Cisco Mds 9000 Family Nx-Os Fundamentals Configuration Guide - Cisco MDS 9000 Series Configuration Manual

Tools for Software Configuration
By configuring an IP address as a peer, the Cisco NX-OS device will obtain and provide time as required.
The peer is capable of providing time on its own and is capable of having a server configured. If both of these
instances point to different time servers, your NTP service is more reliable. Even if the active server link is
lost, you can still maintain the correct time due to the presence of the peer.
If an active server fails, a configured peer helps in providing the NTP time. To ensure backup support if the
active server fails, provide a direct NTP server association and configure a peer.
If you only configure a peer, the most accurate peer takes on the role of the NTP server and the other peer
acts as a peer. Both devices end at the correct time if they have the correct time source or if they point to the
correct NTP source.
Not even a server down time will affect well-configured switches in the network. This figure displays a
network with two NTP stratum 2 servers and two switches.
Figure 2: NTP Peer and Server Association
In this configuration, the switches were configured as follows:
• Stratum-2 Server-1
• Stratum-2 Server-2
• Switch-1 IPv4 address-10.10.10.1
• Switch-1 NTP configuration
• Switch-2 IPv4 address-10.10.10.2
• Switch-2 NTP configuration

Cisco MDS 9000 Family NX-OS Fundamentals Configuration Guide

8
◦ IPv4 address-10.10.10.10
◦ IPv4 address-10.10.10.9
◦ NTP server 10.10.10.10
◦ NTP peer 10.10.10.2
◦ NTP server 10.10.10.9
Overview
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