Bug 1569332

Summary:	[DOCS] WARN users against running master services such as etcd on schedulable nodes
Product:	OpenShift Container Platform	Reporter:	Diane Feddema <dfeddema>
Component:	Documentation	Assignee:	Gaurav Nelson <gnelson>
Status:	CLOSED INSUFFICIENT_DATA	QA Contact:	Vikram Goyal <vigoyal>
Severity:	medium	Docs Contact:	Vikram Goyal <vigoyal>
Priority:	unspecified
Version:	3.7.0	CC:	aos-bugs, dfeddema, gnelson, jokerman, mmccomas
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OS:	Linux
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Last Closed:	2018-06-11 00:25:40 UTC	Type:	Bug
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Description Diane Feddema 2018-04-19 04:54:06 UTC

Document URL: 
https://access.redhat.com/documentation/en-us/openshift_container_platform/3.7/pdf/installation_and_configuration/OpenShift_Container_Platform-3.7-Installation_and_Configuration-en-US.pdf

Section Number and Name: 
Advanced Installation 
section: Configuring Schedulability on Masters
https://docs.openshift.com/container-platform/3.7/install_config/install/advanced_install.html#marking-masters-as-unschedulable-nodes

Describe the issue: 
I have a 2 node openshift 3.7 cluster which became unresponsive because I was running etcd on the same node as my (ML) machine learning application.  My ML application starved etcd of memory and cpu caused etcd to become "dead" as returned from 
"systemctl status etcd"

Suggestions for improvement: 
Instead of this warning which is currently in the installation guide:
"You can manually set a master host to schedulable during installation using the openshift_schedulable=true host variable, though this is not recommended in 
production environments:"

State that it is "IMPORTANT* not to run etcd and other master services on the same node as user pods. 



Additional information:

Comment 2 Gaurav Nelson 2018-05-16 03:17:33 UTC

Tracking this in https://github.com/openshift/openshift-docs/pull/9293

Comment 3 Gaurav Nelson 2018-05-16 03:21:36 UTC

Thank you  Diane, Can you please look at the changes in PR https://github.com/openshift/openshift-docs/pull/9293. These changes are for OCP 3.3 till OCP 3.7 as we already removed that note from OCP 3.9 docs.

Comment 7 Gaurav Nelson 2018-06-11 00:25:40 UTC

No response form reporter, closing this now.