In VyOS 1.2.0-rolling+201806040337 rolling this results in:
$ show snmp v3 certificates sudo: /usr/bin/net-snmp-cert: command not found
Compare to VyOS 1.1.7 which ships this in libsnmp15:
$ dpkg -S /usr/bin/net-snmp-cert libsnmp15: /usr/bin/net-snmp-cert $ /usr/bin/net-snmp-cert Choose an operation: gencert - Generate a signed certificate genca - Generate a CA certificate gencsr - Generate a Certificate Signing Request signcsr - Sign a Certificate Signing Request
libsnmp15 is superseeded by libsnmp30 which no longer ship those utils (https://packages.debian.org/jessie/amd64/libsnmp30/filelist). This means that there is currently no easy way to create the SNMPv3 certificates.