zfs list has no boot partition as specified

no zfs boot filesystem as specified in test case, but solaris boot partition shows in fdisk list. System operates normally, snapshot taken successfully of rpool/ROOT/ubuntu_qyi2f5.

# zfs mount
rpool/ROOT/ubuntu_qyi2f5 /
rpool/ROOT/ubuntu_qyi2f5/var/games /var/games
rpool/ROOT/ubuntu_qyi2f5/var/spool /var/spool
rpool/ROOT/ubuntu_qyi2f5/var/snap /var/snap
rpool/ROOT/ubuntu_qyi2f5/var/www /var/www
rpool/ROOT/ubuntu_qyi2f5/srv /srv
rpool/ROOT/ubuntu_qyi2f5/var/lib /var/lib
rpool/ROOT/ubuntu_qyi2f5/var/mail /var/mail
rpool/ROOT/ubuntu_qyi2f5/usr/local /usr/local
rpool/ROOT/ubuntu_qyi2f5/var/lib/apt /var/lib/apt
rpool/ROOT/ubuntu_qyi2f5/var/log /var/log
rpool/ROOT/ubuntu_qyi2f5/var/lib/AccountsService /var/lib/AccountsService
rpool/ROOT/ubuntu_qyi2f5/var/lib/NetworkManager /var/lib/NetworkManager
rpool/ROOT/ubuntu_qyi2f5/var/lib/dpkg /var/lib/dpkg

# zsysctl show
Name: rpool/ROOT/ubuntu_qyi2f5
ZSys: true
Last Used: current
Users:

$ fdisk -l
Disk /dev/sda: 596.17 GiB, 640135028736 bytes, 1250263728 sectors
Disk model: TOSHIBA MK6459GS
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: A5C2BBD7-0A3F-4822-B0E4-B5DC00B91CB7

Device Start End Sectors Size Type
/dev/sda1 2048 4095 2048 1M BIOS boot
/dev/sda2 4096 1054719 1050624 513M EFI System
/dev/sda3 1054720 5249023 4194304 2G Linux swap
/dev/sda4 5249024 9443327 4194304 2G Solaris boot
/dev/sda5 9443328 1250263694 1240820367 591.7G Solaris root