cf-bigip-ctlr

README

F5 BIG-IP Controller for Cloud Foundry

The F5 BIG-IP Controller for Cloud Foundry makes the F5 BIG-IP [Local Traffic Manager](<https://f5.com/products/big-ip/local-traffic-manager-ltm) services available to applications running in the Cloud Foundry platform.

Documentation

For instructions on how to use this component, use the F5 BIG-IP Controller for Cloud Foundry docs.

For guides on this and other solutions for Cloud Foundry, see the F5 Solution Guides for Cloud Foundry.

Running

The official docker image is f5networks/cf-bigip-ctlr.

Usually, the controller is deployed in Cloud Foundry. However, the controller can be run locally for development testing. The controller requires a running NATS server, without a valid connection the controller will not start. The controller can either be run against a gnatsd server or standalone against a Cloud Foundry installation.

Option gnatsd:

• Go should be installed and in the PATH
• GOPATH should be set as described in http://golang.org/doc/code.html
• Pip install the python/cf-runtime-requirements.txt into a virtualenv of your choice

workon cf-bigip-ctlr
pip install -r python/cf-runtime-requirements.txt

• gnatds installed and in the PATH

go get github.com/nats-io/gnatsd
gnatsd &

• Optionally run unit tests

go get github.com/onsi/ginkgo
go get github.com/onsi/gomega
ginkgo -keepGoing -trace -p -progress -r -failOnPending -randomizeAllSpecs -race

• Build and install controller from a cloned cf-bigip-ctlr

go install

• Update BIGIP_CTLR_CFG environment variable for your specific environment as described in "Configuration"
• Run the controller

cf-bigip-ctlr

Option standalone:

• Go should be installed and in the PATH
• GOPATH should be set as described in http://golang.org/doc/code.html
• Pip install the python/cf-runtime-requirements.txt into a virtualenv of your choice

workon cf-bigip-ctlr
pip install -r python/cf-runtime-requirements.txt

• Optionally run unit tests

go get github.com/onsi/ginkgo
go get github.com/onsi/gomega
ginkgo -keepGoing -trace -p -progress -r -failOnPending -randomizeAllSpecs -race

• Build and install controller from a cloned cf-bigip-ctlr

go install

• Update configuration file or BIGIP_CTLR_CFG environment variable for your specific environment as described in "Configuration"
• Run the controller

cf-bigip-ctlr -c [CONFIG_FILE]

Building

The official images are built using docker, but standard go build tools can be used for development purposes as described above.

Official Build

Prerequisites:

• Docker

git clone https://github.com/F5Networks/cf-bigip-ctlr.git
cd cf-bigip-ctlr

# Use docker to build the release artifacts into a local "_docker_workspace" directory and push into docker images
make prod

Alternate, unofficial build

A normal go and godep toolchain can be used as well

Prerequisites:

• go 1.7
• GOPATH pointing at a valid go workspace
• godep (Only needed to modify vendor's packages)
• python
• virtualenv

mkdir -p $GOPATH/src/github.com/F5Networks
cd $GOPATH/src/github.com/F5Networks
git clone https://github.com/F5Networks/cf-bigip-ctlr.git
cd cf-bigip-ctlr

# Building all packages, and run unit tests
make prod

Configuration

When pushing the controller into a Cloud Foundry environment a configuration must be passed via the application manifest. An example manifest is located in the docs/_static/config_examples directory.

Update required sections for environment:

• nats: leave empty for gnatsd otherwise update with CF installed NATS information
• bigip: leave empty if no BIG-IP is required otherwise update with BIG-IP information
• routing_api: only required if routing API access is required (TCP routing with route_mode set to all, or tcp)
• oauth: only required if routing API access is required (TCP routing with route_mode set to all, or tcp)

On startup, the controller will get the BIGIP_CTLR_CFG variable from the environment; setting this variable via an application manifest is required, environment parameters are set in the manifest env section. The controller also supports Cloud Foundry health checks. These can be configured in the manifest fields: health-check-type, and health-check-http-endpoint. In order to configure health checking of the controller use these settings:

health-check-type: http
health-check-http-endpoint: /health

To explore what other settings are available refer to the Cloud Foundry documentation Deploying with Application Manifests.

