HP A7533A - Brocade 4Gb SAN Switch Base Release Note page 21

To ensure nondisruptive Hot Code Load (HCL), neighbor switches should be operating with Fabric
OS 6.2.0a or later before loading Fabric OS 6.2.1 on the following platforms:
Brocade 4Gb SAN Switch for HP p-Class BladeSystem
Brocade 4Gb SAN Switch for HP c-Class BladeSystem
HP StorageWorks SAN Switch 4/32
HP StorageWorks 4/8 and 4/16 SAN Switches
When upgrading to Fabric OS 6.2.1 from Fabric OS 6.1.0g or earlier, the CPs do not fully synchronize
until both the new active and new standby CPs are running Fabric OS 6.2.1. This is normal behavior
and the firmware upgrade is not disruptive.
Fabric OS 6.2.1 does not support concurrent FC Routing (EX_Ports) and Top Talkers features Upgrading
to Fabric OS 6.2.1 requires that one of these features be disabled first.
Only products based on 4–Gb and 8–Gb-capable ASICs are supported by Fabric OS 6.2.1. Older
products using previous generation 2–Gb ASICs will remain on the 5.x code stream. Fabric OS 5.x
is fully compatible in fabrics running Fabric OS 6.2.x and for routing.
For routed SANs with M-EOS switches in an edge fabric, upgrades to Fabric OS 6.2.1 are
nondisruptive if all EX_Ports to M-EOS edge fabrics are attached to 4/256 SAN Directors with an
MP router blade (FR4-18i).
The HP StorageWorks DC SAN Director with HP StorageWorks DC Switch Encryption FC Blade and
the HP StorageWorks Encryption SAN Switch cannot be downgraded to a version earlier than Fabric
OS 6.2.0b.
After upgrading the Encryption SAN Switch and the DC SAN Director with DC Switch Encryption FC
Blade to Fabric OS 6.2.1, you cannot downgrade them to a version earlier than Fabric OS 6.2.1 if
HP SKM key vault is configured. Doing so will result in the loss of encryption services in HP SKM
environments.
If there are multiple node encryption groups (EGs) in a fabric, complete the firmware download on
one node at a time before downloading on another node.
On the HP StorageWorks 8/8 and 8/24 SAN Switches and the Brocade 8Gb SAN Switch for HP
BladeSystem c-Class, do not use the -n option to downgrade from Fabric OS 6.2.1 to an earlier
version. If you use the -n option, the firmware versions may get out of sync, which can cause rolling
kernel panics. The switch will not be recoverable and you will need to return it to your supplier for
repair via RMA.
Firmware upgrade instructions
IMPORTANT:
HP recommends that users upgrade to Fabric OS 6.2.1 as soon as possible. Upgrading to Fabric OS
6.2.1 is allowed only from Fabric OS 6.1.x. See
guidelines.
Update recommendations" on page 8 for additional
HP StorageWorks Fabric OS 6.2.1 release notes 21