NTP Configuration Example

In the example shown in NTP Configuration Example, SW#1 synchronizes its clock from the 0-3.us.pool.ntp.org timer server, and provides the synchronized clock information to SW#2 as a unicast message, and to SW#3 as a broadcast message.

SW#2 configures SW#1 as a time server using a normal unicast message. It also has a local clock (127.127.1.1) with a stratum level of 10. SW#3 is configured as broadcast client without specific server information. For security purposes, SW#2 and SW#3 use RSA Data Security, Inc. MD5 (Message-Digest algorithm 5) Message-Digest Algorithm authentication with a key index of 100.

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NTP Configuration Example
../Graphics/NTP_Service_diag.png

SW#1 Configuration

create vlan internet
create vlan toSW2
create vlan toSW3
config vlan internet add port 1
config vlan toSW2 add port 2
config vlan toSW3 add port 3
config vlan internet ipaddress 10.45.203.74/24
config vlan toSW2 ipaddress 100.1.1.1/24
config vlan toSW3 ipaddress 102.1.1.1/24
config iproute add default 10.45.203.1 vr vr-default
enable ntp
create ntp key 100  md5 EXTREME
config ntp key 100 trusted
enable ntp vlan internet
enable ntp vlan toSW2
enable ntp vlan toSW3
enable ntp vlan toSW3 broadcast-server key 100
config ntp server add 0.us.pool.ntp.org
config ntp server add 1.us.pool.ntp.org
config ntp server add 2.us.pool.ntp.org
config ntp server add 3.us.pool.ntp.org
config ntp local-clock stratum 10

SW#2 Configuration

create vlan toSW1
config vlan toSW1 add port 1
config vlan toSW1 ipaddress 100.1.1.2/24
enable ntp
enable ntp vlan toSW1
config ntp server add 100.1.1.1

SW#3 Configuration

create vlan toSW1
config vlan toSW1 add port 1
config vlan toSW1 ipaddress 102.1.1.2/24
enable ntp
enable ntp broadcast-client
create ntp key 100 md5 EXTREME
config ntp key 100 trusted
enable ntp vlan toSW1

NTP Configuration Example over Multiple VRs

Switch SW#1 Configuration

create vlan v2 -- in vr VR-Mgmt
create vlan v5 -- in vr VR-Default
create vlan v3 -- in vr test (user-VR)
create vlan v6 -- in vr test (user-VR)
config vlan v2 ipaddress 10.127.7.33/24
config vlan v5 ipaddress 5.1.1.5/24
config vlan v3 ipaddress 10.127.7.60/24
config vlan v5 add port <port towards SW#2>
config vlan v6 add port <port towards SW#3>
config vlan v2 add port <port connected to reach reference clock>
config vlan v3 add port <port connected to reach reference clock>
enable ntp vr test
enable ntp vr VR-Default
enable ntp vr VR-Mgmt
enable ntp vlan v3
enable ntp vlan v6
enable ntp vlan v2
enable ntp vlan v5
enable ntp vlan Mgmt
configure ntp server add 128.138.140.44 initial-burst vr VR-Default
configure ntp server add 128.138.141.172 initial-burst vr VR-Default
configure ntp server add 129.6.15.28 initial-burst vr test
configure ntp server add 129.6.15.29 initial-burst vr test
configure ntp server add 129.6.15.30 initial-burst vr test
configure ntp server add 2.us.pool.ntp.org initial-burst vr test
configure ntp server add 204.152.184.72 initial-burst vr VR-Mgmt
configure ntp server add 24.56.178.140 initial-burst vr VR-Default
configure ntp server add 64.113.32.5 initial-burst vr VR-Default
configure ntp server add 66.199.22.67 initial-burst vr VR-Mgmt
configure ntp server add 98.175.203.200 initial-burst vr VR-Mgmt

SW#2 Configuration

create vlan v5 -- in vr VR-Default
config vlan v5 add port <port towards SW#1>
config vlan v5 ipaddress 5.1.1.6/24
enable ntp vr VR-Default
enable ntp vlan v5
configure ntp server add 5.1.1.5 initial-burst vr VR-Default

SW#3 Configuration

create vlan v6 -- in vr test (user-VR)
config vlan v6 ipaddress 6.1.1.7/24
config vlan v6 add port <port towards SW#1>
enable ntp vr test
enable ntp vlan v6
configure ntp server add 6.1.1.6 initial-burst vr test