Upgrading The Shelf Firmware; Upgrading The At-Fcx Shelf Firmware On Live Systems - IBM N Series Hardware Manual

a. AT-FCX modules incur two 70-second pauses in I/O for all storage (Fibre Channel, SATA)
attached to the system. AT-FCz NDU functions are available with the release of Data ONTAP
7.3.2 when using AT-FCX firmware version 37 or later.
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) attached to the system. For firmware
version 5.0 and later, the pauses in I/O are greatly reduced but not completely eliminated.

20.2.2 Upgrading the shelf firmware

The following sections address how shelf controller module firmware upgrades can occur.
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 controller's
/etc/shelf_fw directory, then issue 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 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 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 will disrupt 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 incorporating 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, and then all B shelf modules.
Normal approach
The storage download shelf process requires 5 minutes to download the code to all A shelf
modules. During this time, I/O is allowed to occur. When the download completes, all A shelf
modules are rebooted. This process incurs up to a 70-second disruption in I/O for the shelf on
both controller modules (when running a firmware version before version 37). This disruption
affects data access to the shelves regardless of whether multipath is configured.
When the upgrade of the A shelf modules completes, the process repeats for all B modules. It
takes 5 minutes to download the code (nondisruptively), followed by up to a 70-second
disruption in I/O.
The entire operation incurs two separate pauses of up to 70 seconds in I/O to all attached
storage, including Fibre Channel if present in the system. Systems employing multipath HA or
Chapter 20. Designing for nondisruptive upgrades
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