A minimal configuration manifest to support HTTP routing mode would be written as such (route_mode set to 'http'):

applications:
  - name: cf-bigip-ctlr
    health-check-type: http
    health-check-http-endpoint: /health
    env:
      BIGIP_CTLR_CFG: |
                      bigip:
                        url: https://bigip.example.com
                        user: admin
                        pass: password
                        partition:
                          - example
                        external_addr: 192.168.1.1
                      nats:
                        - host: 192.168.10.1
                          port: 4222
                          user: nats
                          pass: nats-password
                      route_mode: http

If TCP routing is required, the oauth and routing_api sections are required but not the nats section. Set route_mode to 'tcp'.

If both modes are required, the oauth, routing_api, and nats sections are required. Set route_mode to 'all'.

Development

Note: This repository should be imported as github.com/F5Networks/cf-bigip-ctlr.

Dynamic Routing Table

The controller's routing table is updated dynamically via the NATS message bus. NATS can be deployed via BOSH with (cf-release) or standalone using nats-release.

To add or remove a record from the routing table, a NATS client must send register or unregister messages. Records in the routing table have a maximum TTL of 120 seconds, so clients must heartbeat registration messages periodically; we recommend every 20s. Route Registrar is a BOSH job that comes with Routing Release that automates this process.

When deployed with Cloud Foundry, registration of routes for apps pushed to CF occurs automatically without user involvement. For details, see Routes and Domains.

Registering Routes via NATS

When the controller starts, it sends a router.start message to NATS. This message contains an interval that other components should then send router.register on, minimumRegisterIntervalInSeconds. It is recommended that clients should send router.register messages on this interval. This minimumRegisterIntervalInSeconds value is configured through the start_response_delay_interval configuration property. The controller will prune routes that it considers to be stale based upon a seperate "staleness" value, droplet_stale_threshold, which defaults to 120 seconds. The controller will check if routes have become stale on an interval defined by prune_stale_droplets_interval, which defaults to 30 seconds. All of these values are represented in seconds and will always be integers.

The format of the router.start message is as follows:

{
  "id": "some-router-id",
  "hosts": ["1.2.3.4"],
  "minimumRegisterIntervalInSeconds": 20,
  "prunteThresholdInSeconds": 120,
}

After a router.start message is received by a client, the client should send router.register messages. This ensures that the new controller can update its routing table.

If a component comes online after the controller, it must make a NATS request called router.greet in order to determine the interval. The response to this message will be the same format as router.start.

The format of the router.register message is as follows:

{
  "host": "127.0.0.1",
  "port": 4567,
  "uris": [
    "my_first_url.vcap.me",
    "my_second_url.vcap.me"
  ],
  "tags": {
    "another_key": "another_value",
    "some_key": "some_value"
  },
  "app": "some_app_guid",
  "stale_threshold_in_seconds": 120,
  "private_instance_id": "some_app_instance_id",
  "router_group_guid": "some_router_group_guid"
}

stale_threshold_in_seconds is the custom staleness threshold for the route being registered. If this value is not sent, it will default to the controller's default staleness threshold.

app is a unique identifier for an application that the endpoint is registered for.

private_instance_id is a unique identifier for an instance associated with the app identified by the app field.

router_group_guid determines which controllers will register route. Only controllers configured with the matching router group will register the route. If a value is not provided, the route will be registered by all controllers that have not be configured with a router group.

Such a message can be sent to both the router.register subject to register URIs, and to the router.unregister subject to unregister URIs, respectively.

Note: In order to use nats-pub to register a route, you must run the command on the NATS VM. If you are using cf-deployment, you can run nats-pub from any VM.

Documentation

Overview

* Portions Copyright (c) 2017, F5 Networks, Inc.