Chapter 20. Designing For Nondisruptive Upgrades - IBM N Series Hardware Manual

Designing for nondisruptive
Chapter 20.
upgrades
Non Disruptive Upgrade (NDU) began as the process of upgrading Data ONTAP software on
the two nodes in an HA pair controller configuration without interrupting I/O to connected
client systems. NDU has grown since its inception, and now incorporates the nondisruptive
upgrade of system firmware as well.
This chapter covers NDU for the following areas:
System operating software (Data ONTAP) and firmware (BIOS)
Shelf firmware
Disk firmware
Alternate Control Path (ACP) firmware
The overall objective is to enable upgrade and maintenance of the storage system without
affecting the system's ability to respond to foreground I/O requests. This does not mean that
there is no interruption to client I/O. Rather, the I/O interruptions are brief enough so that
applications continue to operate without the need for downtime, maintenance, or user
notification.
Note: Upgrade the system software or firmware in the following order:
1. System firmware
2. Shelf firmware
3. Disk firmware
This chapter includes the following sections:
System NDU
Shelf firmware NDU
Disk firmware NDU
ACP firmware NDU
RLM firmware NDU
© Copyright IBM Corp. 2012. All rights reserved.
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