http://cdimage.ubuntu.com/ubuntu-base/releases/18.04/release/
ubuntu-base-18.04-base-arm64.tar.gz
ubuntu-base-18.04-base-armhf.tar.gz
Refer to qemu mode to mount ARM/Ubuntu/Rootfs
1. Qemu4 user mode source build/static for Chroot/ARM rootfs
Build qemu4 source on Ubuntu18/X86_64
https://blog.csdn.net/hushui/article/details/103791704
2. Qemu2.x user mode/Ubuntu18 for Chroot/ARM qemu-user-static/CONFIG_BINFMT_MISC/Ubuntu/ARM/Rootfs
Default install qemu2 on Ubuntu18/X86_64 to mount ARM rootfs/Ubuntu18
https://blog.csdn.net/hushui/article/details/103806109
3. systemd vs Ubuntu16. Refer to ubuntu-base-16.04-core-armhf enable systemctl/systemd/dev-ttyAMA0 https://blog.csdn.net/hushui/article/details/103764254
++
root@ShSwDev2:/# uname -a
Linux ShSwDev2 4.4.0-142-generic #168-Ubuntu SMP Wed Jan 16 21:00:45 UTC 2019 aarch64 aarch64 aarch64 GNU/Linu
root@lake-Latitude-5491:/# apt list --installed |grep systemd
WARNING: apt does not have a stable CLI interface. Use with caution in scripts.libsystemd0/bionic,now 237-3ubuntu10 arm64 [installed,upgradable to: 237-3ubuntu10.33]
root@lake-Latitude-5491:/#
root@lake-Latitude-5491:/# which init <<<< Issue no init/systemd in ubuntu-base-18.04-base-arm64/armhf
root@lake-Latitude-5491:/# which systemd
root@lake-Latitude-5491:/# which busybox
root@lake-Latitude-5491:/# which ps
/bin/ps
root@lake-Latitude-5491:/# which init
root@lake-Latitude-5491:/#
root@lake-Latitude-5491:/# apt list --installed |grep systemd <<<<< Ubuntu18/arm/default no systemd
WARNING: apt does not have a stable CLI interface. Use with caution in scripts.
libsystemd0/bionic,now 237-3ubuntu10 arm64 [installed]
root@ShSwDev2:/# apt list |grep systemd
WARNING: apt does not have a stable CLI interface. Use with caution in scripts.
libnss-systemd/bionic 237-3ubuntu10 arm64
libpam-systemd/bionic 237-3ubuntu10 arm64
libsystemd-dev/bionic 237-3ubuntu10 arm64
libsystemd0/bionic,now 237-3ubuntu10 arm64 [installed]
python3-systemd/bionic 234-1build1 arm64
systemd/bionic 237-3ubuntu10 arm64 <<<<<<<< apt install systemd/Ubuntu18 arm system
systemd-sysv/bionic 237-3ubuntu10 arm64 <<<<<<<< apt install systemd/Ubuntu18 arm system
### Ubuntu16/ARM/default Compre
root@ShSwDev2:/# apt list --installed |grep systemd
WARNING: apt does not have a stable CLI interface. Use with caution in scripts.
libsystemd0/xenial,now 229-4ubuntu4 armhf [installed]
systemd/xenial,now 229-4ubuntu4 armhf [installed]
systemd-sysv/xenial,now 229-4ubuntu4 armhf [installed]