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NX-OS is a network operating system for the Nexus-series Ethernet switches and MDS-series Fibre Channel storage area network switches made by Cisco Systems. It evolved from the Cisco operating system SAN-OS, originally developed for its MDS switches.[1]

It is based on Wind River Linux and is inter-operable with other Cisco operating systems.[citation needed] The command-line interface of NX-OS is similar to that of Cisco IOS.[2]

Recent NX-OS has both Cisco-style CLI and Bash shell available. On NX-OS 7.0(3)I3, the output from uname with the -a command line argument might look like the text below:

$ uname -a
Linux version 3.4.91-WR5.0.1.13_standard+ (divvenka@sjc-ads-7035) (gcc version 4.6.3 (Wind River Linux Sourcery CodeBench 4.6-60) ) #1 SMP Tue Feb 6 12:43:13 PST 2018

Core featuresEdit

  • System Manager (sysmgr)
  • Persistent Storage Service (PSS)
  • Message & Transaction Services (MTS)

Additional featuresEdit

Switches running NX-OSEdit

  • Nexus B22 (HP, Dell, Fujitsu)
  • Nexus 9000 series
  • Nexus 7700 series
  • Nexus 7000 series
  • Nexus 6000 series
  • Nexus 5000 series
  • Nexus 4000 (for IBM BladeCenter)
  • Nexus 2000 series
  • Nexus 3000
  • Nexus 1000V
  • MDS 9700 FC Directors
  • MDS 9500 FC Directors[3]
  • MDS 9250i FC Switch
  • MDS 9222i FC Switch
  • MDS 9100 FC Switches

Differences between IOS and NX-OSEdit

  • NX-OS does not support the login command to switch users.
  • NX-OS does not distinguish between standard or extended access lists, all lists are named and "extended" in functionality.[4]
  • NX-OS did not support scp server prior to 5.1(1) release.
  • In NX-OS, there is no "write" command to save the configuration like on IOS (one uses the "copy" command, instead). Instead, command aliases can be created to provide the "write" command.
  • When accessing NX-OS, users authenticate directly to their assigned privilege level.
  • SSH server is enabled while Telnet server is disabled by default in NX-OS.[5]


4.1, 4.2, 5.0, 5.1, 5.2, 6.0, 6.1, 6.2, 7.0, 9.2

See alsoEdit


  1. ^ "Cisco NX-OS Software: Business-Critical Cross-Platform Data Center OS". Cisco. August 10, 2014. Retrieved June 3, 2017.
  2. ^ Lewis, Mark (April 12, 2008). "Nexus: Hands on with NX-OS, Part#1". Retrieved June 3, 2017.
  3. ^ Cisco Product Brocuhure Cisco MDS 9500 Series of Multilayer Directors, visited 18 May 2012
  4. ^ "Cisco Nexus 7000 Series NX-OS Security Configuration Guide, Release 4.1".
  5. ^ "Cisco NX-OS/IOS Configuration Fundamentals Comparison". Retrieved June 3, 2017.

External linksEdit