基于learning armbian step(4) 的总结，我们来实践一下，接下来的会把整个构建的log都贴出来：
vmuser@vmuser-virtual-machine:~/qemu-arm$ sudo apt-get install qemu-user-static
[sudo] password for vmuser:
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following additional packages will be installed:
binfmt-support
The following NEW packages will be installed:
binfmt-support qemu-user-static
0 upgraded, 2 newly installed, 0 to remove and 325 not upgraded.
Need to get 7,753 kB of archives.
After this operation, 86.1 MB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://mirrors.aliyun.com/ubuntu xenial/main amd64 binfmt-support amd64 2.1.6-1 [50.7 kB]
Get:2 http://mirrors.aliyun.com/ubuntu xenial-updates/universe amd64 qemu-user-static amd64 1:2.5+dfsg-5ubuntu10.34 [7,702 kB]
Fetched 7,753 kB in 8s (910 kB/s)
Selecting previously unselected package binfmt-support.
(Reading database ... 276761 files and directories currently installed.)
Preparing to unpack .../binfmt-support_2.1.6-1_amd64.deb ...
Unpacking binfmt-support (2.1.6-1) ...
Selecting previously unselected package qemu-user-static.
Preparing to unpack .../qemu-user-static_1%3a2.5+dfsg-5ubuntu10.34_amd64.deb ...
Unpacking qemu-user-static (1:2.5+dfsg-5ubuntu10.34) ...
Processing triggers for systemd (229-4ubuntu21.15) ...
Processing triggers for ureadahead (0.100.0-19) ...
Processing triggers for man-db (2.7.5-1) ...
Setting up binfmt-support (2.1.6-1) ...
Setting up qemu-user-static (1:2.5+dfsg-5ubuntu10.34) ...
Processing triggers for systemd (229-4ubuntu21.15) ...
Processing triggers for ureadahead (0.100.0-19) ...
vmuser@vmuser-virtual-machine:~/qemu-arm$ sudo apt install debootstrap
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
debootstrap
0 upgraded, 1 newly installed, 0 to remove and 325 not upgraded.
Need to get 37.2 kB of archives.
After this operation, 262 kB of additional disk space will be used.
Get:1 http://mirrors.aliyun.com/ubuntu xenial-updates/main amd64 debootstrap all 1.0.78+nmu1ubuntu1.6 [37.2 kB]
Fetched 37.2 kB in 0s (357 kB/s)
Selecting previously unselected package debootstrap.
(Reading database ... 276841 files and directories currently installed.)
Preparing to unpack .../debootstrap_1.0.78+nmu1ubuntu1.6_all.deb ...
Unpacking debootstrap (1.0.78+nmu1ubuntu1.6) ...
Processing triggers for man-db (2.7.5-1) ...
Setting up debootstrap (1.0.78+nmu1ubuntu1.6) ...
We can use qemu-debootstrap to building ubuntu rootfs .
vmuser@vmuser-virtual-machine:~/qemu-arm$ sudo qemu-debootstrap --verbose --arch=arm64 --variant=buildd xenial ubuntu_arm64_xenial http://mirrors.ustc.edu.cn/ubuntu-ports
[sudo] password for vmuser:
Ok , we get it.
I: Configuring gcc-5...
I: Configuring libstdc++-5-dev:arm64...
I: Configuring gcc...
I: Configuring g++-5...
I: Configuring g++...
I: Configuring build-essential...
I: Configuring libc-bin...
I: Base system installed successfully.
Now we can get the ubuntu rootfs capacity
vmuser@vmuser-virtual-machine:~/qemu-arm$ du -h ubuntu_arm64_xenial/
1.2M ubuntu_arm64_xenial/var/cache/debconf
12K ubuntu_arm64_xenial/var/cache/ldconfig
4.0K ubuntu_arm64_xenial/var/cache/apt/archives/partial
54M ubuntu_arm64_xenial/var/cache/apt/archives
54M ubuntu_arm64_xenial/var/cache/apt
55M ubuntu_arm64_xenial/var/cache
4.0K ubuntu_arm64_xenial/var/tmp
68M ubuntu_arm64_xenial/var
318M ubuntu_arm64_xenial/
If you want to custom your rootfs , your can add build args , qemu-debootstrap will transmit args to debootstrap ,
so learn debootstrap usage, read fonts can help you customization you ubuntu rootfs.
vmuser@vmuser-virtual-machine:~/qemu-arm$ debootstrap --help
Usage: debootstrap [OPTION]... <suite> <target> [<mirror> [<script>]]
Bootstrap a Debian base system into a target directory.
