vyatta@rtr-3# run generate vpn openvpn-key /config/auth/lala.key
Generating OpenVPN key to /config/auth/lala.key
Your new local OpenVPN key has been generated
[edit]
vyatta@rtr-3# set interfaces openvpn vtun0 shared-secret-key-file /config/auth/lala.key
[edit]
vyatta@rtr-3# commit
[edit]
vyatta@rtr-3# sudo cat /config/auth/lala.key
#
# 2048 bit OpenVPN static key
#
-----BEGIN OpenVPN Static key V1-----
[SNIP]
-----END OpenVPN Static key V1-----