Linux arm64架构修改软件源（国产系统UOS、银河麒麟测试可用，理论上支持所有arm的系统）

1.备份系统之前的源

cp /etc/apt/sources.list /etc/apt/sources.list.bak

2.修改源文件/etc/apt/sources.list

vim /etc/apt/sources.list

将原来的内容删除，将下面的源内容粘贴上。

这里推荐比较好的两个国内源

（1）阿里源（arm64，速度快，推荐）

deb http://mirrors.aliyun.com/ubuntu-ports/ xenial main
deb-src http://mirrors.aliyun.com/ubuntu-ports/ xenial main
 
deb http://mirrors.aliyun.com/ubuntu-ports/ xenial-updates main
deb-src http://mirrors.aliyun.com/ubuntu-ports/ xenial-updates main
 
deb http://mirrors.aliyun.com/ubuntu-ports/ xenial universe
deb-src http://mirrors.aliyun.com/ubuntu-ports/ xenial universe
deb http://mirrors.aliyun.com/ubuntu-ports/ xenial-updates universe
deb-src http://mirrors.aliyun.com/ubuntu-ports/ xenial-updates universe
 
deb http://mirrors.aliyun.com/ubuntu-ports/ xenial-security main
deb-src http://mirrors.aliyun.com/ubuntu-ports/ xenial-security main
deb http://mirrors.aliyun.com/ubuntu-ports/ xenial-security universe
deb-src http://mirrors.aliyun.com/ubuntu-ports/ xenial-security universe

（2）华为源（arm64,速度快，二者选其一）

deb https://repo.huaweicloud.com/ubuntu-ports/ bionic main restricted universe multiverse
deb-src https://repo.huaweicloud.com/ubuntu-ports/ bionic main restricted universe multiverse

deb https://repo.huaweicloud.com/ubuntu-ports/ bionic-security main restricted universe multiverse
deb-src https://repo.huaweicloud.com/ubuntu-ports/ bionic-security main restricted universe multiverse

deb https://repo.huaweicloud.com/ubuntu-ports/ bionic-updates main restricted universe multiverse
deb-src https://repo.huaweicloud.com/ubuntu-ports/ bionic-updates main restricted universe multiverse

deb https://repo.huaweicloud.com/ubuntu-ports/ bionic-backports main restricted universe multiverse
deb-src https://repo.huaweicloud.com/ubuntu-ports/ bionic-backports main restricted universe multiverse

## Not recommended
# deb https://repo.huaweicloud.com/ubuntu-ports/ bionic-proposed main restricted universe multiverse
# deb-src https://repo.huaweicloud.com/ubuntu-ports/ bionic-proposed main restricted universe multiverse

3.清除软件仓库缓存

apt-get clean

4.更新软件仓库

apt-get update

5.可能异常报错解决

如下图出现没有公钥，无法更新的情况

#通过以下命令解决
sudo apt-key adv --recv-keys --keyserver keyserver.ubuntu.com 40976EAF437D05B5 3B4FE6ACC0B21F32 （报错那里的无法验证的签名，提示什么就填什么）