NTP on the 4503 with cisco ios 12.1(19)EW

[EMBola]

Hello,

I'm trying to configure NTP on the 4503 with cisco ios 12.1(19)EW. Basically the NTP servers are external the 4503 is providing the inter-Vlan routing for the 5-2950's on the network. I also have an smtp gateway that's connected to the 4503, but it's not synchronizing it's clock.

The problem is that I need this smtp gateway to synchronize it's clock.

the conf on the 4503 is the following:
clock timezone EST -5
clock summer-time EDT recurring
clock calendar-valid
!
interface loopback 0
ip address 10.11.31.2 255.255.255.0
!
access-list 1 permit 10.11.31.91
access-list 2 permit A.B.65.70
access-list 2 permit A.B.65.69
!
ntp clock-period 17180016
ntp calendar-update
ntp master 2
ntp source loopback0
ntp access-group peer 2
ntp access-group serve 1
ntp server A.B.65.69 prefer
ntp server A.B.65.70

--------------------------------------------
Please indicate whether or not the conf on the 4503 is correct. I'm also concerned with the possibility that I might need NTP authentication for this to work. I'm also curious to know whether or not it's possible to have the 4503 sync with the SMTP gateway, since it's directly connected.

I appreciate the help.
Thank you,
Emanuel

 

[lui3]

Hey Emanuel,

The ntp master command is used like this

ntp master <stratum number>

in your case it looks like you are using an access list

stratum 2 does not indicate the main time server. your strat 2 server would need to be syncing with a strat 1 server before it will sync with other servers.

so to correct your configuration remove the access-lists and set the command to

ntp master
ntp update-calender

This should do what you want to do. If you want to mess around with authentication you can set up keys etc and get it to work. no need to specify ntp servers once the main 4503 clock is sync. I use them only for primary sync and then set the master command with

ntp master

good luck