Re: Q: NTP peering configuration

From: sabrina pittarel (sabri_esame@yahoo.com)
Date: Sun Sep 03 2006 - 23:25:21 ART


I saw the thread, but I still was unclear if there was any preference on which router configure it.
 I have a topology similar to the example below, I had configured the peering statement with R3 on R2.
 
 I was expecting that if R2 loses the connection with R1 (the server) the peering relationship between R2 and R3 was still going to be up (and they would adjust the time between each other), but that was not the case:
 
 R2: (after the connection with R1 has been lost)
 ----
 
 R2#sh run | i ntp
 ntp logging
 ntp authentication-key 1 md5 096F673A3A2A 7
 ntp authenticate
 ntp trusted-key 1
 ntp clock-period 17179869
 ntp source Loopback0
 ntp peer 150.3.3.3
 ntp server 136.1.27.1 key 1
 
 
 R2#sh ntp associations
 
       address ref clock st when poll reach delay offset disp
  ~150.3.3.3 136.1.17.2 5 6760 64 0 0.0 0.00 16000.
  ~136.1.27.1 127.127.7.1 3 9969 64 0 -0.2 0.36 16000.
  * master (synced), # master (unsynced), + selected, - candidate, ~ configured
 
 If I check the ntp association on 150.3.3.3 (the peer) nothing is there.
 I could see an association established when R2 had a connection to R1.
 
 Sabrina
 
 

----- Original Message ----
From: Angelo De Guzman <a.deguzman@wesolv.ph.fujitsu.com>
To: ccielab@groupstudy.com; sabrina pittarel <sabri_esame@yahoo.com>
Sent: Sunday, September 3, 2006 6:05:00 PM
Subject: Re:Q: NTP peering configuration

Hi Sabrina,
  Petr mentioned something about this on some a previous thread.

"With NTP peers, you need to configure "ntp trusted-keys" , "ntp
authenticate"
on both sides, since both sides sync each other's clocks. Also put a command
"ntp peer x.x.x.x key x" at least on one side to choose key number.

Angelo

sabrina pittarel (9/4/06 7:45 AM):
>
>Assuming the following topology:
>
>
> R1 ----- R2 ----- R3
>
> R1 is the master and
> R2 is configured with "ntp server <R1>"
>
> I want to establish an NTP peering session between R2 and R3, where is the
best place to configure "ntp peer" cmd ? R2? R3? Does it matter?
> What will be the NTP role of the device without the peering statement?
> Would it be a client? A peer?
>
> Sabrina
>
>_______________________________________________________________________
>Subscription information may be found at:
>http://www.groupstudy.com/list/CCIELab.html
>
>***********************
>No virus was detected in the attachment no filename
>
>Your mail has been scanned by InterScan MSS.
>***********-***********
>

***********************
No virus was detected in the attachment no filename

Your mail has been scanned by InterScan MSS.
***********-***********



This archive was generated by hypermail 2.1.4 : Sun Oct 01 2006 - 16:55:39 ART