root dispersion is 950.04 msec, peer dispersion is 3.38 msec
Configuration Examples for Implementing NTP
Configuring Poll-Based Associations: Example
The following example shows an NTP configuration in which the router’s system clock is configured to form
a peer association with the time server host at IP address 192.168.22.33, and to allow the system clock to be
synchronized by time server hosts at IP address 10.0.2.1 and 172.19.69.1:
ntp
server 10.0.2.1 minpoll 5 maxpoll 7
peer 192.168.22.33
server 172.19.69.1
Configuring Broadcast-Based Associations: Example
The following example shows an NTP client configuration in which interface 0/2/0/0 is configured to receive
NTP broadcast packets, and the estimated round-trip delay between an NTP client and an NTP broadcast
server is set to 2 microseconds:
ntp
interface tengige 0/2/0/0
broadcast client
exit
broadcastdelay 2
The following example shows an NTP server configuration where interface 0/2/0/2 is configured to be a
broadcast server:
ntp
interface tengige 0/2/0/2
broadcast
Configuring NTP Access Groups: Example
The following example shows a NTP access group configuration where the following access group restrictions
are applied:
•
Peer restrictions are applied to IP addresses that pass the criteria of the access list named peer-acl.
•
Serve restrictions are applied to IP addresses that pass the criteria of access list named serve-acl.
•
Serve-only restrictions are applied to IP addresses that pass the criteria of the access list named
serve-only-acl.
•
Query-only restrictions are applied to IP addresses that pass the criteria of the access list named
query-only-acl.
ntp
peer 10.1.1.1
peer 10.1.1.1
peer 10.2.2.2
Cisco ASR 9000 Series Aggregation Services Router System Management Configuration Guide, Release 5.1.x
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Implementing NTP
Configuration Examples for Implementing NTP