C9300 PTP recovery from FAULTY state

[kguilbert]

I have a C9300 switch running IOS XE 17.6.6. When using PTP in any configuration, if a port loses a link, the PTP state for that port transitions to FAULTY. This seems to be a terminal state. If the port loses a link because it has to be unplugged briefly, is there a way to have the switch transition back out of the FAULTY state without user interaction?

[Giuseppe Larosa]

Hello @kguilbert ,

I have reviewed the following configuration guide for PTP

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst9300/software/release/16-11/configuration_guide/lyr2/b_1611_lyr2_9300_cg/configuring_precision_time_protocol__ptp_.html#task_lhv_hfy_zcb

what do you see in the output of show ptp interface ?

in the config guide above we see a last line like the following:

>>

Sync fault limit: 500000000

this looks like to be a timer for fault .

what do you do now to recover from Faulty state ?

Do you unconfigure PTP on the interface and then you reconfigure it ?

Device(config-if)# no ptp enable

or you use a shut / no shut of the interface ?

Edit:

I have seen a command introduced in 17.5 that allows to set a port as primary ( providing clock ) it may be something to try if feasible for you.

>> Support was introduced to set a port permanently as primary (master) using the ptp role primary command. 

Hope to help

Giuseppe