Chapter 20. Designing for nondisruptive upgrades  289
20.2.1  Types of shelf controller module firmware NDUs supported
Shelf controller module firmware NDU is supported or not supported as shown in Table 20-5.
Table 20-5   Shelf firmware NDU support
20.2.2  Upgrading the shelf firmware
The following sections describe how to upgrade shelf controller module firmware.
Manual firmware upgrade
A manual shelf firmware upgrade before the Data ONTAP NDU operations is the preferred 
method. Download the most recent firmware from the IBM Support site to the controllerâs 
/etc/shelf_fw directory, then run the storage download shelf command.
Automatic firmware upgrade
For disruptive (non-NDU) Data ONTAP upgrades, shelf firmware is updated automatically on 
reboot while upgrading Data ONTAP. This process occurs if the firmware on the shelf 
controller modules is older than the version that is bundled with the Data ONTAP system files.
Upgrading individual shelf modules
By default, all shelf modules are upgraded.
For LRC, ESH, ESH2, and ESH4 series modules, you can upgrade a single shelf module or 
the shelf modules that are attached to a specific adapter. To do so, use the storage download 
shelf [adapter_number | adapter_number.shelf_number] command. This command 
informs the user if the upgrade disrupts client I/O and offers an option to cancel the operation.
Systems that use only LRC, ESH, ESH2, or ESH4 shelf modules (in any combination) are not 
disrupted during the upgrade process. They are not disrupted regardless of whether the 
upgrade is performed manually or during storage controller reboot.
20.2.3  Upgrading the AT-FCX shelf firmware on live systems
For systems that incorporate AT-FC, AT-FC2, or AT-FCX shelf modules (including mixed 
environments with LRC or ESHx modules), shelf firmware upgrades occur in two steps. All A 
shelf modules are upgraded first, then all B shelf modules.
Shelf module NDU supported?
ESH/ESH2/ESH4 Yes
AT-FC/AT-FC2 No
AT-F CX Yes
a
a. AT-FCX modules incur two 70-second pauses in I/O for all storage (Fibre Channel, SATA) that 
is attached to the system. AT-FCz NDU functions are available with the release of Data ONTAP 
7.3.2 when AT-FCX firmware version 37 or later is used.
N3000 Yes
b
b. IOM (SAS) modules in a N3000 incur two 40-second pauses in I/O if running firmware versions 
before 5.0 for all storage (SAS, Fibre Channel, or SATA) that are attached to the system. For 
firmware version 5.0 and later, the pauses in I/O are greatly reduced, but not completely 
eliminated.
IOM3 (EXN3000) Yes