YungSang / coreos-cluster

CoreOS Cluster Setup with Vagrant

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 [e-mail]: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 ~ $
  

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