https://nextheader.net/2014/10/31/snmp-stats-for-vcp-ports-in-virtual-chassis-fabricvcf/
Starting with 14.1X53-D10, the SNMP stats for VCP ports in Juniper VCF are available.
You will be able to retrieve the packet rate, bytes rate per second, the total number of bytes and packets per port per direction(in/out) among others.
To retrieve the stats, the following MIB object has to be used: jnxVirtualChassisPortEntry.
To activate the stats, a CLI command has to be configured under virtual-chassis hierarchy.
The command is:
set virtual-chassis vcp-snmp-statistics
{master:1}
lab@QFX5100-5> show snmp mib walk ascii jnxVirtualChassisPortInOctets
jnxVirtualChassisPortInOctets.0."vcp-255/0/48" = 56185113360
jnxVirtualChassisPortInOctets.0."vcp-255/0/49" = 35950458742
jnxVirtualChassisPortInOctets.1."vcp-255/0/48" = 21585094737
jnxVirtualChassisPortInOctets.1."vcp-255/0/49" = 39111551832
jnxVirtualChassisPortInOctets.2."vcp-255/0/48" = 39299502332
jnxVirtualChassisPortInOctets.2."vcp-255/0/49" = 36116503495
jnxVirtualChassisPortInOctets.3."vcp-255/0/48" = 21351278831
jnxVirtualChassisPortInOctets.3."vcp-255/0/49" = 55957682821
{master:1}
lab@QFX5100-5>