HP Cisco Nexus 5000 Cisco MDS 9000 Family Release Notes for Cisco MDS NX-OS Re - Page 27

Downgrading Your Cisco MDS SAN-OS Software Image Send documentation comments to [email protected] Downgrading the SSI Image on Your SSM Use the following guidelines when downgrading your SSI image on your SSM: • On a system with at least one SSM installed, the install all command might fail on an SSM when you downgrade from Cisco NX-OS Release 4.1(x) to any SAN-OS 2.x release earlier than SAN-OS Release 2.1(2e). Power down the SSM and perform the downgrade. Bring up the SSM with the new bootvar set to the 2.x SSI image. • Downgrade the SSI boot images on the SSMs on the switch to a release version supported by your Cisco SAN-OS release. Refer to the Cisco MDS SAN-OS Release Compatibility Matrix for Storage Service Interface Images. • SSM intelligent services traffic switching on SSM ports is disrupted on upgrades or downgrades. • Fibre Channel switching traffic on SSM ports is not disrupted under the following conditions: - All SSM applications are disabled. Use the show ssm provisioning command to determine if any applications are provisioned on the SSM. Use the no ssm enable feature configuration mode command to disable these features. - The EPLD version on the SSM is at 0x07 or higher. Use the show version module slot epld command to determine your EPLD version. Refer to the Cisco MDS 9000 Family Release Notes for Cisco MDS 9000 EPLD Images to upgrade your EPLD image. - Refer to the Cisco Data Center Interoperability Support Matrix and the "Managing Modules" chapter in the Cisco MDS 9000 Family CLI Configuration Guide, Release 3.x, for information on downgrading your SSM. Downgrading an MDS 9500 Series Switch with an 8-Gbps Module Installed If you attempt to perform a nondisruptive software downgrade from NX-OS Release 4.x to SAN-OS Release 3.x on an MDS 9500 Series switch that has an 8-Gbps module installed, the switch should display a message that the module is unsupported and stop the downgrade. Instead, the switch displays a message that the module is unsupported and proceeds with a disruptive downgrade. The following table shows the actual and expected behavior of the switch for a software downgrade. Table 13 Downgrade Behavior on an MDS 9500 Series Switch with 8-Gbps Module Installed Crossbar Fabric Mode DB mode1 Switch Type MDS 9513 with 8-Gbps module Software Version 4.2(1a) Downgrade Software Version 3.3(x) Actual Install Behavior Disruptive DB mode BM mode2 MDS 9513 without 4.2(1a) 8-Gbps module MDS 9513 with 8-Gbps module 4.2(1a) 3.3(x) 3.3(x) Disruptive Abort BM mode MDS 9513 without 4.2(1a) 8-Gbps module 3.3(x) Nondisruptive Expected Install Behavior Abort. Disruptive after powerdown of 8-Gbps module Disruptive Abort. Nondisruptive after powerdown of 8-Gbps module. Nondisruptive OL-19964-02 Cisco MDS 9000 Family Release Notes for Cisco MDS NX-OS Release 4.2(1a) 27