6.4 KiB
Running custom executors on Aurora
In this instance we will be using the docker-compose executor to demonstrate how Aurora can use multiple executors on a single Scheduler.
Configuring Scheduler to use Docker-Compose executor
In order use the docker compose executor with Aurora, we must first give the scheduler a configuration file that contains information on how to run the executor.
Configuration file
The configuration is a JSON file that contains where to find the executor and how to run it.
A sample config file for the docker-compose executor looks like this:
[
{
"executor":{
"command":{
"value":"java -jar docker-compose-executor_0.0.1.jar",
"shell":"true",
"uris":[
{
"cache":false,
"executable":true,
"extract":false,
"value":"https://dl.bintray.com/rdelvalle/mesos-compose-executor/docker-compose-executor_0.0.1.jar"
}
]
},
"name":"docker-compose-executor",
"resources":[]
},
"task_prefix":"compose-"
}
]
Configuring Scheduler to run custom executor
Setting the proper flags -custom_executor_config flag and enabling mesos fetcher on jobs
The --custom_executor_config flag must point to the location of the JSON blob.
The --enable_mesos_fetcher flag must be set to true in order to allow jobs to fetch resources.
On vagrant
Modify the file /etc/init/aurora-scheduler.conf to include:
--custom_executor_config=<Location of JSON blob> \
--enable_mesos_fetcher=true
On a scheduler installed via package manager
Modify the file /etc/default/aurora-scheduler.conf to include:
AURORA_EXTRA_ARGS="--custom_executor_config=<Location of JSON blob> \
--enable_mesos_fetcher=true"
Using a custom client
Pystachio does yet support launching tasks using a custom executors. Therefore, a custom client must be used in order to launch tasks using a custom executor. In this case, we will be using gorealis to launch a task with the compose executor on Aurora.
Configuring the system to run the custom client and docker-compose executor
Installing Go
Linux
Ubuntu
Add PPA and install via apt-get
$ sudo add-apt-repository ppa:ubuntu-lxc/lxd-stable
$ sudo apt-get update
$ sudo apt-get install golang
Set GOPATH
Configure the environment to be able to compile and run Go code.
$ mkdir $HOME/go
$ echo export GOPATH=$HOME/go >> $HOME/.profile
$ echo export PATH=$PATH:$GOPATH/bin >> $HOME/.profile
$ echo export PATH=$PATH:$GOROOT/bin >> $HOME/.profile
OS X
One way to install go on OS X is by using Homebrew
Install Homebrew
Run the following command from the terminal to install Hombrew:
$ /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
Install Go using Hombrew
Run the following command from the terminal to install Go:
$ brew install go
Set the GOPATH
Configure the environment to be able to compile and run Go code.
$ mkdir $HOME/go
$ echo export GOPATH=$HOME/go >> $HOME/.profile
$ echo export GOROOT=/usr/local/opt/go/libexec >> $HOME/.profile
$ echo export PATH=$PATH:$GOPATH/bin >> $HOME/.profile
$ echo export PATH=$PATH:$GOROOT/bin >> $HOME/.profile
Windows
Download and run the msi installer from https://golang.org/dl/
Installing Docker Compose
In order to run the docker-compose executor, each agent must have docker-compose installed on it.
This can be done using pip:
$ sudo pip install docker-compose
Downloading gorealis
Finally, we must get gorealis using the go get command:
go get github.com/rdelval/gorealis
Creating Aurora Jobs
Creating a thermos job
To demonstrate that we are able to run jobs using different executors on the same scheduler, we'll first launch a thermos job using the default Aurora Client.
We can use a sample job for this:
hello_world.aurora
hello = Process(
name = 'hello',
cmdline = """
while true; do
echo hello world
sleep 10
done
""")
task = SequentialTask(
processes = [hello],
resources = Resources(cpu = 1.0, ram = 128*MB, disk = 128*MB))
jobs = [Service(
task = task, cluster = 'devcluster', role = 'www-data', environment = 'prod', name = 'hello')]
Now we create the job:
aurora job create devcluster/www-data/prod/hello hello_world.aurora
Creating a docker-compose-executor job
Now that we have a thermos job running, it's time to launch a docker-compose job.
We'll be using the gorealis library sample client to send a create job request to the scheduler, specifiying that we would like to use the docker-compose executor.
Furthermore, we will be specifying what resources we need to download in order to successfully run a docker compose job.
The job configuration in the sample client looks like this:
job = realis.NewJob().
Environment("prod").
Role("vagrant").
Name("docker-compose").
ExecutorName("docker-compose-executor").
ExecutorData("{}").
CPU(1).
Ram(64).
Disk(100).
IsService(false).
InstanceCount(1).
AddPorts(1).
AddLabel("fileName", "sample-app/sample-app.yml").
AddURI("https://dl.bintray.com/rdelvalle/mesos-compose-executor/sample-app.tar.gz", true, true)
Now we run the client sending the create job command to Aurora:
go run $GOPATH/src/github.com/rdelval/gorealis/examples/Client.go -executor=compose -url=http://192.168.33.7:8081 -cmd=create
If everything went according to plan, a new job will be shown in the Aurora UI.
We can further investigate inside the Mesos task sandbox.
Inside the sandbox, under the sample-app folder, we can find a docker-compose.yml-generated.yml.
If we inspect this file, we can find the port at which we can find the web server we launched.
Under Web->Ports, we find the port Mesos allocated. We can then navigate to:
<agent address>:<assigned port>
And a message from the executor should greet us.
Cleaning up
Using the Default Client
$ aurora job killall devcluster/www-data/prod/hello
$ aurora job killall devcluster/vagrant/prod/docker-compose
Using gorealis
$ go run $GOPATH/src/github.com/rdelval/gorealis/examples/Client.go -executor=compose -url=http://192.168.33.7:8081 -cmd=kill
$ go run $GOPATH/src/github.com/rdelval/gorealis/examples/Client.go -executor=thermos -url=http://192.168.33.7:8081 -cmd=kill