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Cisco ACI - NTP Configuration


Time and tide wait for none.. definitely not for your Application Centric Infrastructure (ACI)!!





NTP configuration should always be at the top of your list of configuration items, after you un-box your appliance. I won't delve into the reasons for doing this (imagine carrying your cell phone with wrong time).





Disclaimer: The NTP configuration for ACI(just like other configuration in ACI), is not a simple affair, as you would see it below:





  1. Login to APIC (obviously)
  2. Under Fabric >> Select Fabric Policies >> Quickstart >> Configure an NTP policy.
  3. Name the policy and click Next








  • Under NTP Servers, click on the "+" icon and select the NTP server.. can be FQDN or an IP address.. Here I am using pool.ntp.org
  • Use "Management EPG" only if the NTP server is outside the fabric. Click OK and then finish. The NTP policy should now be visible under "Pod Policies".












It's not over yet.. There is more work to be done! The ACI policy configuration requires stitching of the policy and the pod-profile, So let's do that.. (Policy usage in a particular profile can be checked from that policy using "Show usage")





Creating POD policy:





  1. Under Fabric >> Fabric Policies >> Pod Policies >> Policy Groups
  2. Click on Actions and create a new pod policy group. Select the aforementioned NTP policy under "Data Time Policy".
  3. Create a new Pod Profile and reference the pod policy group created above, and Submit.








Verification:





"show ntp" from APIC CLI to see if the APIC has synchronized with NTP server


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