Hot Add new DS4243 shelf on non HA FAS3140

[JLundfelt]

I need to add a new  DS4243 shelf on non HA FAS3140. Does this cabling look right?

I want to start a new stack, since the only other DS4243 shelf is 7200rpm SAS disk, and this is 15k disk, which I understood was advisable, even though either way it would be a new aggregate-

Thanks,

Jon

[YEKYAWTHARMYINT]

Hi Jon,

You should use square symbol port at TOP Module and circle port at Below Module. You can refer to the below diagram for NetApp SAS cabling guide.

Regards,

Ye

Message was edited by: Ye Kyaw Thar Myint

[JLundfelt]

So if I already have a single DS4243 shelf and a 4port SAS adapter, but its 720rpm disk, should I hot add this new shelf to the existing stack-

or start a new stack? or it it just a personal preference? (I was tol that you shouldn't mix disk shelfs w/ different disk speeds, even if they're going to be allocated to different aggregates.

Thanks,

Jon

[YEKYAWTHARMYINT]

Hi Jon,

You have to start a new stack. Mix with of 7200 and 15k is not the recommended setting. You can use any two empty SAS ports to start new statck for your 7200rpm shelf. first port connect to the IOM A (Top) Square port and second port connect to the IOM B (Below) Square port. In fact, you have only one new shelf so both cable go to the same shelf. Hope it will help.

Regards,

Ye

[shane_bradley]

There’s no problem mixing disk speeds inside a stack. it use to be a problem with FC-AL which was loop based, not so much with SAS. So it comes down really to personal preference.

From the Storage subsystem tech FAQ

https://fieldportal.netapp.com/Core/DownloadDoc.aspx?documentID=75058&contentID=81763

HOW MANY CROSSOVER POINTS BETWEEN SATA AND SAS CAN I IMPLEMENT IN MY DS4243

STACK?

The term “crossover point” refers to the number of times a DS4243 storage shelf makes the transition from

SATA to SAS (or vice versa) within a single stack. Multiple crossover points per stack are supported.

NetApp recommends minimizing the number of crossover points when initially deploying a storage

configuration. As storage configurations grow, it is likely that additional crossover points will be introduced

into the storage configuration. This is acceptable; however, by reducing the number of crossover points in

your stacks, you reduce the variability of the storage configuration. As is true in all computer systems today,

increased variability can add difficulty when troubleshooting issues and also raises the possibility of

encountering unknown issues.

[JLundfelt]

OK, so if I went that route, a hot add would look like-

• Rack shelf, and supply power
• Determine, and set shelf ID
• Power Cycle shelf and confirm shelf ID
• Unplug last shelf SAS connection (RED)
• Plug in Daisy-Chain SAS Ports (GREEN)
• Plug in last shelf SAS connection (RED) - Circled
• Assign Disks
• Create aggregate

BEFORE

AFTER

Thanks!

[shane_bradley]

Yes, that looks fine.

If you can, personally I’d add it as a second stack. it makes sense from a management perspective if you're planning on adding more in the future.

There's no real technical requirement to, its just a personal preference