Setting up NTP to synchronize time stamps for syslogs

R871#sh clock
*20:16:19.958 UTC Tue Mar 5 2002
R871#clock set ?
hh:mm:ss Current Time

R871#clock set 17:55:00 ?
<1-31> Day of the month
MONTH Month of the year

R871#clock set 17:55:00 1 ?
MONTH Month of the year

R871#clock set 17:55:00 1 april ?
<1993-2035> Year

R871#clock set 17:55:00 1 april 2010 ?
<cr>

R871#clock set 17:55:00 1 april 2010
R871#
*Apr 1 17:55:00.000: %SYS-6-CLOCKUPDATE: System clock has been updated from 20:17:02 UTC Tue Mar 5 2002 to 17:55:00 UTC Thu Apr 1 2010, configured from console by console.
R871#

Set R871 as the master NTP server:
R871(config)#ntp master ?
<1-15> Stratum number
<cr>
R871(config)#ntp master 3

Stratum number is the distance from the source.

Reverse telnet to 2950-1
I cannot remember my router’s ip address, i can use cdp to help me get the information.

2950-1(config)#do sh cdp nei deta
————————-
Device ID: R871.cyruslab.com
Entry address(es):
IP address: 10.10.10.1
Platform: Cisco 871, Capabilities: Router Switch IGMP
Interface: FastEthernet0/1, Port ID (outgoing port): FastEthernet3
Holdtime : 178 sec

Version :
Cisco IOS Software, C870 Software (C870-ADVIPSERVICESK9-M), Version 12.4(15)T7, RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2008 by Cisco Systems, Inc.
Compiled Thu 14-Aug-08 07:43 by prod_rel_team

advertisement version: 2
VTP Management Domain: ‘cyrus’
Native VLAN: 100
Duplex: full
Management address(es):

Set ntp server ip address.
2950-1(config)#ntp server 10.10.10.1

Verify:
2950-1(config)#do sh clock
18:03:26.821 UTC Thu Apr 1 2010

Verify that my 2950 switch has association with the router
2950-1#sh ntp associations

address ref clock st when poll reach delay offset disp
*~10.10.10.1 127.127.7.1 3 50 64 377 2.7 22.03 17.8
* master (synced), # master (unsynced), + selected, – candidate, ~ configured

Verify 2950 association with 871 in detail:

2950-1#sh ntp associations detail
10.10.10.1 configured, our_master, sane, valid, stratum 3
ref ID 127.127.7.1, time CF5F5EA3.40855488 (18:04:19.252 UTC Thu Apr 1 2010)
our mode client, peer mode server, our poll intvl 64, peer poll intvl 64
root delay 0.00 msec, root disp 0.03, reach 377, sync dist 28.397
delay 2.72 msec, offset 40.3455 msec, dispersion 27.01
precision 2**18, version 3
org time CF5F5ECE.2EF54D04 (18:05:02.183 UTC Thu Apr 1 2010)
rcv time CF5F5ECE.24FAAAA1 (18:05:02.144 UTC Thu Apr 1 2010)
xmt time CF5F5ECE.2446B791 (18:05:02.141 UTC Thu Apr 1 2010)
filtdelay = 2.72 2.72 2.73 2.69 2.72 2.81 3.65 2.73
filtoffset = 40.35 22.03 4.38 4.12 3.81 3.52 2.84 2.94
filterror = 0.02 0.99 1.97 1.98 2.00 2.01 2.03 2.04

Go to 2950-2:
Tserver#2950-2
Trying 2950-2 (1.1.1.1, 2002)… Open

2950-2#

I felt having vlan1 with an ip address is really easy…. no wonder it is known for management vlan.

Device ID: R871.cyruslab.com
Entry address(es):
IP address: 10.10.10.1
Platform: Cisco 871, Capabilities: Router Switch IGMP
Interface: FastEthernet0/1, Port ID (outgoing port): FastEthernet2
Holdtime : 128 sec

Version :
Cisco IOS Software, C870 Software (C870-ADVIPSERVICESK9-M), Version 12.4(15)T7, RELEAS E SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2008 by Cisco Systems, Inc.
Compiled Thu 14-Aug-08 07:43 by prod_rel_team

advertisement version: 2
VTP Management Domain: ‘cyrus’
Native VLAN: 100
Duplex: full
Management address(es):

2950-2#conf t
Enter configuration commands, one per line. End with CNTL/Z.
2950-2(config)#ntp server 10.10.10.1
2950-2(config)#

Verify:
2950-2(config)#do sh clock
18:09:01.248 UTC Thu Apr 1 2010

Verify association with 871:
2950-2(config)#do sh ntp assoc

address ref clock st when poll reach delay offset disp
*~10.10.10.1 127.127.7.1 3 43 64 377 2.7 4.02 0.5
* master (synced), # master (unsynced), + selected, – candidate, ~ configured
2950-2(config)#

Verify in detail:
2950-2(config)#do sh ntp assoc detail
10.10.10.1 configured, our_master, sane, valid, stratum 3
ref ID 127.127.7.1, time CF5F5FA3.40843D4F (18:08:35.252 UTC Thu Apr 1 2010)
our mode client, peer mode server, our poll intvl 64, peer poll intvl 64
root delay 0.00 msec, root disp 0.03, reach 377, sync dist 1.877
delay 2.70 msec, offset 4.0154 msec, dispersion 0.50
precision 2**18, version 3
org time CF5F5FA6.3BCC8749 (18:08:38.233 UTC Thu Apr 1 2010)
rcv time CF5F5FA6.3B0CE0B3 (18:08:38.230 UTC Thu Apr 1 2010)
xmt time CF5F5FA6.3A578EFF (18:08:38.227 UTC Thu Apr 1 2010)
filtdelay = 2.75 2.70 2.75 2.72 2.72 2.81 11.72 2.72
filtoffset = 4.30 4.02 3.68 3.40 3.10 2.80 -1.67 2.19
filterror = 0.02 0.03 0.05 0.06 0.08 0.09 0.11 0.12