01-03-2023 11:28 AM
Hello
I have questions about the ntp broadcast (server) <--> ntp broadcast client.
In my scenario is:
On router R1 (NTP server on 1841 router) the ntp broadcast is active on Fa8 (trunk port).
On SW1 (Catalyst 2960) the ntp broadcast client is on Fa0/13 (trunk port).
From the switch I can "ping" the router R1
At what intervals is the time broadcast from the server and what accuracy can be expected?
Is there any way to "debug" this kind of time sysnchronization.
I don't see any time correction on the client.
Solved! Go to Solution.
01-04-2023 02:18 AM
Ok. Problem found. not all vlans were enabled on the trunk. Alternative vlan on the server set to broadcasting (VLAN 99), now it runs - stupid error - thanks for your help!
Here are the new logs:
Jan 4 09:48:32.993: NTP recv pkt on v4 socket, pak = 0x029CA8EC.
Jan 4 09:48:33.001: NTP message received from 10.15.99.1 on interface 'Vlan99' (10.15.99.2):
Jan 4 09:48:33.001:
NTP Header:
Leap = 00, Version = 3, Mode = 4,
Stratum = 2,
Poll Interval = 6,
Precision = -18,
Root Delay = 0.850,
Root Dispersion = 0.140,
refid = 192.33.96.102,
Last update reftime = 3881814571.1858855000,
Originated time = 3881814512.4017030050,
Received time = 3881814642.536004346,
Transmit time = 3881814642.536049700.
Hexadecimal equivalent (length = 48):
0000: 1C 02 06 EE 00 00 03 52
0008: 00 00 00 8C C0 21 60 66
0010: E7 5F CA 2B 6E CB E0 58
0018: E7 5F C9 F0 EF 6F 03 A2
0020: E7 5F CA 72 1F F2 C6 FA
0028: E7 5F CA 72 1F F3 78 24
Jan 4 09:48:33.001: NTP Core(DEBUG): ntp_receive: message received
Jan 4 09:48:33.001: NTP Core(DEBUG): ntp_receive: peer is 0x01FBB5A8, next action is 1.
Jan 4 09:48:33.001: NTP Core(DEBUG): receive: packet given to process_packet
Jan 4 09:48:33.001: NTP Core(DEBUG): Peer becomes reachable, poll set to 6.
Jan 4 09:48:33.001: NTP Core(INFO): peer 10.15.99.1 event 'event_reach' (0x84) status 'unreach, 1 event, event_reach' (0x14)
Jan 4 09:48:33.001: NTP Core(INFO): synchronized to 10.15.99.1, stratum 2
Jan 4 09:48:33.001: NTP: step(0x00000081.27F01065): local_offset = 0x00000000.00000000, curtime = 0xE75FC9F1.005ED1F4
Jan 4 09:50:42.157: NTP Core(NOTICE): time reset 129.156006 s
Jan 4 09:50:42.157: NTP Core(DEBUG): bcast client cleared
Jan 4 09:51:41.448: NTP recv pkt on v4 socket, pak = 0x021F9650.
Jan 4 09:51:41.448: NTP message received from 10.15.99.1 on interface 'Vlan99' (255.255.255.255):
Jan 4 09:51:41.448:
01-03-2023 11:32 AM
the NTP broadcast need config in server and client
in server
ntp broadcast
in client
ntp broadcast client
01-03-2023 11:37 AM - edited 01-03-2023 11:38 AM
Thanks for the response.
This is how I configured R1 and SW1, according to instructions from the manuals
01-03-2023 11:42 AM
are the time different is large ? if yes then it need long time to adjust,
workaround is manual adjust the time to be near the value and then check again.
01-03-2023 11:53 AM
At the moment I have set the time manually on the client with about 3 minutes deviation from the server. This remains so and is not adjusted to the server.
01-03-2023 12:03 PM
3 min but which year ? is it same or many year different between both side ?
01-03-2023 12:05 PM
year and date are set correctly on both devices
01-03-2023 12:10 PM - edited 01-03-2023 12:11 PM
01-04-2023 01:17 AM
On SW1 I have the debugging running, this is what I got. The time has not been corrected after 12 h.
sw1#debug ntp all
NTP events debugging is on
NTP core messages debugging is on
NTP clock adjustments debugging is on
NTP reference clocks debugging is on
NTP packets debugging is on
sw1#
Jan 4 08:59:59.939: NTP Core(DEBUG): drift value to save: 0.000000000
Jan 4 08:59:59.939: %NTP : Drift string saved to persistent data: NTPv4_Drift=0.0
Jan 4 08:59:59.939: NTP Core(DEBUG): drift value saved.
