HP Cisco MDS 8/24c Cisco MDS 9000 Family Release Notes for Cisco MDS NX-OS Rel - Page 21

Downgrading Your Cisco MDS SAN-OS Software Image Send documentation comments to [email protected] If you are upgrading from Cisco MDS SAN-OS Release 3.1(1) to Cisco NX-OS Release 4.2(1b) before upgrading to NX-OS Release 5.0(4b) on a Cisco MDS 9124 or MDS 9134 Switch, follow these guidelines: • During the upgrade, configuration is not allowed and the fabric is expected to be stable. • The Fabric Shortest Path First (FSPF) timers must be configured to the default value of 20 seconds; otherwise, the nondisruptive upgrade is blocked to ensure that the maximum down time for the control plane can be 80 seconds. • If there are any CFS commits in the fabric, the nondisruptive upgrade will fail. • If there is a zone server merge in progress in the fabric, the nondisruptive upgrade will fail. • If a service terminates the nondisruptive upgrade, the show install all failure-reason command can display the reason that the nondisruptive upgrade cannot proceed. • If there is not enough memory in the system to load the new images, the upgrade will be made disruptive due to insufficient resources and the user will be notified in the compatibility table. Performing a Disruptive Upgrade on an MDS 9000 Family Switch If you do not follow the upgrade path when performing a disruptive upgrade on an MDS 9000 Family switch, (for example, you upgrade directly from SAN-OS Release 2.1(2) or earlier version to NX-OS Release 4.2(x)), the binary startup configuration is deleted because it is not compatible with the new image, and the ASCII startup configuration file is applied when the switch comes up with the new upgraded image. When the ASCII startup configuration file is applied, there may be errors. Because of this, we recommend that you follow the nondisruptive upgrade path. Note You cannot upgrade the software image on an MDS 9120 switch, an MDS 9140 switch, or an MDS 9216i switch to Cisco NX-OS Release 5.x. See Table 3 for the list of switches that support Cisco NX-OS Release 5.0(4b). Resetting SNMP Notifications Following a software upgrade or downgrade, SNMP notifications will reset as follows: • When you upgrade from SAN-OS Release 3.x to NX-OS Release 4.1(x), and then to NX-OS Release 5.x, SNMP notifications will reset to their default settings. • When you upgrade from SAN-OS Release 3.x to NX-OS Release 4.2(x), and then to NX-OS Release 5.x, SNMP notifications will not reset to their default settings. • When you downgrade from any NX-OS Release 4.2(x), SNMP notifications will reset to their default configuration settings. Use the snmp-server enable traps command to reenable your required SNMP notifications. Downgrading Your Cisco MDS SAN-OS Software Image This section lists the guidelines recommended for downgrading your Cisco MDS SAN-OS software image and includes the following topics: • General Downgrading Guidelines, page 22 OL-21012-04 Cisco MDS 9000 Family Release Notes for Cisco MDS NX-OS Release 5.0(4b) 21