Renan

After checking, /var/log/armbian-hardware-monitor.log 
I detected btrfs did not exist in my build. I went back to lib/configuration.sh and saw btrfs-progs package was not installed if BUILD_MINIMAL = YES. 
 
if [[ "$BUILD_MINIMAL" != "yes"  ]]; then     # Essential packages     PACKAGE_LIST="$PACKAGE_LIST bridge-utils build-essential fbset \         iw wpasupplicant sudo linux-base crda \         wireless-regdb unattended-upgrades \         console-setup unicode-data initramfs-tools \         ca-certificates expect iptables automake html2text \         bison flex libwrap0-dev libssl-dev libnl-3-dev libnl-genl-3-dev keyboard-configuration"     # Non-essential packages     PACKAGE_LIST_ADDITIONAL="$PACKAGE_LIST_ADDITIONAL alsa-utils btrfs-progs dosfstools iotop stress screen \         ntfs-3g vim pciutils evtest pv libfuse2 libdigest-sha-perl \         libproc-processtable-perl aptitude dnsutils f3 haveged hdparm rfkill vlan bash-completion \         hostapd git ethtool unzip ifenslave libpam-systemd iperf3 \         software-properties-common libnss-myhostname f2fs-tools avahi-autoipd iputils-arping qrencode sunxi-tools" fi  
I changed then this from
 
PACKAGE_LIST="bc cpufrequtils device-tree-compiler fping fake-hwclock psmisc chrony parted dialog \         ncurses-term sysfsutils toilet figlet u-boot-tools usbutils openssh-server \         nocache debconf-utils python3-apt"  
to
 
PACKAGE_LIST="bc btrfs-progs cpufrequtils device-tree-compiler fping fake-hwclock psmisc chrony parted dialog \         ncurses-term sysfsutils toilet figlet u-boot-tools usbutils openssh-server \         nocache debconf-utils python3-apt"  
And now it works. I suppose btrfs-progs needs to be added to PACKAGE_LIST (or DEBOOTSTRAP_LIST?) only in the case ROOTFS_TYPE=btrfs and irrespectively of BUILD_MINIMAL.

After checking, /var/log/armbian-hardware-monitor.log 
I detected btrfs did not exist in my build. I went back to lib/configuration.sh and saw btrfs-progs package was not installed if BUILD_MINIMAL = YES. 
 
if [[ "$BUILD_MINIMAL" != "yes"  ]]; then     # Essential packages     PACKAGE_LIST="$PACKAGE_LIST bridge-utils build-essential fbset \         iw wpasupplicant sudo linux-base crda \         wireless-regdb unattended-upgrades \         console-setup unicode-data initramfs-tools \         ca-certificates expect iptables automake html2text \         bison flex libwrap0-dev libssl-dev libnl-3-dev libnl-genl-3-dev keyboard-configuration"     # Non-essential packages     PACKAGE_LIST_ADDITIONAL="$PACKAGE_LIST_ADDITIONAL alsa-utils btrfs-progs dosfstools iotop stress screen \         ntfs-3g vim pciutils evtest pv libfuse2 libdigest-sha-perl \         libproc-processtable-perl aptitude dnsutils f3 haveged hdparm rfkill vlan bash-completion \         hostapd git ethtool unzip ifenslave libpam-systemd iperf3 \         software-properties-common libnss-myhostname f2fs-tools avahi-autoipd iputils-arping qrencode sunxi-tools" fi  
I changed then this from
 
PACKAGE_LIST="bc cpufrequtils device-tree-compiler fping fake-hwclock psmisc chrony parted dialog \         ncurses-term sysfsutils toilet figlet u-boot-tools usbutils openssh-server \         nocache debconf-utils python3-apt"  
to
 
PACKAGE_LIST="bc btrfs-progs cpufrequtils device-tree-compiler fping fake-hwclock psmisc chrony parted dialog \         ncurses-term sysfsutils toilet figlet u-boot-tools usbutils openssh-server \         nocache debconf-utils python3-apt"  
And now it works. I suppose btrfs-progs needs to be added to PACKAGE_LIST (or DEBOOTSTRAP_LIST?) only in the case ROOTFS_TYPE=btrfs and irrespectively of BUILD_MINIMAL.

After checking, /var/log/armbian-hardware-monitor.log 
I detected btrfs did not exist in my build. I went back to lib/configuration.sh and saw btrfs-progs package was not installed if BUILD_MINIMAL = YES. 
 
if [[ "$BUILD_MINIMAL" != "yes"  ]]; then     # Essential packages     PACKAGE_LIST="$PACKAGE_LIST bridge-utils build-essential fbset \         iw wpasupplicant sudo linux-base crda \         wireless-regdb unattended-upgrades \         console-setup unicode-data initramfs-tools \         ca-certificates expect iptables automake html2text \         bison flex libwrap0-dev libssl-dev libnl-3-dev libnl-genl-3-dev keyboard-configuration"     # Non-essential packages     PACKAGE_LIST_ADDITIONAL="$PACKAGE_LIST_ADDITIONAL alsa-utils btrfs-progs dosfstools iotop stress screen \         ntfs-3g vim pciutils evtest pv libfuse2 libdigest-sha-perl \         libproc-processtable-perl aptitude dnsutils f3 haveged hdparm rfkill vlan bash-completion \         hostapd git ethtool unzip ifenslave libpam-systemd iperf3 \         software-properties-common libnss-myhostname f2fs-tools avahi-autoipd iputils-arping qrencode sunxi-tools" fi  
I changed then this from
 
PACKAGE_LIST="bc cpufrequtils device-tree-compiler fping fake-hwclock psmisc chrony parted dialog \         ncurses-term sysfsutils toilet figlet u-boot-tools usbutils openssh-server \         nocache debconf-utils python3-apt"  
to
 
PACKAGE_LIST="bc btrfs-progs cpufrequtils device-tree-compiler fping fake-hwclock psmisc chrony parted dialog \         ncurses-term sysfsutils toilet figlet u-boot-tools usbutils openssh-server \         nocache debconf-utils python3-apt"  
And now it works. I suppose btrfs-progs needs to be added to PACKAGE_LIST (or DEBOOTSTRAP_LIST?) only in the case ROOTFS_TYPE=btrfs and irrespectively of BUILD_MINIMAL.