--help display this help and exit
--version display version information and exit
--verbose don't turn off the output of wget
--download-only download packages, but don't perform installation
--print-debs print the packages to be installed, and exit
--arch=A set the architecture to install (use if no dpkg)
[ --arch=powerpc ]
--include=A,B,C adds specified names to the list of base packages
--exclude=A,B,C removes specified packages from the list
--components=A,B,C use packages from the listed components of the
archive
--variant=X use variant X of the bootstrap scripts
(currently supported variants: buildd, fakechroot,
scratchbox, minbase)
minbase: 只包含必要的包和apt；
buildd: 包含编译工具包
fakechroot: 包含不用root权限的包
scratchbox: 包含scratchbox(交叉编译工具链)相关包
--keyring=K check Release files against keyring K
--no-check-gpg avoid checking Release file signatures
--force-check-gpg force checking Release file signatures
(also disables automatic fallback to HTTPS in case
of a missing keyring), aborting otherwise
--no-resolve-deps don't try to resolve dependencies automatically
--unpack-tarball=T acquire .debs from a tarball instead of http
--make-tarball=T download .debs and create a tarball (tgz format)
--second-stage-target=DIR
Run second stage in a subdirectory instead of root
(can be used to create a foreign chroot)
(requires --second-stage)
--extractor=TYPE override automatic .deb extractor selection
(supported: dpkg-deb ar)
--debian-installer used for internal purposes by debian-installer
--private-key=file read the private key from file
--certificate=file use the client certificate stored in file (PEM)
--no-check-certificate do not check certificate against certificate authorities
Verify arm64 ubuntu rootfs:
# cp /usr/bin/qemu-aarch64-static ubuntu_arm64_xenial/usr/bin/
# mount proc ubuntu_arm64_xenial/proc -t proc
# mount sysfs ubuntu_arm64_xenial/sys -t sysfs
# cp /etc/hosts ubuntu_arm64_xenial/etc/hosts
# cp /etc/resolv.conf ubuntu_arm64_xenial/etc/resolv.conf
# chroot ubuntu_arm64_xenial/
root@vmuser-virtual-machine:/# ls ---- 》we got it, running arm rootfs in X86 host
bin boot dev etc home lib media mnt opt proc root run sbin srv sys tmp usr var
root@vmuser-virtual-machine:/# ifconfig
bash: ifconfig: command not found
root@vmuser-virtual-machine:/# apt install net-tools
Reading package lists... Done
Building dependency tree... Done
The following NEW packages will be installed:
net-tools
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
Need to get 165 kB of archives.
After this operation, 688 kB of additional disk space will be used.
Get:1 http://ports.ubuntu.com/ubuntu-ports xenial/main arm64 net-tools arm64 1.60-26ubuntu1 [165 kB]
Fetched 165 kB in 2s (79.9 kB/s)
perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
LANGUAGE = "en_US",
LC_ALL = (unset),
LC_PAPER = "zh_CN.UTF-8",
LC_NUMERIC = "zh_CN.UTF-8",
LC_IDENTIFICATION = "zh_CN.UTF-8",
LC_MEASUREMENT = "zh_CN.UTF-8",
LC_NAME = "zh_CN.UTF-8",
LC_TELEPHONE = "zh_CN.UTF-8",
LC_ADDRESS = "zh_CN.UTF-8",
LC_MONETARY = "zh_CN.UTF-8",
LC_TIME = "zh_CN.UTF-8",
LANG = "en_US.UTF-8"
are supported and installed on your system.
perl: warning: Falling back to the standard locale ("C").
debconf: delaying package configuration, since apt-utils is not installed
E: Can not write log (Is /dev/pts mounted?) - posix_openpt (2: No such file or directory)
Selecting previously unselected package net-tools.
(Reading database ... 11949 files and directories currently installed.)
Preparing to unpack .../net-tools_1.60-26ubuntu1_arm64.deb ...
Unpacking net-tools (1.60-26ubuntu1) ...
Setting up net-tools (1.60-26ubuntu1) ...
附加如下为构建桌面系统对应的源：
deb http://ports.ubuntu.com/ubuntu-ports/ xenial main restricted
deb-src http://ports.ubuntu.com/ubuntu-ports/ xenial main restricted
deb http://ports.ubuntu.com/ubuntu-ports/ xenial-updates main restricted
deb-src http://ports.ubuntu.com/ubuntu-ports/ xenial-updates main restricted
deb http://ports.ubuntu.com/ubuntu-ports/ xenial universe
deb-src http://ports.ubuntu.com/ubuntu-ports/ xenial universe
deb http://ports.ubuntu.com/ubuntu-ports/ xenial-updates universe
deb-src http://ports.ubuntu.com/ubuntu-ports/ xenial-updates universe
deb http://ports.ubuntu.com/ubuntu-ports/ xenial-backports main restricted
deb-src http://ports.ubuntu.com/ubuntu-ports/ xenial-backports main restricted
deb http://ports.ubuntu.com/ubuntu-ports/ xenial-security main restricted
deb-src http://ports.ubuntu.com/ubuntu-ports/ xenial-security main restricted
deb http://ports.ubuntu.com/ubuntu-ports/ xenial-security universe
deb-src http://ports.ubuntu.com/ubuntu-ports/ xenial-security universe
deb http://ports.ubuntu.com/ubuntu-ports/ xenial-security multiverse
deb-src http://ports.ubuntu.com/ubuntu-ports/ xenial-security multiverse
如下链接为ubuntu各版本的下载地址