NX-OS. Nexus Operating System. This operating system has a rich pedigree with its forefathers being heavily embedded in the storage world. SAN-OS originated from the Cisco MDS offerings which has been around since early last decade! Being thrust into the data-centre my exposure to Nexus equipment has sky-rocketed including NX-OS.
Modularity plays a crucial role in NX-OS ability to achieve such fantastic up times. Features themselves can be enabled and disabled as required. This benefit can be seen as a positive in numerous ways. By having features run as separate processes this allows a reduction of memory and CPU process. Don’t need OSPF? Don’t enable. Want vPC but not VTP? Well adjust accordingly. The other great bonus to this is that if OSPF gets AIDS from a neighbour adjacency you don’t lose the box. Simply restart the modular process and major outage avoided.
There are some things to note regarding enabling features and ensuring them to be functional. Turning something on! I know from my IOS experience everything is on by default and it is just the matter of configuring the feature.
N5K-LAB-01(config)# feature ? adapter-fex Enable/Disable adapter-fex feature bgp Enable/Disable Border Gateway Protocol (BGP) dhcp Enable/Disable DHCP Snooping eigrp Enable/Disable Enhanced Interior Gateway Routing Protocol (EIGRP) fcoe Enable/Disable FCoE/FC feature fcoe-npv Enable/Disable FCoE NPV feature fex Enable/Disable FEX flexlink Enable/Disable Flexlink hsrp Enable/Disable Hot Standby Router Protocol (HSRP) interface-vlan Enable/Disable interface vlan lacp Enable/Disable LACP msdp Enable/Disable Multicast Source Discovery Protocol (MSDP) ospf Enable/Disable Open Shortest Path First Protocol (OSPF) pim Enable/Disable Protocol Independent Multicast (PIM) poe Enable/Disable PoE private-vlan Enable/Disable private-vlan privilege Enable/Disable IOS type privilege level support rip Enable/Disable Routing Information Protocol (RIP) ssh Enable/Disable ssh tacacs+ Enable/Disable tacacs+ telnet Enable/Disable telnet udld Enable/Disable UDLD vpc Enable/Disable VPC (Virtual Port Channel) vrrp Enable/Disable Virtual Router Redundancy Protocol (VRRP) vtp Enable/Disable Vlan Trunking Protocol (VTP)
Look at that. Simple. Just remember to check that a feature is on before configuring it and panicking that you’ve got the wrong licence!
N5K-LAB-01(config)# feature vpc
Feature running! Presto! Now remember you can use show feature to gain a quick overview of what is enabled and what is disabled.
THO-EST-SVRSW-P1-1# sh featFeature Name Instance State-------------------- -------- --------Flexlink 1 disabledadapter-fex 1 disabledbgp 1 disableddhcp 1 disabledeigrp 1 disabledeigrp 2 disabledeigrp 3 disabledeigrp 4 disabledfcoe 1 disabledfcoe-npv 1 disabledfex 1 enabledhsrp_engine 1 disabledinterface-vlan 1 enabledlacp 1 enabledldap 1 disabledlldp 1 enabledmsdp 1 disabledospf 1 disabledospf 2 disabledospf 3 disabledospf 4 disabledpim 1 disabledpoe 1 disabledprivate-vlan 1 disabledprivilege 1 disabledrip 1 disabledrip 2 disabledrip 3 disabledrip 4 disabledsshServer 1 enabledtacacs 1 enabledtelnetServer 1 enabledudld 1 enabledvem 1 disabledvpc 1 enabledvrrp 1 disabledvtp 1 enabled
I really have taken to the concept of this modularity. I hope it works as long as it isn’t licensed to stupidity like the ASA has become. My only gripe thus far – Y U NO SAFE HARBOUR?!