Google Cloud Monitoring: Restart a process automatically when detecting error - monitoring

I'm using Google Cloud Monitoring (Stackdriver) for endpoing check. It's very useful but I need to restart a process manually after receiving an alert. Does anybody have any good idea?
update1
monit looks nice.
https://mmonit.com/monit/

http://supervisord.org/ is an option which is preferred by various developers but there is no such default solution to my knowledge.
It would be a great feature for stackdriver though. Whenever it detects a failure it can run a failsafe script on the machine as a privileged user.

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Tasks will not run in Spring Cloud Data Flow (Docker/K8S)

Last week I installed the Docker/Kubernetes based version of Spring Cloud Data Flow
Although there were not overt errors, things are not working correctly.
I am able to create streams and tasks in the web UI and Spring Cloud Data Flow Shell but nothing runs.
I am most interested in Tasks.
When I create them, they all show with a Task Status of UNKNOWN.
Unfortunately, no matter how many times I launch them, the status always remains UNKNOWN.
I'm able to delete them but what magic must I use to make them run?
There's nothing apparent from the description as to what has failed. Perhaps if you can update it with more details, it'd be useful.
From a troubleshooting standpoint, when deploying streams or if the launch of Tasks' fails for any reason, they will be logged in the SCDF-server/Skipper-server logs. You'd have to tail the logs of the respective pod to learn more about the failures.
Also, it'd be useful to verify the output of kubectl describe pod/<POD_NAME> to see what's causing the stream/task pods not to start successfully. They're usually listed towards the end of this command-output.
The usual suspects are due to pods' health-check failures and/or the stream/task application docker images aren't resolvable at runtime. You'll see the reasons in the logs, of course.
This was a misconfiguration on my end.
I'm able to run as expected now.

Does spring-cloud-dataflow provide support for scheduling applications defined as tasks?

I have been looking at using projects built using spring-cloud-task within spring-cloud-dataflow. Having looked at the example projects and the documentation, the indication seems to be that tasks are launched manually through the dashboard or the shell. Does spring-cloud-dataflow provide any way of scheduling task definitions so that they can run for example on a cron schedule? I.e. Can you create a spring-cloud-task app which itself has no knowledge of a schedule, but deploy it to the dataflow server and configure the scheduling there?
Among the posts and blogs I have looked at I noticed the following:
https://spring.io/blog/2016/01/27/introducing-spring-cloud-task
Some of the Q&A afterwards hints at this being a possibility, with the reference to triggers, but I think this was discussed before it was released.
Any advice would be greatly appreciated, many thanks.
There are few ways you could launch Tasks in Spring Cloud Data Flow. Following are the available options today.
Launch it using TriggerTask; with this you could either choose to launch it with fixedDelay or via a cron expression - example here.
Launch it via an event in streaming pipeline. Imagine a use-case where you would want to create a "thumbnail" as and when there's a new image (event) in s3-bucket or in a file-system directory; the "thumbnail" operation could be a task in this case - example here.
Lastly, in the upcoming releases, we will port over "scheduler" functionality from Spring XD to Spring Cloud Data Flow.
Yes, Spring Cloud Data Flow does provide a scheduling option. To enable it, you need to add below arguments while starting the server:
--spring.cloud.dataflow.features.schedules-enabled=true

