CoreOS Cluster Setup with Vagrant

This will setup CoreOS cluster environment with Vagrant.

$ git clone https://github.com/YungSang/coreos-cluster
$ cd coreos-cluster
$ make virtualbox

in case you are using parallels...

$ make parallels

By default a three node cluster is provisioned, consuming CoreOS default, production, channel.

If you wish to change the defaults just edit cluster.yaml and modify it to suit your goals.

Play with Etcd

Requirement: etcdctl
Check Etcd status
```
 $ etcdctl ls
```
You may need the following configurations.
```
 $ export ETCDCTL_PEERS="$(vagrant ssh-config core-1 | sed -n "s/[ ]*HostName[ ]*//gp"):4001"
```
etcdctl < v0.4.5
```
 $ etcdctl -C "${ETCDCTL_PEERS}" ls
```
etcdctl >= v0.4.5 supports ETCDCTL_PEERS env variable
Cf.) https://github.com/coreos/etcdctl/pull/95/files

Test writing and reading

 $ etcdctl set /services/test test
 $ etcdctl ls --recursive
 /services
 /services/test
 $ etcdctl get /services/test
 test
 $ vagrant ssh core-3 -c "etcdctl get /services/test"
 test

Play with Fleet

Cf.) Controlling the Cluster with fleetctl

Requirement: fleetctl

Prepare

You may need to reset ~/.fleetctl/known_hosts.

 $ rm ~/.fleetctl/known_hosts

You may need the following configurations.

 $ vagrant ssh-config core-1 | sed -n "s/IdentityFile//gp" | xargs ssh-add
 $ export FLEETCTL_TUNNEL="$(vagrant ssh-config core-1 | sed -n "s/[ ]*HostName[ ]*//gp"):$(vagrant ssh-config core-1 | sed -n "s/[ ]*Port[ ]*//gp")"

Cf.) Remote fleet Access for Vagrant

Check Fleet status

 $ fleetctl list-machines
 MACHINE		IP				METADATA
 d760866b...	192.168.65.2	-
 6d1a752c...	192.168.65.3	-
 39959ae3...	192.168.65.4	-
 $ fleetctl list-units
 UNIT	LOAD	ACTIVE	SUB		DESC	MACHINE

Deplay hello.service

 $ curl -LO https://raw.github.com/coreos/fleet/master/examples/hello.service
 $ fleetctl submit hello.service
 $ fleetctl list-units
 UNIT			LOAD	ACTIVE	SUB	DESC		MACHINE
 hello.service	-		-		-	Hello World	-
 $ fleetctl start hello.service
 $ fleetctl list-units
 UNIT			LOAD	ACTIVE	SUB		DESC		MACHINE
 hello.service	loaded	active	running	Hello World	d760866b.../192.168.65.2

Check the status and login to the VM where the servise runs

 $ fleetctl status hello.service
 hello.service - Hello World
    Loaded: loaded (/run/systemd/system/hello.service; enabled-runtime)
    Active: active (running) since Sat 2014-03-29 16:10:17 UTC; 58s ago
  Main PID: 3237 (bash)
    CGroup: /system.slice/hello.service
            ├─3237 /bin/bash -c while true; do echo "Hello, world"; sleep 1; done
            └─3305 sleep 1

 Mar 29 16:11:06 core-1 bash[3237]: Hello, world
 Mar 29 16:11:07 core-1 bash[3237]: Hello, world
 Mar 29 16:11:08 core-1 bash[3237]: Hello, world
 Mar 29 16:11:09 core-1 bash[3237]: Hello, world
 Mar 29 16:11:10 core-1 bash[3237]: Hello, world
 Mar 29 16:11:11 core-1 bash[3237]: Hello, world
 Mar 29 16:11:12 core-1 bash[3237]: Hello, world
 Mar 29 16:11:13 core-1 bash[3237]: Hello, world
 Mar 29 16:11:14 core-1 bash[3237]: Hello, world
 Mar 29 16:11:15 core-1 bash[3237]: Hello, world
 $ fleetctl ssh -unit hello.service
    ______                ____  _____
   / ____/___  ________  / __ \/ ___/
  / /   / __ \/ ___/ _ \/ / / /\__ \
 / /___/ /_/ / /  /  __/ /_/ /___/ /
 \____/\____/_/   \___/\____//____/
 core@core-1 ~ $

Ambassador Pattern

Cf.) Dynamic Docker links with an ambassador powered by etcd

Clear the previous service unit

 $ fleetctl destroy hello.service
 $ fleetctl list-units
 UNIT	LOAD	ACTIVE	SUB		DESC	MACHINE

Get services for Ambassador Pattern

 $ git clone git@github.com:YungSang/fleet-redis-demo.git ambassador

Deploy service units with Fleet

 $ fleetctl start ambassador/*.service
 $ fleetctl list-units
 UNIT						LOAD	ACTIVE	SUB		DESC					MACHINE
 etcd-amb-redis.service		loaded	active	running	Ambassador on A			a7175ced.../192.168.65.2
 etcd-amb-redis2.service		loaded	active	running	Ambassador on B			bbeb5e27.../192.168.65.3
 redis-demo.service			loaded	active	running	Redis on A				a7175ced.../192.168.65.2
 redis-docker-reg.service	loaded	active	running	Register on A			a7175ced.../192.168.65.2
 redis-dyn-amb.service		loaded	active	running	Etcd Ambassador on B	bbeb5e27.../192.168.65.3

Make sure the services has been started successfully (It will take some time to complete.)

 $ etcdctl ls --recursive
 /services
 /services/redis-A
 /services/redis-A/redis-demo.service
 $ etcdctl get /services/redis-A/redis-demo.service
 { "port": 49153, "host": "192.168.65.2" }

Check links from Host B to Redis on Host A

 $ fleetctl ssh -unit redis-dyn-amb.service
    ______                ____  _____
   / ____/___  ________  / __ \/ ___/
  / /   / __ \/ ___/ _ \/ / / /\__ \
 / /___/ /_/ / /  /  __/ /_/ /___/ /
 \____/\____/_/   \___/\____//____/
 core@core-2 ~ $ docker run -i -t --link redis-dyn-amb.service:redis shopigniter/redis-cli -h redis
 Pulling repository shopigniter/redis-cli
 .
 .
 .
 redis:6379> ping
 PONG
 redis:6379> exit
 core@core-2 ~ $

License

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