Fabric OS Administrator's Guide v7.0.0 (53-1002148-02, June 2011)

Fabric OS Administrator’s Guide 195
53-1002148-02
Firmware download process overview
9
Upgrading and downgrading firmware
Upgrading means installing a newer version of firmware. Downgrading means installing an older
version of firmware.
In most cases, you will be upgrading firmware; that is, installing a newer firmware version than the
one you are currently running. However, some circumstances may require installing an older
version; that is, downgrading the firmware. The procedures in this section assume that you are
upgrading firmware, but they work for downgrading as well, provided the old and new firmware
versions are compatible. Always reference the latest release notes for updates that may exist
regarding downgrades under particular circumstances.
For details on Administrative Domains and the firmware download process, see Chapter 17,
“Managing Administrative Domains” for more information.
For details about testing and restoring firmware, see “Test and restore firmware on enterprise-class
platforms” on page 208.
Password-less download of firmware
You can download firmware without a password using the sshutil command for public key
authentication when SSH is selected. The switch has to be configured to install the private key, and
the you must export the public key to the remote host. Before running the firmwareDownload
command, you must first configure the SSH protocol to permit passwordless logins for outgoing
authentication as described in “Configuring outgoing SSH authentication” on page 121
Considerations for FICON CUP environments
To prevent channel errors during nondisruptive firmware installation, the switch CUP port must be
taken offline from all host systems.
HA sync state
High availability (HA) synchronization occurs when two CPs in an enterprise-class platform are
synchronized. This state provides redundancy and a non-disruptive firmware download. In order for
a firmware download to successfully occur, the two CPs in an enterprise-class platform must be in
sync.
If the CPs have mixed versions when you enter the firmwareDownload command, the CPs may not
be in HA sync. In this case, you need to enter the firmwareDownload –s command first to upgrade
or downgrade the standby CP to the same level as the active CP first, and then upgrade the CPs to
the desired version of firmware.
NOTE
Do not run mixed firmware levels on CPs.
Table 46 shows the sync state of an enterprise-class platform that has different Fabric OS versions
installed on the active and standby CP. Use the table to determine if you need to use the
firmwareDownload -s command.