Error creating the GCE VMs or starting Dataflow

I'm getting the following error in the recent jobs I'm trying to submit:
2015-01-07T15:51:56.404Z: (893c24e7fd2fd6de): Workflow failed.
Causes: (893c24e7fd2fd601):
There was a problem creating the GCE VMs or starting Dataflow on the VMs so no data was processed. Possible causes:
1. A failure in user code on in the worker.
2. A failure in the Dataflow code.
Next Steps:
1. Check the GCE serial console for possible errors in the logs.
2. Look for similar issues on http://stackoverflow.com/questions/tagged/google-cloud-dataflow.
There are no other errors.
What does this error mean?
Sorry for the trouble.
The Dataflow starts up VM instances and then launches an agent on those VMs. Those agents then do the heavy lifting of executing your code (e.g. ParDo's, reading and writing) your Data.
The error indicates the job failed because no agents were requesting work. As a result, the service marked the job as a failure because it wasn't making any progress and never would since there weren't any agents to process your data.
So we need to figure out where in the agent startup process things failed.
The first thing to check is whether the VMs actually started. When you run your job do you see any VMs created in your project? It might take a minute or two for the VMs to startup but they should appear shortly after the runner prints out the message "Starting worker pool setup". The VMs should be named something like
<PREFIX-OF-JOB-NAME>-<TIMESTAMP>-<random hexadecimal number>-<instance number>
Only a prefix of the job name is used to ensure we don't exceed GCE name limits.
If the VMs startup the next thing to do is to inspect the worker logs to look for errors indicating problems in launching the agent.
The easiest way to access the logs is using the UI. Go to the Google Cloud Console and then select the Dataflow option in the left hand frame. You should see a list of your jobs. You can click on the job in question. This should show you a graph of your job. On the right side you should see a button "view logs". Please click that. You should then see a UI for navigating the logs and you can look for errors.
The second option is to look for the logs on GCS. The location to look for is:
gs://PATH TO YOUR STAGING DIRECTORY/logs/JOB-ID/VM-ID/LOG-FILE
You might see multiple log files. The one we are most interested in is the one that starts with "start_java_worker". If that log file doesn't exist then the worker didn't make enough progress to actually upload the file; or else there might have been a permission problem uploading the log file.
In that case the best thing to do is to try to ssh into one of the VMs before it gets torn down. You should have about 15 minutes before the job fails and the VMs are deleted.
Once you login to the VM you can find all the logs in
/var/log/dataflow/...
The log we care most about at this point is:
/var/log/dataflow/taskrunner/harness/start_java_worker-SOME ID.log
If there is a problem starting the code that runs on the VM that log should tell us. That log and the other logs should also tell us if there is a permission problem that prevents the code running on the worker from being able to access Dataflow.
Please take a look and let us know if you find anything.
Apart from Jeremy Lewi's great answer, I would like to add that I've seen this error appear when you don't enable the proper Google APIs in the Developers Console, as mentioned here, which leads to a permission issue, like Jeremy said.

Having C# application communicate with Nagios

We are using Nagios to monitor our network with great results. There is now a new requirement we are struggling with:
We want to notify Nagios of an non
fatal but critical application errors. The
application does not stop running but
there is some sort of issue that
needs looking into.
Once the issue has been looked into,
we need some way to "unflag" the
issue in Nagios.
We tried using the syslog, but the biggest problem was once an error was logged, the service was put into an error state with no way to recover. Also, while applications would report a critical error to the syslog, most of the time they don't report an "All clear" error.
I've done this using passive checks: http://nagios.sourceforge.net/docs/3_0/passivechecks.html
Basically, you're application is just going to feed the nagios core some data into its external command file. Nagios will eventually read the data and update the alerts, execute event handlers, etc.
Exactly how you set this up will be unique for your case, but if you need any other help just let me know. :)

running programs without session

I run my programs and want them to go on running although i logged off from the system.
Is there a way to do this without windows services?
Here is what i want:
I remote connect to the server,
I log in to the server,
I start my program.
I log off from the server but my program continues to running...
thanks.
The only solution that I can think of is running your program as a Windows Service .
there is nothing wrong with using a service. You could go to the length of creating a 'server' part of the program that runs as a service and a 'client' gui. But I assume you aren't talking about software you developed, but something else.
The other way would be to use Scheduled Tasks, that would run a program even if user isn't logged in, useful for backup scripts etc.
An alternative would be to write your program, and schedule it to run in the scheduler.
It depends if you want it to run constantly, or not.
I guess you could follow these instructions to configure your program to run as a service. You will set it's "startup type" to manual so that it will not start each time the operating system starts but instead you log in and start the service manually. Then, when you log off, the service continues running.

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