fleeting-plugin-openstack

GitLab fleeting plugin for OpenStack.

https://docs.gitlab.com/runner/executors/docker_autoscaler.html

Plugin Configuration

The following parameters are supported:

Parameter	Type	Description
cloud	string	Name of the cloud config from clouds.yaml to use
clouds_config	string	Optional. Path to clouds.yaml
name	string	Name of the Auto Scaling Group (unique string that used to find instances)
nova_microversion	string	Optional. Microversion for the Openstack Nova client. Default 2.79 (which should be ok for Train+)
boot_time	string	Optional. Maximum wait time for instance to boot up. During that time plugin check Cloud-Init signatures.
use_ignition	string	Enable Fedora CoreOS / Flatcar Linux Ignition support
server_spec	object	Server spec used to create instances. See: Compute API

Default connector config

Parameter	Default
os	linux
protocol	ssh
username	unset
use_static_credentials	false

OpenStack setup

1. You should create a special user (recommended) and project (optional), then export clouds.yaml with credentials for that cloud.

2. You may create a tenant network for workers, in that case don't forget to add a router. In that case manager VM should have two ports: external and that tenant network, so it will be able to connect to the worker instances.

3. You should upload a special image with container runtime installed in it. For example we use Flatcar Linux

4. (Optional) You should generate SSH keypair which will be used by manager instance to connect to workers. Public key must be added to Nova from the user.

   Note: that key required only for Cloud-Init based images. For a Flatcar plugin can generate dynamic ssh key and pass it via Ignition script.

Preparation of the resources could be done by Heat using heat/stack.yaml. But consider it as an example.

Example runner config

concurrent = 16
check_interval = 0
shutdown_timeout = 0
log_level = "info"

[session_server]
session_timeout = 1800
listen_address = ":8093"
advertise_address = "mgr.scalingrunner.cloud:8093"

[[runners]]
name = "manager"
url = "https://gitlab.com"
token = "token"
executor = "docker-autoscaler"
output_limit = 10240
shell = "bash"
environment = [
  "FF_NETWORK_PER_BUILD=1"
  ]

[runners.cache]
Type = "s3"
Shared = true

[runners.cache.s3]
ServerAddress = "s3.foo.bar"
AccessKey = "access"
SecretKey = "secret"
BucketName = "cache"

[runners.docker]
disable_entrypoint_overwrite = false
oom_kill_disable = false
disable_cache = true
shm_size = 0
network_mtu = 0
# host = "unix:///run/user/1000/podman/podman.sock"
# tls_verify = false
# image = "quay.io/podman/stable"
image = "almalinux:9"
privileged = true
pull_policy = ["always", "always"]

[runners.autoscaler]
capacity_per_instance = 1
max_use_count = 10
max_instances = 16
plugin = "fleeting-plugin-openstack"

[runners.autoscaler.plugin_config]
cloud = "runner"
clouds_config = "/etc/gitlab-runner/clouds.yaml"
name = "scaling-runner-stack-id"
nova_microversion = "2.79" # train+
boot_time = "10m"
use_ignition = true  # enable injection of dynamic SSH key into Ignition config

[runners.autoscaler.plugin_config.server_spec]
name = "scaling-runner-%d"                                               # %d replaced with instance index
description = "GitLab CI Docker runners with autoscaling"
tags = ["GitLab", "CI", "Docker", "Scaling"]
imageRef = "d5460af5-83f3-47d7-9c4f-80294c66b267"                       # Flatcar Linux
flavorRef = "4e9d4fa4-a703-4850-8bc1-58b5e139ab57"                      # xlarge flavor
# key_name = "ci-admin"                                                 # SSH public key for worker nodes
networks = [ { uuid = "f05e7f64-9e0f-4c5c-acb0-b636000d7301" } ]        # tenant network
security_groups = [ "cee22d91-bb9a-455d-be88-e911d3cb066a" ]            # allow SSH ingress from tenant network
scheduler_hints = { group = "a9c941cb-5b34-46e0-8fc6-7471e3b77c75" }    # [Soft-]Anti-Affinity group
# May be used to pass #cloud-config or ignition scripts.
# If use_ignition == true, plugin will try parse existing script to inject passwd.users entry.
# user_data = ''''''

[runners.autoscaler.connector_config]
# username = "fedora"                    # Can be extracted from Image metadata os_admin_user
# password = ""                          # not used
# key_path = "/etc/gitlab-runner/id_rsa" # private key passed to server_spec.key_name. Required in cloud-init mode, optional for Ignition.
# use_static_credentials = true          # Tells to use key provided above.
keepalive = "30s"
timeout = "0m"
use_external_addr = false

[[runners.autoscaler.policy]]
idle_count = 2
idle_time = "30m0s"
scale_factor = 0.0
scale_factor_limit = 0