NCS – span

devices device asd-dc2-prd-sr-007

!
controller Optics0/0/0/16 speed 10g
!
controller Optics0/0/0/17 speed 10g
!
interface TenGigE0/0/0/16
description OMS-Span TX-1
no shutdown
transport-mode tx-only
!
interface TenGigE0/0/0/17
description OMS-Span TX-2
no shutdown
transport-mode tx-only

monitor-session 316 destination interface TenGigE0/0/0/16

monitor-session 317 destination interface TenGigE0/0/0/17

interface tunnel-ip1
ipv4 address 15.1.1.1 255.255.255.0
tunnel mode gre ipv4
tunnel source 172.16.3.24
tunnel destination 70.1.1.2

monitor-session 1 ethernet
destination interface tunnel-ip1

interface TenGigE0/0/0/0
description *** To IXIA 1/3 ***
ipv4 address 100.24.0.1 255.255.255.252
monitor-session 1 ethernet direction rx-only port-level

https://www.cisco.com/c/en/us/td/docs/iosxr/cisco8000/traffic-mirroring/b-traffic-mirroring-configuration-guide-cisco8k/erspan.html#configuration-guidelines-for-erspan-over-gre