[root@emy-17 ~]# zoneadm -z b2 halt
[root@emy-17 ~]# zonecfg -z b2 info brand
brand: bhyve
[root@emy-17 ~]# uname -a
SunOS emy-17 5.11 joyent_20171230T062027Z i86pc i386 i86pc
[root@emy-17 ~]# zoneadm -z b2 boot; zlogin -C b2
Then grub appears
[root@emy-17 ~]# zoneadm -z b2 halt
[root@emy-17 ~]# zonecfg -z b2 info brand
brand: bhyve
[root@emy-17 ~]# uname -a
SunOS emy-17 5.11 joyent_20171230T062027Z i86pc i386 i86pc
[root@emy-17 ~]# zoneadm -z b2 boot; zlogin -C b2
Then grub appears