There's a number of timers you can adjust to control the frequency of various PTP messages on Nexus switches. However the values to configure are somewhat obtuse in Cisco's documentation. For example if you read the NX-OS config guide it says:
ptp announce [interval log seconds | timeout count]
Configures the interval between PTP announce messages on an interface or the number of PTP intervals before a timeout occurs on an interface.
The range for the PTP announcement interval is from 0 to 4 seconds, and the range for the interval timeout is from 2 to 10.
ptp delay request minimum interval log seconds
Configures the minimum interval allowed between PTP delay-request messages when the port is in the master state.
The range is from log(-6) to log(1) seconds.
ptp sync interval log seconds
Configures the interval between PTP synchronization messages on an interface.
The range for the PTP synchronization interval is from -3 log second to 1 log second
But how to interpret the log seconds values? It is described as the logarithmic mean interval in seconds. Which basically means number of seconds between PTP messages = 2 ^ interval value. For example 2 ^ -3 = 0.125s between messages, or 8 messages a second. So some common values are:
Interval 2 = 1 packet every 4 seconds
Interval 1 = 1 packet every 2 seconds
Interval 0 = 1 packet every second
Interval -1 = 1 packet every second
Interval -2 = 4 packets every second
Interval -3 = 8 packets every second
On a related note, by default Nexus switches can act as a grandmaster clock & Cisco best practice is to disable this functionality via "no ptp grandmaster-capable". As it is default configuration you'll need to use "show run all | inc ptp grandmaster-capable" in order to see the default command enabling it. Some further reading https://www.cisco.com/c/en/us/support/docs/ip/network-time-protocol-ntp/212139-Configure-and-troubleshoot-PTP-in-Nexus.html
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