Bug 1309414

Summary:	Avoid Running mongodb on NFS server
Product:	Red Hat Satellite	Reporter:	Pradeep Kumar Surisetty <psuriset>
Component:	Docs Install Guide	Assignee:	Stephen Wadeley <swadeley>
Status:	CLOSED CURRENTRELEASE	QA Contact:	Russell Dickenson <rdickens>
Severity:	high	Docs Contact:
Priority:	high
Version:	6.1.6	CC:	adahms, bbuckingham, mhrivnak, mmccune, psuriset, schamilt
Target Milestone:	Unspecified	Keywords:	Triaged
Target Release:	Unused
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2016-09-07 04:19:55 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:

Description Pradeep Kumar Surisetty 2016-02-17 18:07:28 UTC

Description of problem:


Some of the users running mongodb on NFS server and syncing data. It takes huge 
time.  mongodb recommends not to use it on NFS.

Links: 2.4: https://docs.mongodb.org/v2.4/administration/production-notes/
       2.6:  https://docs.mongodb.org/v2.6/administration/production-notes/

MongoDB does not use conventional I/O to access the data files: it uses mmap(). mmap has got issues with nfs. 

Updating documentation would help users to use mongodb on NFS. 

Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
1. Use Mongodb on NFS and run content sync
2.
3.

Actual results:


Expected results:


Additional info:

Comment 1 Bryan Kearney 2016-07-26 19:04:41 UTC

Moving 6.2 bugs out to sat-backlog.

Comment 6 Andrew Dahms 2016-08-23 03:01:28 UTC

Assigning to Stephen for review.

Stephen - I'm not sure if we have a natural place to add this content at the moment, but perhaps it would be a good consideration for the Architecture Guide.

What do you think?

Comment 7 Stephen Wadeley 2016-08-23 07:44:02 UTC

Hello

Re. the Installation Guide

I think we should add this info at the end of the second para in "Storage Recommendations" [1]

in the table just above that, for the /var/lib/mongodb entry, it says  "For improved performance, use solid state drives (SSD) rather than hard disk drives (HDD)." This bug suggests the warning not to use NFS is more important than that comment about drive technology, so we should add this info in brief to that entry. We should then move that line about SSD vs. HDD to the paragraph below in "Storage Recommendations" to avoid table entry bloat.

Re. the Architecture Guide

I searched through this guide and storage and file systems are not discussed. The only time MongoDB is mentioned is in the appendix about technical users.


[1] https://access.redhat.com/documentation/en/red-hat-satellite/6.2/paged/installation-guide/chapter-2-preparing-your-environment-for-installation#idm140560292399744