"One container to rule them all"
The goal is to spawn a complete dockerized environment,
containing all necessary components for a PaaS,
fully transferable between any kind of development stage: laptop / integration / production,
highly robust, highly available, fail tolerance,
where deployment part is fully independent from a running part.
Services supposed to be spawn in a second, fully scalable, easy to monitor, debug and orchestrate.
- Mesos + Marathon + ZooKeeper (orchestration components)
- Consul (K/V store, monitoring, service directory and registry) + Registrator (automating register/ deregister)
- HAproxy + consul-template (load balancer with dynamic config generation)
This is the default configuration, that starts all components inside container.
It is recommended to run 3 or 5 master containers to ensure high availability of the PasteraS cluster.
Slave mode is enabled by MASTER=false
In this mode starts only slave components, (master part is excluded)
You can run as many slaves as you wish - this is fully scalable.
To connect multiple datacenter use consul join -wan <server 1> <server 2>
Depending on MASTER
and SLAVE
you can define role of the container
daemon\role | default | Only Master | Only Slave |
-----------:|:----------------:|:-----------:|:-------------:|
|MASTER=true
|MASTER=true
| MASTER=false
|
|SLAVE=true
|SLAVE=false
| SLAVE=true
|
Consul| x | x | x |
Mesos Master| x | x | - |
Marathon | x | x | - |
Zookeeper | x | x | - |
Consul-template| x | - | x |
Haproxy | x | - | x |
Mesos Slave | x | - | x |
Registrator| x | - | x |
dnsmasq| x | x | x |
# vagrant up
or
# IP=192.168.1.1 ./generate_yml.sh
# docker-compose up -d
everyhost# cd panteras
everyhost# mkdir restricted
everyhost# echo 'ZOOKEEPER_HOSTS="masterhost-1:2181,masterhost-2:2181,masterhost-3:2181"' >> restricted/host
everyhost# echo 'CONSUL_HOSTS="-join=masterhost-1 -join=masterhost-2 -join=masterhost-3"' >> restricted/host
masterhost-1# echo "ZOOKEEPER_ID=1" >> restricted/host
masterhost-2# echo "ZOOKEEPER_ID=2" >> restricted/host
masterhost-3# echo "ZOOKEEPER_ID=3" >> restricted/host
masterhost-n# ./generate_yml.sh
masterhost-n# docker-compose up -d
slavehost-n# MASTER=false ./generate_yml.sh
slavehost-n# docker-compose up -d
You can reach the PaaS components on the following ports:
- HAproxy: http://hostname:81
- Consul: http://hostname:8500
- Marathon: http://hostname:8080
- Mesos: http://hostname:5050
- Supervisord: http://hostname:9000
You might want to access the PaaS and services with your browser directly via service name like:
http://your_service.service.consul
This could be problematic. It depends where you run docker host. We have prepared two services that might help you solving this problem.
DNS - which supposed to be running on every docker host, it is important that you have only one DNS server occupying port 53 on docker host, you might need to disable yours, if you have already configured.
If you have direct access to the docker host DNS, then just modify your /etc/resolv.conf adding its IP address.
If you do NOT have direct access to docker host DNS, then you have two options:
A. use OpenVPN client an example server we have created for you (in optional), but you need to provide certificates and config file, it might be little bit complex for the beginers, so you might to try second option first.
B. SSHuttle - use https://github.com/apenwarr/sshuttle project so you can tunnel DNS traffic over ssh but you have to have ssh daemon running in some container.
$ cd examples/SimpleWebappPython
$ ./build-docker-image.sh
$ ./start_with_marathon.sh
which gonna spawn 4 containers described in deploy1_marathon.json
and deploy2_marathon.json
2 services with 2 instances each, that can be accessed for humans via browser:
http://python1.service.consul
http://python2.service.consul
HAproxy gonna ballance services between ports,
which has been mapped and assigned by marathon.
For non human access, like services intercommunication, you can use direct access using DNS consul SRV abilities, to verify answers:
$ dig python1.service.consul +tcp SRV
or asking consul DNS directly:
$ dig @$CONSUL_IP -p8600 python1.service.consul +tcp SRV
remmeber to disable DNS caching in your future services.
[1] https://www.docker.com/
[2] http://docs.docker.com/compose/
[3] http://stackoverflow.com/questions/25217208/setting-up-a-docker-fig-mesos-environment
[4] http://www.consul.io/docs/