HP Cisco MDS 8/24c Cisco MDS 9000 Family Release Notes for Cisco MDS NX-OS Rel - Page 22

Downgrading Your Cisco MDS SAN-OS Software Image Send documentation comments to [email protected] • New Features in Cisco MDS NX-OS Release 5.0(4b), page 25 General Downgrading Guidelines Use the following guidelines to nondisruptively downgrade your Cisco MDS NX-OS Release 5.0(4b): • Install and configure dual supervisor modules. • Issue the system no acl-adjacency-sharing execute command to disable ACL adjacency usage on Generation 2 and Generation 1 modules. If this command fails, reduce the number of zones, IVR zones, TE ports, or a combination of these in the system and issue the command again. • Disable all features not supported by the downgrade release. Use the show incompatibility system downgrade-image command to determine what you need to disable. • Use the show install all impact downgrade-image command to determine if your downgrade will be nondisruptive. • Be aware that some features impact whether a downgrade is disruptive or nondisruptive: - Fibre Channel Ports: Fibre Channel ports can be nondisruptively downgraded without affecting traffic on the ports. See Table 14 for the nondisruptive downgrade path for all SAN-OS releases. - SSM: Intelligent services traffic on the SSM, such as SANTap, NASB, and FC write acceleration, is disrupted during a downgrade. SSM Fibre Channel traffic is not. - Gigabit Ethernet Ports: Traffic on Gigabit Ethernet ports is disrupted during a downgrade. This includes IPS modules and the Gigabit Ethernet ports on the MPS-14/2 module, the MSM-18/4 module, and the MDS 9222i switch. Those nodes that are members of VSANs traversing an FCIP ISL are impacted, and a fabric reconfiguration occurs. iSCSI initiators connected to the Gigabit Ethernet ports lose connectivity to iSCSI targets while the downgrade is in progress. - IVR: With IVR enabled, you must follow additional steps if you are downgrading from Cisco SAN-OS Release 2.1.(1a), 2.1(1b), or 2.1.(2a). See the "Upgrading with IVR Enabled" section on page 19 for these instructions. - FICON: If you have FICON enabled, the downgrade path is different. See the "FICON Downgrade Paths" section on page 25. Note A downgrade from NX-OS Release 4.2(1b) to SAN-OS Release 3.3(1x) is not supported on MDS switches, when FC-Redirect based applications, such as Data Mobility Manager or Storage Media Encryption, are configured in the fabric if either of the following conditions are satisfied: 1. A target for which FC-Redirect is configured is connected locally and there are Generation 1 modules with ISLs configured in the switch. 2. A host, for which FC-redirect is configured, is connected locally on a Generation 1 module. If these conditions exist, remove the application configuration for these targets and hosts before proceeding with the downgrade. Use Table 14 to determine the nondisruptive downgrade path from Cisco NX-OS Release 4.2(1b). Find the SAN-OS image you want to downgrade to in the To SAN-OS Release column of the table and use the path recommended. Cisco MDS 9000 Family Release Notes for Cisco MDS NX-OS Release 5.0(4b) 22 OL-21012-04