consul-lb-gce

A smart Google Cloud Engine load-balancer manager for Consul backed services.

• 1. Pre-requisites
• 2. Development
  • 2.1. Build
  • 2.2. Test
  • 2.3. Scaling

1. Pre-requisites

• Go 1.5.x

• make

• Some Go tools

  • gb - go get -u github.com/constabulary/gb/…​

• A running Nomad cluster with Consul integration on Google Compute Engine

2. Development

2.1. Build

The following will take care of generating code, build and run tests.

make all

2.2. Test

Attention: Testing locally is not supported, but if you’re feeling adventurous, take a look at this Nomad cluster with Consul integration.

Now, before deploying the nginx service example, let’s compile and run the load-balancer manager. On another terminal window, execute:

gb build all
cat config.toml.sample > config.toml

(..edit config.toml accordingly..)

GOOGLE_APPLICATION_CREDENTIALS=~/Work/gce/my-project-1234567890.json bin/consul-lb-google -config config.toml -alsologtostderr

You should see something like:

I1218 16:20:36.877575       1 main.go:45] Starting..
I1218 16:20:36.877909       1 main.go:54] Initializing cloud client [Project ID: my-project, Network: my-network, Allowed Zones: []string{"us-east1-d", "europe-west1-d", "asia-east1-c"}]..
I1218 16:20:36.878178       1 main.go:61] Connecting to Consul at consul.service.consul:8500..
I1218 16:20:36.878198       1 main.go:69] Initiating registry..
I1218 16:20:36.878214       1 main.go:76] Waiting for service updates..

Deploy the nginx example:

nomad run web.hcl

Looking at the load-balancer manager terminal window, one should see something like:

I1218 16:21:07.931230       1 main.go:129] Initializing service [web]..
I1218 16:21:07.931263       1 cloud.go:78] Creating instance groups for [web]..
I1218 16:21:07.931269       1 cloud.go:81] Creating instance group [us-east1-d-web] in zone [us-east1-d].
I1218 16:21:11.751202       1 cloud.go:81] Creating instance group [europe-west1-d-web] in zone [europe-west1-d].
I1218 16:21:15.747546       1 cloud.go:81] Creating instance group [asia-east1-c-web] in zone [asia-east1-c].
I1218 16:21:19.653728       1 cloud.go:101] Created instance groups for [web] successfully
I1218 16:21:19.653771       1 main.go:135] Watching service [web].
W1218 16:21:19.653780       1 main.go:195] Adding instance [client-us-01.c.my-project.internal].
I1218 16:21:19.654187       1 main.go:203] Service has new port [11080]
I1218 16:21:19.654217       1 cloud.go:133] Adding 1 instances into instance group [web]
I1218 16:21:19.963843       1 cloud.go:182] There are 1 instances to add to instance group [web] on zone [us-east1-d]. Adding..
I1218 16:21:20.764763       1 cloud.go:187] There are no instances to add to instance group [web] on zone [europe-west1-d].
I1218 16:21:21.049794       1 cloud.go:187] There are no instances to add to instance group [web] on zone [asia-east1-c].
I1218 16:21:21.049813       1 cloud.go:191] Added 1 instances into instance group [web]
I1218 16:21:21.049820       1 cloud.go:244] Setting instance group [web] port [11080]..
I1218 16:21:22.229671       1 cloud.go:266] Creating/updating load-balancer for [web:11080].
I1218 16:21:53.131003       1 gce.go:546] Created/updated firewall rule with success.
I1218 16:21:56.995704       1 gce.go:557] Created/updated HTTP health-check with success.
I1218 16:22:02.429513       1 gce.go:568] Created/updated backend service with success.
I1218 16:22:06.350711       1 gce.go:574] Created URL map with success.
I1218 16:22:10.381194       1 gce.go:580] Created target HTTP proxy with success.
I1218 16:22:17.401182       1 gce.go:587] Created global forwarding rule with success.
I1218 16:22:17.401215       1 cloud.go:268] Load-balancer [web] created successfully.

Validate that load-balancing is working alright.

Now, stop it:

nomad stop web

Looking again at the load-balancer manager terminal window, one should see something like:

I1218 16:26:17.601174       1 cloud.go:273] Removing load-balancer for [web].
I1218 16:26:24.390783       1 gce.go:598] Removed global forwarding rule with success.
I1218 16:26:28.139698       1 gce.go:604] Removed target HTTP proxy with success.
I1218 16:26:32.001725       1 gce.go:610] Removed URL map with success.
I1218 16:26:35.774544       1 gce.go:616] Removed backend service with success.
I1218 16:26:39.477543       1 gce.go:622] Removed HTTP health-check with success.
I1218 16:27:07.202854       1 gce.go:628] Removed firewall rule with success.
I1218 16:27:07.202878       1 cloud.go:275] Load-balancer [web] removed successfully.
I1218 16:27:07.202886       1 cloud.go:109] Removing instance groups for [web]..
W1218 16:27:10.853607       1 cloud.go:115] Removed instance group [us-east1-d-web] from zone [us-east1-d].
W1218 16:27:14.319410       1 cloud.go:115] Removed instance group [europe-west1-d-web] from zone [europe-west1-d].
W1218 16:27:18.036865       1 cloud.go:115] Removed instance group [asia-east1-c-web] from zone [asia-east1-c].
I1218 16:27:18.036888       1 cloud.go:127] Removing instance groups for [web] completed successfully
I1218 16:27:18.036896       1 main.go:149] Stopped watching service [web].

2.3. Scaling

The manager supports scaling the number of instances of a service as well.