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Configuring 2811 to be NTP Client - help

I'm trying to configure all my routers to use NTP as a client. My NTP server is a linux server providing time to all my other network devices. Can someone point me in the right direction? I'm sure there is only a few commands I need to add to the config.


Re: Configuring 2811 to be NTP Client - help

As simple as:

clock timezone GMT-6 (or whatever your TZ is)

ntp server your_Linux_server_ip

to debug: show ntp ?

Re: Configuring 2811 to be NTP Client - help

Here's a sample

! always nice to have a loopback

interface Loopback0

ip address ip_address subnet_mask

! always nice to have an ACL

access-list 1 remark NTP-ACL

access-list 1 permit primary_ntp_server_ip_address

access-list 1 permit secondary_ntp_server_ip_address


ntp source loopback0

ntp access group peer 1

ntp server primary_ntp_server_ip_address prefer

ntp server secondary_ntp_server_ip_address

NTP Servers IP Address and Routers Loopback0 IP Address should be able to reach each other and if there is any filtering along their path (i.e. firewall, ACL) please allow TCP and UDP port 123 both ways.

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