Configuring or troubleshooting NTP on Cisco Router 2951 and 4507 Switch?

Question

Cisco

Good afternoon colleagues.
Right to the heart of the matter: the network has a router 2951 and L3 switch 4507. The router nates and manages traffic, qos and voice translation.
4507 is a dhsp server and vlan gateway. On it, the NTP server is configured 127.127.1.1 with the address stratum number 0.
The ntp peer 95.xxx command was present on the router (I did not remember the server address) and stratum number 16.
I removed the ntp settings from the router, since it was not working (Insane, unsynchronized )
As I understand it, the NTP locale on the switch does everything by itself. Debugs show that it distributes and Access Switches get time. But they differ: all phones in the office are 5-6 minutes behind. And this number is increasing every week. Please tell me what to do in this situation. Thanks

Answer 1

Askar A I will assume that there are no exact time sources in the local area and the router looks outside, it is preferable to set up clock synchronization on the router with external exact time servers (such as ru.pool.ntp.org, ntpX.vniiftri.ru, etc.) and the rest let the network equipment be synchronized with it (switches, servers).
As for the phones, a good question - here you need to look where the phones take the time from:
If you have CCME, then the time source is a router with CME (perhaps the same one that distributes the Internet).
In the case of CUCM, you need to configure ntp on CUCM (synchronization with the same router, for example).

Answer 2

Where does 4507 get its time from?