Network Time Protocol (Cisco)

Technology: Network Services

Area: Network Time Protocol (NTP)

Vendor: Cisco

Software: IOS 12.X , 15.X

Platform: Catalyst Switches, Routers

The Network Time Protocol (NTP) is able to synchronize the time of day between time servers and clients which are distributed so that the events can correlate when receiving system logs and other time-specific events from multiple network devices. NTP uses the User Datagram Protocol (UDP) as its transport protocol.

To configure an NTP server of IP 192.0.2.10 as a time reference:

switch# configure terminal
switch(config)# ntp server 192.0.2.10

If NTP server supports authentication, use key command:

switch(config)# ntp server 192.0.2.10 key Cisco

To configure ntp in ipv6 environment:

switch(config)# ntp peer 2001:0db8::4101

To verify ntp settings:

switch(config)# show ntp peers
--------------------------------------------------
Peer IP Address Serv/Peer
--------------------------------------------------
2001:0db8::4101 Peer (configured)
192.0.2.10 Server (configured)

Use also:

switch(config)# show ntp association
switch(config)# show ntp status