Jan 4 08:59:59.939: NTP Core(DEBUG): hourly stats called. Count=15
01-04-2023 02:10 AM
share the
show ntp asso detail
01-04-2023 02:18 AM
Ok. Problem found. not all vlans were enabled on the trunk. Alternative vlan on the server set to broadcasting (VLAN 99), now it runs - stupid error - thanks for your help!
Here are the new logs:
Jan 4 09:48:32.993: NTP recv pkt on v4 socket, pak = 0x029CA8EC.
Jan 4 09:48:33.001: NTP message received from 10.15.99.1 on interface 'Vlan99' (10.15.99.2):
Jan 4 09:48:33.001:
NTP Header:
Leap = 00, Version = 3, Mode = 4,
Stratum = 2,
Poll Interval = 6,
Precision = -18,
Root Delay = 0.850,
Root Dispersion = 0.140,
refid = 192.33.96.102,
Last update reftime = 3881814571.1858855000,
Originated time = 3881814512.4017030050,
Received time = 3881814642.536004346,
Transmit time = 3881814642.536049700.
Hexadecimal equivalent (length = 48):
0000: 1C 02 06 EE 00 00 03 52
0008: 00 00 00 8C C0 21 60 66
0010: E7 5F CA 2B 6E CB E0 58
0018: E7 5F C9 F0 EF 6F 03 A2
0020: E7 5F CA 72 1F F2 C6 FA
0028: E7 5F CA 72 1F F3 78 24
Jan 4 09:48:33.001: NTP Core(DEBUG): ntp_receive: message received
Jan 4 09:48:33.001: NTP Core(DEBUG): ntp_receive: peer is 0x01FBB5A8, next action is 1.
Jan 4 09:48:33.001: NTP Core(DEBUG): receive: packet given to process_packet
Jan 4 09:48:33.001: NTP Core(DEBUG): Peer becomes reachable, poll set to 6.
Jan 4 09:48:33.001: NTP Core(INFO): peer 10.15.99.1 event 'event_reach' (0x84) status 'unreach, 1 event, event_reach' (0x14)
Jan 4 09:48:33.001: NTP Core(INFO): synchronized to 10.15.99.1, stratum 2
Jan 4 09:48:33.001: NTP: step(0x00000081.27F01065): local_offset = 0x00000000.00000000, curtime = 0xE75FC9F1.005ED1F4
Jan 4 09:50:42.157: NTP Core(NOTICE): time reset 129.156006 s
Jan 4 09:50:42.157: NTP Core(DEBUG): bcast client cleared
Jan 4 09:51:41.448: NTP recv pkt on v4 socket, pak = 0x021F9650.
Jan 4 09:51:41.448: NTP message received from 10.15.99.1 on interface 'Vlan99' (255.255.255.255):
Jan 4 09:51:41.448:
01-04-2023 02:20 AM - edited 01-04-2023 02:21 AM
You are so so welcome friend,
yes debug ntp packet save us today.
happy new year.
01-04-2023 02:48 AM
Hello,
can you post the full running configs (sh run) of both the 1841 and the 2960 ?
01-05-2023 08:41 AM
Here are the two outputs of the running config.
The devices are set up for test purposes only and have no security mechanisms set up!
Router:
rt1812#sho run
Building configuration...
Current configuration : 3051 bytes
!
! Last configuration change at 11:01:12 GMT Wed Jan 4 2023
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname rt1812
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$gCSE$Hd7rNDhD7b98ZBjc5S.cS1
enable password xyz
!
no aaa new-model
clock timezone GMT 1
clock summer-time EU recurring last Sun Mar 1:00 last Sun Oct 2:00
!
!
dot11 syslog
!
!
ip cef
no ip dhcp use vrf connected
ip dhcp excluded-address 10.15.25.1 10.15.25.2
ip dhcp excluded-address 10.15.99.1 10.15.99.2
ip dhcp excluded-address 10.15.10.1 10.15.10.100
ip dhcp excluded-address 10.15.10.150 10.15.10.254
!
ip dhcp pool vPool10
network 10.15.10.0 255.255.255.0
default-router 10.15.10.1
dns-server 157.161.9.7 8.8.8.8
!
ip dhcp pool vPool25
network 10.15.25.0 255.255.255.240
default-router 10.15.25.1
dns-server 157.161.9.7 8.8.8.8
!
ip dhcp pool vPool99
network 10.15.99.0 255.255.255.240
default-router 10.15.99.1
dns-server 157.161.9.7 8.8.8.8
!
