Solved

esx san paths

Posted on 2010-11-22
5
348 Views
Last Modified: 2012-05-10
hi
i have two esx servers connected via fibre cable to a san. i have two hbas in each esx , one cabelled to each san controller etc. when i go into the properties of a lun, i see two paths, one is active and has a green diamond beside it and the other just says on. does this mean that one is the live path and the other comes to life is the active one goes down? do they not load balance?
0
Comment
Question by:mikeleahy
  • 2
  • 2
5 Comments
 
LVL 47

Accepted Solution

by:
dlethe earned 125 total points
ID: 34189493
No, they do not.  Load balancing software is an add-on that is typically offered by your storage vendor.  Sure some HBAs have some path failure software, which are somewhat generic, but load balancing is a whole 'nuther can of worms.  Contact your SAN hardware vendor for advice and pricing.
0
 

Author Comment

by:mikeleahy
ID: 34189535
thanks, thats fine. so theoretically if one of the hbas was re-directed to a different san for example, there would be no slowdown in response from the other hba as only one was being used anyway?
0
 
LVL 3

Assisted Solution

by:vnekic
vnekic earned 125 total points
ID: 34189652
well.. let me start by saying you have to know the SAN.  They are different at times.  But, in most cases... they are not very smart.

This means that you CAN have 2 paths active and pointing to the same LUN.  Which is what you want.

Then from the ESX server you control the management.
First.. you will have BOTH your paths set up in Configuration > Storage Adapters of the ESX machine.

Then from configuration > Storage > (SAN) > Properties > MANAGE PATHS

You will control the path selection.

There you will see the GREEN diamond etc.. of what is live

Why most for HA systems will have 2 SAN Switches to the SAN.  Now, if one fails, the other can take over.

Take a look there and of course talk to your hardware vendor as mentioned by our Genius ;)

0
 

Author Comment

by:mikeleahy
ID: 34189880
thanks
0
 
LVL 47

Expert Comment

by:dlethe
ID: 34190152
Also since you have 2 different servers connected to the same device (I assume), then if they are both active, they will gladly walk all over each other and destroy your data whenever one host writes data that was cached.

I.e,  the selected offset currently holds "ABC"

BOth read, both have ABC in cache.

One host changes to "DEF", and writes, and it is still in cache.

Now at this point,  one server says data contains ABC, the other says it contains DEF, because the CACHED data is different.
0

Featured Post

Easy, flexible multimedia distribution & control

Coming soon!  Ideal for large-scale A/V applications, ATEN's VM3200 Modular Matrix Switch is an all-in-one solution that simplifies video wall integration. Easily customize display layouts to see what you want, how you want it in 4k.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This article will show you how to create an ISO CD-ROM/DVD-ROM image (*.iso), and MD5 checksum signature, for use with VMware vSphere Hypervisor 6.5 (ESXi 6.5). It's a good idea to compare checksums, because many installations fail because of a corr…
In this article we will learn how to backup a VMware farm using Nakivo Backup & Replication. In this tutorial we will install the software on a Windows 2012 R2 Server.
This tutorial will walk an individual through the steps necessary to enable the VMware\Hyper-V licensed feature of Backup Exec 2012. In addition, how to add a VMware server and configure a backup job. The first step is to acquire the necessary licen…
This video shows you how to use a vSphere client to connect to your ESX host as the root user. Demonstrates the basic connection of bypassing certification set up. Demonstrates how to access the traditional view to begin managing your virtual mac…

679 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question