Cisco Cisco MDS 9000 NX-OS Software Release 4.2 Notas de publicación

Cisco MDS NX-OS Release 4.2(7a) is a maintenance release. It includes bug fixes and the following new 
features:

Slow Drain Device Detection and Congestion Avoidance

The slow drain feature provides various enhancements to detect slow drain devices that cause 
congestion in the network and lead to an ISL credit shortage in the traffic destined for these devices. 
The credit shortage affects the unrelated flows in the fabric that use the same ISL link even though 
destination devices do not experience slow drain. The slow drain feature also includes a congestion 
avoidance function. 

The slow drain feature is enabled by default. Before you install Cisco NX-OS Release 4.2(7a), 
we recommend that you read the slow drain configuration information that is available in the 
“Configuring Interfaces” section of the 

The slow drain feature is not supported on the following Cisco MDS 9000 components:

Supervisor-1 modules

Generation 1switching modules

Cisco MDS 9216 switch, MDS 9216i switch, MDS 9120 switch, and the MDS 9140 switch

MIB Updates

Objects were added to the FC-FE-MIB.

The following objects were added to FcIfErrorEntry: 

fcIfTimeOutDiscards,

fcIfOutDiscards,

fcIfCreditLoss,

fcIfTxWtAvgBBCreditTransitionToZero

Documentation for MIBs is available in the

Most Cisco MDS 9000 family software features are included in the standard package. However, some 
features are logically grouped into add-on packages that must be licensed separately, such as the Cisco 
MDS 9000 Enterprise package, SAN Extension over IP package, Mainframe package, Fabric Manager 
Server (FMS) package, Storage Services Enabler (SSE) package, Storage Media Encryption package, 
and Data Mobility Manager package. On-demand ports activation licenses are also available for the 
Cisco MDS Blade Switch Series and 4-Gbps Cisco MDS 9100 Series Multilayer Fabric switches.