!
ip name-server 157.161.9.7
ip name-server 8.8.8.8
!
multilink bundle-name authenticated
!
!
!
!
archive
log config
hidekeys
!
!
!
!
!
interface FastEthernet0
no ip address
shutdown
duplex auto
speed auto
!
interface FastEthernet1
ip address dhcp
ip nat outside
ip virtual-reassembly
duplex auto
speed auto
!
interface BRI0
no ip address
encapsulation hdlc
shutdown
isdn point-to-point-setup
!
interface FastEthernet2
switchport access vlan 10
!
interface FastEthernet3
switchport access vlan 10
!
interface FastEthernet4
switchport access vlan 10
!
interface FastEthernet5
switchport access vlan 10
!
interface FastEthernet6
switchport trunk native vlan 99
switchport mode trunk
!
interface FastEthernet7
switchport mode trunk
!
interface FastEthernet8
switchport trunk native vlan 99
switchport trunk allowed vlan 1,25,99,1002-1005
switchport mode trunk
ntp broadcast
!
interface FastEthernet9
shutdown
!
interface Vlan1
no ip address
shutdown
!
interface Vlan10
ip address 10.15.10.1 255.255.255.0
ip nat inside
ip virtual-reassembly
ntp broadcast
!
interface Vlan25
ip address 10.15.25.1 255.255.255.240
ip nat inside
ip virtual-reassembly
!
interface Vlan99
ip address 10.15.99.1 255.255.255.240
ip nat inside
ip virtual-reassembly
ntp broadcast
!
interface Vlan12
no ip address
!
ip forward-protocol nd
!
!
no ip http server
no ip http secure-server
ip nat inside source static udp 192.168.10.104 51820 interface FastEthernet1 51820
ip nat inside source list 10 interface FastEthernet1 overload
ip nat inside source list 25 interface FastEthernet1 overload
ip nat inside source list 99 interface FastEthernet1 overload
!
access-list 10 permit 10.15.10.0 0.0.0.255
access-list 25 permit 10.15.25.0 0.0.0.15
access-list 99 permit 10.15.99.0 0.0.0.15
dialer-list 1 protocol ip permit
!
!
!
!
!
!
control-plane
!
!
line con 0
line aux 0
line vty 0 4
password xyz
login
!
ntp clock-period 17180072
ntp update-calendar
ntp server 192.33.96.102
end
*******************************************************
Switch:
sw1#sho run
Building configuration...
Current configuration : 1591 bytes
!
! Last configuration change at 10:29:20 GMT Wed Jan 4 2023
!
version 15.0
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname sw1
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
clock timezone GMT 1 0
clock summer-time eu recurring last Sun Mar 1:00 last Sun Oct 2:00
system mtu routing 1500
!
!
!
!
!
!
!
!
!
!
spanning-tree mode pvst
spanning-tree extend system-id
!
vlan internal allocation policy ascending
!
!
!
!
!
interface FastEthernet0/1
!
interface FastEthernet0/2
!
interface FastEthernet0/3
!
interface FastEthernet0/4
!
interface FastEthernet0/5
!
interface FastEthernet0/6
!
interface FastEthernet0/7
!
interface FastEthernet0/8
!
interface FastEthernet0/9
!
interface FastEthernet0/10
!
interface FastEthernet0/11
!
interface FastEthernet0/12
!
interface FastEthernet0/13
switchport trunk native vlan 99
switchport trunk allowed vlan 1,25,99,1002-1005
switchport mode trunk
!
interface FastEthernet0/14
!
interface FastEthernet0/15
!
interface FastEthernet0/16
!
interface FastEthernet0/17
!
interface FastEthernet0/18
!
interface FastEthernet0/19
!
interface FastEthernet0/20
!
interface FastEthernet0/21
!
interface FastEthernet0/22
!
interface FastEthernet0/23
!
interface FastEthernet0/24
!
interface GigabitEthernet0/1
!
interface GigabitEthernet0/2
!
interface Vlan1
no ip address
no ip route-cache
!
interface Vlan99
ip address 10.15.99.2 255.255.255.240
no ip route-cache
ntp broadcast client
!
ip http server
ip http secure-server
!
!
line con 0
line vty 5 15
!
end
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