cd <application name>
tk init
tk env add environments/loki --namespace=loki --server=<Kubernetes API server>

Deploying

Download and install the Loki and Promtail module using jb:

go get -u github.com/jsonnet-bundler/jsonnet-bundler/cmd/jb
jb init  # not required if you already ran `tk init`
jb install github.com/grafana/loki/production/ksonnet/loki
jb install github.com/grafana/loki/production/ksonnet/promtail

Note: As of 2020-08-13, we use some features that are not yet generally available. This step will be unnecessary in future Tanka releases. For now, install this library, which we’ll use as an override:

jb install github.com/jsonnet-libs/k8s-alpha/1.14

Next, override the lib/k.libsonnet with the following

(import 'github.com/jsonnet-libs/k8s-alpha/1.14/main.libsonnet')
+ (import 'github.com/jsonnet-libs/k8s-alpha/1.14/extensions/kausal-shim.libsonnet')

Be sure to replace the username, password, and the relevant htpasswd contents. Making sure to set the value for username, password, and htpasswd properly, replace the contents of environments/loki/main.jsonnet with:

local gateway = import 'loki/gateway.libsonnet';
local loki = import 'loki/loki.libsonnet';
local promtail = import 'promtail/promtail.libsonnet';

loki + promtail + gateway {
  _config+:: {
    namespace: 'loki',
    htpasswd_contents: 'loki:$apr1$H4yGiGNg$ssl5/NymaGFRUvxIV1Nyr.',

    // S3 variables remove if not using aws
    storage_backend: 's3,dynamodb',
    s3_access_key: 'key',
    s3_secret_access_key: 'secret access key',
    s3_address: 'url',
    s3_bucket_name: 'loki-test',
    dynamodb_region: 'region',

    // GCS variables remove if not using gcs
    storage_backend: 'bigtable,gcs',
    bigtable_instance: 'instance',
    bigtable_project: 'project',
    gcs_bucket_name: 'bucket',

    promtail_config+: {
      clients: [{
        scheme:: 'http',
        hostname:: 'gateway.%(namespace)s.svc' % $._config,
        username:: 'loki',
        password:: 'password',
        container_root_path:: '/var/lib/docker',
      }],
    },

    replication_factor: 3,
    consul_replicas: 1,
  },
}

Notice that container_root_path is your own data root for the Docker Daemon. Run docker info | grep "Root Dir" to get the root path.

Run tk show environments/loki to see the manifests that will be deployed to the cluster. Run tk apply environments/loki to deploy the manifests.