Nexus Features and Feature-Sets
Last Updated: [last-modified] (UTC)
The Nexus platform is modular. Each feature has its own processes, independent of other features. To improve stability, these modules are only enabled as they’re needed. After all, a process that’s not running can’t cause a crash. This has an added benefit of decreasing the attack surface. Let’s not forget the resources savings when only loading required modules. How about upgrades? Yep, they get the benefit too. If a module has a fault, Cisco could release a patch that only updates that module. This helps limit the impact of an upgrade.
Features
To use Nexus features, they first have to be enabled. Sometimes, they have to be installed first. See a list of features with the show feature command.
SY3NX01# show feature Feature Name Instance State -------------------- -------- -------- Flexlink 1 disabled amt 1 disabled bfd 1 disabled bfd_app 1 disabled bgp 1 disabled bulkstat 1 disabled cable-management 1 disabled cts 1 disabled dhcp 1 disabled dot1x 1 disabled eigrp 1 disabled eigrp 2 disabled eigrp 3 disabled eigrp 4 disabled eth_port_sec 1 disabled evmed 1 disabled fabric-access 1 disabled fcoe 1 disabled fcoe-npv 1 disabled fex 1 enabled glbp 1 disabled hsrp_engine 1 enabled http-server 1 disabled interface-vlan 1 enabled ! ---Output omited for brevity---
To enable features. use the feature command. For example feature eigrp will enable the EIGRP processes. Some features, such as EIGRP may use more than one instance. Although this a single feature, each instance runs as a separate process.
Feature Sets
Besides features, there are also feature-sets. Feature sets are similar, except they represent a collection of processes. To use a feature, install it with the install feature-set command. Then, enable it with the feature-set command.
Switch(config)# install feature-set fabricpath Switch(config)# feature-set fabricpath Switch# show feature-set Feature Set Name ID State -------------------- -------- -------- fabricpath 2 enabled fabric 7 uninstalled virtualization 5 uninstalled
Feature-sets are installed per VDC (on platforms that support VDC’s).
An example of a feature-set is fabricpath. This uses a collection of processes, which is why it is a feature-set. On the N7K, some processes run on the supervisor, and some run on the individual IO modules that use it.
Processes
To see a list of processes on the Nexus, use show process.
SY3NX01# show processes
PID State PC Start_cnt TTY Process
----- ----- -------- ----------- ---- -------------
1 S 41520eb8 1 - init
2 S 0 1 - kthreadd
3 S 0 1 - migration/0
4 S 0 1 - ksoftirqd/0
5 S 0 1 - watchdog/0
6 S 0 1 - migration/1
7 S 0 1 - ksoftirqd/1
8 S 0 1 - watchdog/1
9 S 0 1 - events/0
10 S 0 1 - events/1
11 S 0 1 - khelper
12 S 0 1 - netns
! ---Output omited for brevity---
3431 S 41520eb8 1 - fex
3434 S 41523f92 1 - lldp
3435 S 415c4642 1 - netstack
3471 S 41523f92 1 - radius
3472 S 41520eb8 1 - acllog
3473 S 41523f92 1 - cdp
3475 S 41523f92 1 - cfs
3476 S 415c4642 1 - ecp
3477 S 415c4642 1 - igmp
! ---Output omited for brevity---
- NR - 0 - Flexlink
- NR - 0 - tacacs
- NR - 0 - eigrp
- NR - 0 - isis
- NR - 0 - isis_otv
- NR - 0 - ospfv3
- NR - 0 - rip
- NR - 0 - eigrp
- NR - 0 - isis
- NR - 0 - ospf
- NR - 0 - ospfv3
! ---Output omited for brevity---
References
Cisco – Enabling or Disabling Features
NX-OS and Cisco Nexus Switching: Next-Generation Data Center Architectures – Process Modularity
Cisco – Nexus 7000 FabricPath