How I will verify that Camunda is working fine


#1

Hello Team,

We faced so many DB related issues(we are using Oracle DB) & the issues was related to corrupt data. So we reinitialized the DB. Now how can I verify that the camunda engine is working fine?

Thanks,
Sudhanshu


#2

Hi Sudhanshu,

What does working fine mean in your context? There is no ultimate function that tells you that everything is ok, because there are plenty of reasons why an application like Camunda might not work 100%.

Cheers,
Thorben


#3

HI @thorben,

(there are plenty of reasons)… One such example please.

Am getting below line in log several time… where as camunda engine is showing up.

<Enqueued request belonging to Work Manager wm/camunda-bpm-workmanager, application Camunda Engine is cancelled as the Work Manager is shutdown.>

Could you please suggest above could be one of such reason.

Thanks,
Sudhanshu


#4

Are you using Oracle with a READ COMMITTED isolation level? If you are using any sort of cluster, load balancer, etc. It will break Camunda.

Camunda DOES NOT support any database back end that isn’t 100% READ consistent 100% of the time.


#5

We are using Camunda with a 6 node Cluster on Weblogic . ( camunda engine and all war files are deployed to the cluster which deploys it to the individual nodes )
We use Oracle for the database ( which supports READ COMMITTED ).

Is that a problem ?


#6

We are looking for a way to check whether Camunda has started running.
Like a Status web page.
( or a particular line in the log )

On Weblogic, does Camunda becomes fully operational when Weblogic status of the Camunda engine reads RUNNING ?


#7

We are using WildFly, but I don’t think there’s an appreciable difference in this context. One easy way to determine if Camunda is working is to write a simple process and run it. If the process can print (e.g. System.out.println(“I’m working”) in a Groovy script listener) to a server log, then you would see evidence there of Camunda “working”. In your case with a cluster, this might be more difficult unless you can consolidate server logs.

I’ve built various utility processes that test basic function, external services we’ve written, etc.

The most basic way to tell if Camunda is up is if the REST API responds. For example if you use curl on one of the hosts, you might execute the following and you should get some form of response (assuming at least one process is deployed):

curl http://localhost:8080/engine-rest/engine/default/process-definition

This assumes you don’t have any authentication requirements on the REST API. If you do, then you could use something like this:

curl http://camunda:camupass@localhost:8080/engine-rest/engine/default/process-definition

These and other methods you can find in the REST API documentation could be used to determine if it’s working.

With respect to the database, while Oracle may support READ COMMITTED isolation, are you actually using it? Is your Oracle database a cluster of any sort? The last time I checked, the only supported database cluster architecture was MariaDB Galera cluster, configured for READ COMMITTED isolation. The only advantage of that cluster is some resiliency in the database, but you pay a price for that.