Created on
06-24-2020
01:21 PM
- last edited on
06-24-2020
10:55 PM
by
VidyaSargur
Hi, I have implemented a CM Extension following the guide on the wiki. Our service needs to stop and start in a particular order when executing the stop/start cluster action (and rolling restarts, etc.). We want our service to stop after HDFS Datanode and start before HDFS Datanode. We have implemented a similar extension for Ambari, and in Ambari this feature is called Role Command Order. This is our Ambari role command order json:
{
"general_deps": {
"_comment": "dependencies for CUSTOM_SERVICE when starting and stopping all services.",
"CUSTOM_SERVICE-STOP": ["DATANODE-STOP"],
"DATANODE-START": ["CUSTOM_SERVICE-START"]
}
}
Does Cloudera Manager have a similar feature for controlling start and stop order? I could not find anything in the service descriptor language reference.
Thanks.
Created 06-29-2020 07:26 AM
Given the lack of replies I am guessing I am not reaching the people who might know the answer to my question. Can anybody give me guidance how to best reach the CM experts, and particularly someone who knows how CM Extensions and start/stop ordering works? This is quite important for our project. Thanks!
Created 06-29-2020 08:19 AM
Hello @hitachi_ben :
Have you gone through the cloudera documentation links ?? for the version what you have..
I meant the general administration document would give some knowledge and about adding extensions if they have explicitly mentioned you can proceedwith that.
References:
https://docs.cloudera.com/documentation/enterprise/5-3-x/topics/cm_mc_rolling_restart.html
https://docs.cloudera.com/documentation/enterprise/5-3-x/categories/hub_administrators.html
Created 07-08-2020 10:04 AM
Thanks @Govins , but neither of these resources contains any reference to role start/stop ordering. I assume it is possible but the mechanism does not seem to be documented and CM source code is not open. Very frustrating.
Created 02-25-2021 06:52 AM
+1
I am looking for this too. In my case, I have 2 Roles in my custom CM service which are installed on all nodes and I want one role to always start before the other one and stop in the opposite order when the service is started.
Would appreciate any solutions for this. Thanks.