[time-nuts] Cisco Nexus switches and the leap second

Ryan Stasel rstasel at uoregon.edu
Fri Jun 26 15:40:02 EDT 2015


Thought this might be of interest to the group. It seems Cisco, at this time, is recommending most users turn off NTP some of their higher end (Data center oriented) switches (Nexus series, at least) until after the leap second then re-enable. 

For example: 
http://www.cisco.com/web/about/doing_business/leap-second.html (this is entertaining since it doesn’t actually admit there are any issues)

Here are links to some of the bugs:


I found out about this since our network team on campus is doing just this… turning off NTP until after, then turning it back on. I find it pretty amazing that it actually causes the switch to lock up. 

I guess after things went sideways (a bit) in 2012 they didn’t think it was a big deal to address completely before this year. 

Anyway, just figured it might be of interest to those on this list that are also involved in data Networking (or just find it interesting).

-Ryan Stasel

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