Cisco devices are not commonly members of your domain. They are separate entities so it’s important that they reference a source for time synchronization. This is especially important with logging.
Cisco devices support the NTP standard for time synchronization. I set up an NTP server and point it to pool.ntp.org. I then and point my Cisco devices to this. I’ll use internal IP of 10.100.1.50. Here are the configuration instructions.
1. Log in to the device.
2. Enter enable mode (en)
3. Enter configure terminal mode (conf t)
4. Enter the following command to sync with the server. **NOTE: source is the interface that can contact the NTP server. It must be able to contact 10.100.1.50**
ntp server 10.100.1.50 source **inside**
5. Enter the following to set the time zone.
clock timezone EST -5
6. Enter the following to set daylight savings time (second Sunday in March, First Sunday in November at 3am the clock will be adjusted one hour)
clock summer-time Eastern recurring 2 Sun Mar 3:00 1 Sun Nov 3:00
7. Save your configuration