I had read that yes - thankyou.
unfortunately it shows the target interface configured with ethernet-switching, which doesn't seem to be acceptable to the acx5k.
I found the solution this morning by configuring a vlan and including the interface in the vlan as follows:
root@acx5048-pe-lab# show interfaces ge-0/0/8
description cust2;
mtu 9192;
encapsulation ethernet-bridge;
unit 0;
root@acx5048-pe-lab# show vlans
test {
vlan-id 100;
interface ge-0/0/8.0;
}
root@acx5048-pe-lab# run show forwarding-options analyzer
Analyzer name : pi
Mirror rate : 1
Maximum packet length : 0
State : up
Ingress monitored interfaces : ge-0/0/4.101
Egress monitored interfaces : ge-0/0/4.101
Output interface : ge-0/0/8.0