[gpfsug-discuss] NDS in Two Site scenario

Ken Hill kenh at us.ibm.com
Wed Jul 20 22:15:49 BST 2016 

                                  Site1         Site2
                                  Server1 (quorum 1) Server3 (quorum 2)
                                  Server2      Server4




                                  SiteX 
                                  Server5 (quorum 3)




You need to set up another site (or server) that is at least power 
isolated (if not completely infrastructure isolated) from Site1 or Site2. 
You would then set up a quorum node at that site | location. This insures 
you can still access your data even if one of your sites go down.

You can further isolate failure by increasing quorum (odd numbers).

The way quorum works is: The majority of the quorum nodes need to be up to 
survive an outage.
 
- With 3 quorum nodes you can have 1 quorum node failures and continue 
filesystem operations.
- With 5 quorum nodes you can have 2 quorum node failures and continue 
filesystem operations.
- With 7 quorum nodes you can have 3 quorum node failures and continue 
filesystem operations.
- etc

Please see 
http://www.ibm.com/support/knowledgecenter/en/STXKQY_4.2.0/ibmspectrumscale42_content.html?view=kc 
for more information about quorum and tiebreaker disks.

Ken Hill
Technical Sales Specialist | Software Defined Solution Sales
IBM Systems


Phone: 1-540-207-7270
E-mail: kenh at us.ibm.com
                     

2300 Dulles Station Blvd
Herndon, VA 20171-6133
United States






From:   "Mark.Bush at siriuscom.com" <Mark.Bush at siriuscom.com>
To:     gpfsug main discussion list <gpfsug-discuss at spectrumscale.org>
Date:   07/20/2016 04:47 PM
Subject:        [gpfsug-discuss] NDS in Two Site scenario
Sent by:        gpfsug-discuss-bounces at spectrumscale.org



For some reason this concept is a round peg that doesn’t fit the square 
hole inside my brain.  Can someone please explain the best practice to 
setting up two sites same cluster?  I get that I would likely have two NDS 
nodes in site 1 and two NDS nodes in site two.  What I don’t understand 
are the failure scenarios and what would happen if I lose one or worse a 
whole site goes down.  Do I solve this by having scale replication set to 
2 for all my files?  I mean a single site I think I get it’s when there 
are two datacenters and I don’t want two clusters typically.
 
 
 
Mark R. Bush | Solutions Architect
Mobile: 210.237.8415 | mark.bush at siriuscom.com
Sirius Computer Solutions | www.siriuscom.com
10100 Reunion Place, Suite 500, San Antonio, TX 78216 
 
This message (including any attachments) is intended only for the use of 
the individual or entity to which it is addressed and may contain 
information that is non-public, proprietary, privileged, confidential, and 
exempt from disclosure under applicable law. If you are not the intended 
recipient, you are hereby notified that any use, dissemination, 
distribution, or copying of this communication is strictly prohibited. 
This message may be viewed by parties at Sirius Computer Solutions other 
than those named in the message header. This message does not contain an 
official representation of Sirius Computer Solutions. If you have received 
this communication in error, notify Sirius Computer Solutions immediately 
and (i) destroy this message if a facsimile or (ii) delete this message 
immediately if this is an electronic communication. Thank you. 
Sirius Computer Solutions _______________________________________________
gpfsug-discuss mailing list
gpfsug-discuss at spectrumscale.org
http://gpfsug.org/mailman/listinfo/gpfsug-discuss




-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://gpfsug.org/pipermail/gpfsug-discuss_gpfsug.org/attachments/20160720/dc6d32f4/attachment-0002.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/png
Size: 1620 bytes
Desc: not available
URL: <http://gpfsug.org/pipermail/gpfsug-discuss_gpfsug.org/attachments/20160720/dc6d32f4/attachment-0022.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/png
Size: 1596 bytes
Desc: not available
URL: <http://gpfsug.org/pipermail/gpfsug-discuss_gpfsug.org/attachments/20160720/dc6d32f4/attachment-0023.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/png
Size: 1071 bytes
Desc: not available
URL: <http://gpfsug.org/pipermail/gpfsug-discuss_gpfsug.org/attachments/20160720/dc6d32f4/attachment-0024.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/png
Size: 978 bytes
Desc: not available
URL: <http://gpfsug.org/pipermail/gpfsug-discuss_gpfsug.org/attachments/20160720/dc6d32f4/attachment-0025.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/png
Size: 1563 bytes
Desc: not available
URL: <http://gpfsug.org/pipermail/gpfsug-discuss_gpfsug.org/attachments/20160720/dc6d32f4/attachment-0026.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/png
Size: 1312 bytes
Desc: not available
URL: <http://gpfsug.org/pipermail/gpfsug-discuss_gpfsug.org/attachments/20160720/dc6d32f4/attachment-0027.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/png
Size: 1167 bytes
Desc: not available
URL: <http://gpfsug.org/pipermail/gpfsug-discuss_gpfsug.org/attachments/20160720/dc6d32f4/attachment-0028.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/png
Size: 1425 bytes
Desc: not available
URL: <http://gpfsug.org/pipermail/gpfsug-discuss_gpfsug.org/attachments/20160720/dc6d32f4/attachment-0029.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/png
Size: 1368 bytes
Desc: not available
URL: <http://gpfsug.org/pipermail/gpfsug-discuss_gpfsug.org/attachments/20160720/dc6d32f4/attachment-0030.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/png
Size: 1243 bytes
Desc: not available
URL: <http://gpfsug.org/pipermail/gpfsug-discuss_gpfsug.org/attachments/20160720/dc6d32f4/attachment-0031.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/png
Size: 4453 bytes
Desc: not available
URL: <http://gpfsug.org/pipermail/gpfsug-discuss_gpfsug.org/attachments/20160720/dc6d32f4/attachment-0032.png>

More information about the gpfsug-discuss mailing list