Setting the Clock on a Nexus 5K

Carole Warner Reece

I noticed that you may not initially be able to set the clock time and date on Nexus 5Ks. For example:

SWITCH-5K2# sh clock
18:16:56.460 UTC Fri Jun 12 2009
SWITCH-5K2# clock set 13:21:00 13 feb 2014
Setting clock from CLI is not allowed in this VDC.

However, the clock set command worked fine on my Nexus 7Ks. After a bit of digging, I found that this is a known big in NX-OS 5.2(1) on Nexus 5Ks:

I also noticed that I had an impacted version of the NX-OS:

SWITCH-5K2# sh ver | i system:
  system:    version 5.2(1)N1(1b)

There are a couple of work-arounds:

a) You can set the clock protocol to none in configuration mode, and then set the clock and time.

SWITCH-5K2#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
SWITCH-5K2(config)# clock prot none
SWITCH-5K2(config)# clock set 13:23:00 13 feb 2014
Thu Feb 13 13:23:00 UTC 2014
SWITCH-5K2(config)# sh clock 
13:23:11.122 UTC Thu Feb 13 2014

b) You could also use NTP (or PTP) to set the clock and date.

SWITCH-5K2(config)# clock prot ntp 
SWITCH-5K2(config)# sh cloc 
13:23:31.519 UTC Thu Feb 13 2014 
SWITCH-5K2(config)# sh run | i ntp 
SWITCH-5K2(config)# ntp server use-vrf management 
SWITCH-5K2(config)# ! my NTP server is reachable from the management port 
. . .
! wait awhile for NTP to synch with the server (also for me to eat lunch)
SWITCH-5K2# sh clock 
14:34:43.470 UTC Thu Feb 13 2014 
SWITCH-5K2# sh ntp statistic loc
system uptime:          8017
time since reset:       8017
old version packets:    482
new version packets:    0
unknown version number: 0
bad packet format:      0
packets processed:      482
bad authentication:     0
SWITCH-5K2# sh ntp peer-status
Total peers : 1
* - selected for sync, + -  peer mode(active), 
- - peer mode(passive), = - polled in client mode 
    remote               local                 st   poll   reach delay
*                    2   64     377   0.00189 

— cwr

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Nick Kelly

Cybersecurity Engineer, Cisco

Nick has over 20 years of experience in Security Operations and Security Sales. He is an avid student of cybersecurity and regularly engages with the Infosec community at events like BSides, RVASec, Derbycon and more. The son of an FBI forensics director, Nick holds a B.S. in Criminal Justice and is one of Cisco’s Fire Jumper Elite members. When he’s not working, he writes cyberpunk and punches aliens on his Playstation.


Virgilio “BONG” dela Cruz Jr.

CCDP, CCNA V, CCNP, Cisco IPS Express Security for AM/EE
Field Solutions Architect, Tech Data

Virgilio “Bong” has sixteen years of professional experience in IT industry from academe, technical and customer support, pre-sales, post sales, project management, training and enablement. He has worked in Cisco Technical Assistance Center (TAC) as a member of the WAN and LAN Switching team. Bong now works for Tech Data as the Field Solutions Architect with a focus on Cisco Security and holds a few Cisco certifications including Fire Jumper Elite.


John Cavanaugh

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John is our CTO and the practice lead for a talented team of consultants focused on designing and delivering scalable and secure infrastructure solutions to customers across multiple industry verticals and technologies. Previously he has held several positions including Executive Director/Chief Architect for Global Network Services at JPMorgan Chase. In that capacity, he led a team managing network architecture and services.  Prior to his role at JPMorgan Chase, John was a Distinguished Engineer at Cisco working across a number of verticals including Higher Education, Finance, Retail, Government, and Health Care.

He is an expert in working with groups to identify business needs, and align technology strategies to enable business strategies, building in agility and scalability to allow for future changes. John is experienced in the architecture and design of highly available, secure, network infrastructure and data centers, and has worked on projects worldwide. He has worked in both the business and regulatory environments for the design and deployment of complex IT infrastructures.