For some strange reason, the vcp-snmp-statistics statement is hidden on the Juniper QFX platform – (if anybody knows why, please do tell!). This means  your individual virtual chassis VCP port statistics aren’t exposed in it’s entirety, which is pretty awful as monitoring VCP port errors are vital in virtual-chassis setups.

{master:0}[edit]
ben@qfx0# set virtual-chassis vcp-sn
                                                  ^
syntax error.
ben@qfx0# set virtual-chassis vcp-sn
                                                  ^
syntax error.ben@qfx0# set virtual-chassis vcp-sn?
No valid completions
{master:0}[edit]
ben@qfx0# set virtual-chassis vcp-snmp-statistics

{master:0}[edit]
ben@qfx0#

After committing changes, you should see the following in the logs, and likewise see more ports listed in your monitoring software of choice i.e. LibreNMS, Solarwinds, Zabbix etc.

Dec 27 10:59:12  qfx0 vccpd[1797]: Member 0, interface vcp-255/0/53 came up
Dec 27 10:59:12  qfx0 vccpd[1797]: Member 0, interface vcp-255/0/52 came up