How does an Oozie coordinator react on an underlying workflow change?

0
votes

I have a question about Apache Oozie and more specifically on the CDH distribution.

What happens to a coordinator when the workflow it uses has been modified? For example the workflow now uses an extra parameter which is automatically filled in by a variable. This would in theory not require any changes on the coordinator. Do running coordinators still use the configuration of the initial workflow or do they dynamically adapt to the new one. If they still use the old configuration do I then need to define a new coordinator or is resubmitting the same coordinator enough?

1
hadoopooziecloudera-cdhoozie-coordinator
I believe workflow.xml has changed for you. Is the new config parameter is already present in the configuration submitted to coord? - YoungHobbit
I am not really sure what you are asking here. No change is needed for the coordinator, but the workflow.xml for the workflow indeed has changed. I am asking how the coordinator is linked to the workflow. Is a running coordinator linked to the previous file, which I would find logical? Second question is a coordinator which is not running linked to the old file or to the new? Meaning: do I need to create a new coordinator, update my coordinator or can I just resubmit? @YoungHobbit - spijs
If just the workflow.xml has changed, then replace the workflow.xml in the HDFS (the application path you have provided into the coordinator). For the next execution it will pick the new workflow. Just make sure the new/changed parameter is already present in the submitted coordinator. Thanks. - YoungHobbit

1 Answers

2
votes

This is how it works: Every submitted coordinator has a fixed set of variables and parameters (config file). The -change option allows you to change the following attributes of the coordinator:

  • endtime: the end time of the coordinator job.
  • concurrency: the concurrency of the coordinator job.
  • pausetime: the pause time of the coordinator job.

Everything with the exception of the Coordinator coordinator name, frequency, start time, end time and timezone can be changed with the -update option. For details see the official documentation:

http://oozie.apache.org/docs/4.3.0/DG_CommandLineTool.html#Updating_coordinator_definition_and_properties

In the config file you are usually pointing to a coordinator file in hdfs which then points to a workflow file in hdfs. If you change either of these in hdfs, the next time the coordinator triggers it will use the new/modified files. The same holds true, for all files that are being used in workflow actions e.g. shell scripts, Jar-files, ...