The fstab is fine
blkid
/dev/mmcblk0p1: UUID="85ffa85e-4784-4cfd-93bb-db6f93f8ef0b" TYPE="ext4" PARTUUID="cac5f6cc-01"
/dev/mmcblk2p1: UUID="f817ad43-5219-4498-a6ac-f14e5ac76fd3" TYPE="ext4" PARTUUID="8bc978ec-01"
/dev/mmcblk0: PTUUID="cac5f6cc" PTTYPE="dos"
/dev/mmcblk2: PTUUID="8bc978ec" PTTYPE="dos"
root@orangepizeroplus2:/mnt/tt/etc# cat fstab
# <file system> <mount point> <type> <options> <dump> <pass>
tmpfs /tmp tmpfs defaults,nosuid 00
UUID=f817ad43-5219-4498-a6ac-f14e5ac76fd3 / ext4 defaults,noatime,nodiratime,commit=600,errors=remount-ro,x-gvfs-hide 0 1
I assume, i have to add to armbianEnv.txt
rootdev=UUID=f817ad43-5219-4498-a6ac-f14e5ac76fd3
rootfstype=ext4
root@orangepizeroplus2:/mnt/tt/boot# cat armbianEnv.txt
# $OpenBSD: sshd_config,v 1.100 2016/08/15 12:32:04 naddy Exp $
# This is the sshd server system-wide configuration file. See
# sshd_config(5) for more information.
# This sshd was compiled
usbstoragequirks=0x2537:0x1066:u,0x2537:0x1068:u