Monday, March 17, 2014


Had a great question I wanted to share with you all (names omitted to protect the innocent).  The question was “When doing a motherboard swap or FC HBA swap, why do target WWPN’s not change?”

Answer: Basically WWPN’s are hard coded into the initiator ports but the WWPN’s for target ports are calculated based on the WWNN (see here) and retained statically by ONTAP.

To directly answer the question: “As long as the existing root volume is used in the head swap or upgrade, the same port-to-WWPN mapping applies. For example, port 0a on the replacement head has the same WWPN as the original head. If the new head has different adapter ports, the new ports are assigned new WWPNs.” 
Also interesting:

Tuesday, March 11, 2014

NetApp E-Series Introduction

This is going to be a bit rough and free-form, but this a crash course and "what you actually care about" into NetApp E-Series.  Enjoy!
  • SANtricity is the e-series “filerview” or “system manager.”  Install it on your laptop and directly plug into the system.  Alternatively, set it up like OnCommand on a management server and it will monitor your systems and allow you to manage them from there.
  • There is no “ONTAP.”  It’s SANtricity ES Storage Manager in format 10.86.xx and controller firmware in the format 07.86.xx
  • Systems in SANtricity are referred to as “arrays.”  Each array is two controllers, in one chassis.  The chassis SN is the identifying, unique feature.  Controllers also have SN's.
  • ESM (environment service module?) is the IOM for shelves.
  • Disks are laying in trays you have to slide out to access the disks.

In ONTAP there are two kinds of RAID, RAID4 or RAID6.  But there’s only one kind of aggregate.  In e-series, there are 2.  These are the 2 aggregate equivalents in e-series:

Volume Group: disks put together and assigned a RAID level.  8+2 is recommended.  Can lose 2 in RAID 6.  You can set this to RAID5 though.

Dynamic Disk Pool (DDP):  disks put together with RAID spread across the disks.  Can lose 2/RAID group.  Details below:

I highly recommend reading the key terms portion of pages 1, 65, 66.  Cleared a lot of things up for me!