configuration

README

Ciao configuration

One of ciao's goal is to run on top of a minimal and centralized cluster configuration layer. The configuration package implements a small API for ciao components to fetch and store cluster configuration data and use it to configure themselves.

Overview

Ciao's cluster configuration is stored and fetched from a cluster specific storage backend. The ciao-scheduler is the only component in a ciao cluster that interacts with the configuration backend. As a consequence it needs to be given a configuration URI through its -configuration-uri command line option. The default value for it is file:///etc/ciao/configuration.yaml

The scheduler initially fetches the configuration data by calling configuration.ExtractBlob() but can also get configuration updates from the ciao-controller component after it receives a CONFIGURE command from it.

The scheduler propagates configuration data in 2 ways:

1. Through the initial client connection: The scheduler adds a configuration binary payload (e.g. a marshalled YAML) to the SSNTP CONNECTED frame when a client successfully connected. The client can then fetch the configuration payload by calling configuration.Payload().

2. Through the CONFIGURE command: The ciao-controller can get configuration updates through its HTTPS endpoints and will then send the updated configuration data to the ciao-scheduler by adding it to a SSNTP CONFIGURE command. It is the ciao-scheduler's duty to validate this new configuration data and then forward it to all ciao SSNTP clients by multicasting a CONFIGURE command to all of them.

Backends

The ciao configuration package only implements the logic for fetching, storing, validating and manipulating configuration data. It does not implement configuration physical storage but instead relies on the configuration storage backend.

Currently supported configuration storage backends is:

• Local file: The local file storage URI should follow the file://[absolute path to the configuration file] scheme.

Configuration data

The ciao configuration data follows a [YAML scheme] (https://github.com/ciao-project/ciao/blob/master/payloads/configure.go):

configure:
  scheduler:
    storage_uri: string [The storage URI path]
  storage:
    ceph_id: string [Name used for the Ceph identifier]
  controller:
    compute_port: int
    compute_ca: string [The HTTPS compute endpoint CA]
    compute_cert: string [The HTTPS compute endpoint private key]
    client_auth_ca_cert_path: string [Path to CA to verify client certificates with]
  launcher:
    compute_net: list [The launcher compute network(s)]
    mgmt_net: list [The launcher management network(s)]
    disk_limit: bool
    mem_limit: bool
    child_user: string [ User and group under which launcher's child processes are to run.  If empty they run as the same user as launcher ]

Configuration Examples

Minimal

configure:
  scheduler:
    storage_uri: /etc/ciao/configuration.yaml
  controller:
    compute_ca: /etc/pki/ciao/compute_ca.pem
    compute_cert: /etc/pki/ciao/compute_key.pem
  launcher:
    compute_net:
    - 192.168.0.0/16
    mgmt_net:
    - 192.168.0.0/16

Complete

configure:
  scheduler:
    storage_uri: /etc/ciao/configuration.yaml
  storage:
    ceph_id: ciao
  controller:
    compute_port: 8774
    compute_ca: /etc/pki/ciao/compute_ca.pem
    compute_cert: /etc/pki/ciao/compute_key.pem
  launcher:
    compute_net:
    - 192.168.0.0/16
    mgmt_net:
    - 192.168.0.0/16
    disk_limit: true
    mem_limit: true

Documentation

Index

• func Blob(conf *payloads.Configure) (blob []byte, err error)
• func ExtractBlob(uri string) (blob []byte, err error)
• func Payload(blob []byte) (conf payloads.Configure, err error)

Functions

func Blob

func Blob(conf *payloads.Configure) (blob []byte, err error)

Blob returns an array of bytes containing the cluster configuration.

func ExtractBlob

func ExtractBlob(uri string) (blob []byte, err error)

ExtractBlob returns a configuration payload. It could be used by the SSNTP server or some other entity.

func Payload

func Payload(blob []byte) (conf payloads.Configure, err error)

Payload fills the payloads.Configure struct passed in 'conf' with the values from the bytes given