Timestamp Tagging (TTAG) on N9K configuration

[GL_kz]

Hi,

We are trying to configure TTAG on N9K-C93180-YC-EX running version 9.3.7 and it doesn't work.

PTP is configured properly and the N9K get the time from the PTP server.

With the configuration below, we can ping between the end points but we don't see the time stamp (probably because of the command ttag-strip).

interface Eth1/1
ttag
ttag-marker enable
ttag-strip
switchport
switchport access vlan 10
spanning-tree port type edge
no shutdown
!
interface Eth1/2
ttag
ttag-marker enable
ttag-strip
switchport
switchport access vlan 10
spanning-tree port type edge
no shutdown
!
interface Eth1/3
desc To-PTP-Server
ptp
ttag
switchport
switchport access vlan 10
spanning-tree port type edge
no shutdown
!
interface Eth1/5
desc To-Wireshark
switchport
switchport monitor

When configured as follows, we can't ping between the endpoints, and of course we also don't see the ttag.

interface Eth1/1
ttag
ttag-marker enable
switchport
switchport access vlan 10
spanning-tree port type edge
no shutdown
!
interface Eth1/2
ttag
ttag-marker enable
switchport
switchport access vlan 10
spanning-tree port type edge
no shutdown
!
interface Eth1/3
desc To-PTP-Server
ptp
ttag
switchport
switchport access vlan 10
spanning-tree port type edge
no shutdown
!
interface Eth1/5
desc To-Wireshark
switchport
switchport monitor

Anyone has any experience with configuring ttag and might have any suggestion?

Please advise,

[Hanfeng Cai]

1. TTAG-Strip will definitely remove TTAG header by egress port. That's why you didn't see it.

2. I think you should capture packet from e1/2's endpoint directly instead rely on SPAN. Ping failed already points e1/2 endpoint may not recognize pky which is with ttag header.