Initializing Nexus 5K For Storage - (Storage Series Part-2)

As I continue my journey with storage networking, I compiled some more notes today covering Nexus 5K initialization from Fiber Channel Implementation Perspective. Hope you guys will enjoy !!!

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 * To verify SAN Port type and topology on N5k => sh int brief

+ In output look under " Oper Mode "

Sample SAN Port Channel Config
==============================

interface san-port-channel 1
 channel mode active
 switchport mode E
 swithcport trunk allowed vsan 1
 switchport trunk allowed vsan add 10
 switchport speed 4000


* Changing Port Type to FC in 5k
================================

slot 1 or 2
 port 25 - 32 type fc

+ Requires Reload

# " feature fcoe " needs to be turned on separately in order to enable basic FC protocol
     which also further enables actual FCOE. Though NPV for FCOE requires separate license.

+ If port type has been changed to FC but feature fcoe is not enabled, the FC ports 
    will not show up in "sh int brief" output. Also we will not be able to go into FC interface 
    configuration mode.

+ The SFP for storage connecivity is different from SFP for Ethernet connection from 5K standpoint

* FC Auto Negotiation
=====================

> FC Auto Negotiation is enabled by default

> Auto Negotiation Determines:

+ Port Type [ switchport mode ]

+ Trunk Mode [ switchport trunk mode ]

+ Speed [ switchport speed <1000> ]

- From real world standpoint, Port Types etc should be configured manually

* MDS Auto-Negotiation
======================

- MDS port types are by default FX which means it can figure out if it needs to be F or FL 
    port mode during auto-negotiation

- MDS usually can't negotiate E ports so ISL must always be configured manually.

- In MDS E port requires dedicated rate-mode [switchport rate-mode dedicated ]

+ In FC network it's not only SFP type that will control the link speed but also Optical 
    cable should be of same speed in order to match it

+ In FC network there is something known as B2B or Buffer To Buffer credit which is
   analogous to Flow Control is Ethernet Networks.B2B works per link basis and on end 
   to end basis between initiator & target


* FC Trunk Protocol
===================

- Trunk protocol (TP) in FC is analogous to DTP in ethernet and is enabled by default

- Verification - sh trunk protocol

- To disable TP - switchport trunk mode on (Default - auto)

But keep in mind there is no command called "switchport mode te" to statically configure TE port