RE: ntp authentication

This article needs to be updated for 12.4T IOS where the command ntp trusted-key needs to be added to the time source that is being authenticated. An earlier post in this thread correctly pointed that out.

I will be sure to update this resource with that information.

OT: Brian M. is currently recording some self-paced training from his home in Chicago, and Brian Dennis is in Reno helping train some recent hires. As you know, both are not very active on GS anymore after years of frequent post "status".

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of Antonio Soares
Sent: Wednesday, July 14, 2010 6:59 PM
To: 'Oskar'; ccielab_at_groupstudy.com
Subject: RE: ntp authentication

Check this nice article:

http://www.ine.com/resources/ntp-authentication.htm

OT: By the way, where are the Brians ?

Regards,
 
Antonio Soares, CCIE #18473 (R&S/SP)
amsoares_at_netcabo.pt

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of Oskar
Sent: quarta-feira, 14 de Julho de 2010 18:23
To: ccielab_at_groupstudy.com
Subject: ntp authentication

Hello,

I am playing with NTP authentication and it is not working as I axpect. Here is
the configuration:

R1, master ntp server, authentication configured.
    ntp authentication-key 1 md5 0802455D0A16 7
    ntp master 2

R2, ntp client with authentication, but wrong key configured:
    ntp authentication-key 1 md5 13243531 7
    ntp authenticate
    ntp trusted-key 1
    ntp clock-period 17179862
    ntp server 131.1.12.1 key 1

R3, ntp client, NO authentication configured:
    ntp server 131.1.13.1

As a result:
R2 does not get time from R1 which is expected.
But R3 gets time from R1 even if it has no authentiocation configured:
R3#sh ntp status
Clock is synchronized, stratum 3, reference is 131.1.13.1

Why R3 gets time from R1 then ?

Thanks,

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Received on Wed Jul 14 2010 - 18:23:43 ART