Debian系统遇到无法安装命令的时候，提示错误：E: package wget has no installation candidate
如图：
说明系统默认的源地址无法连接，更换为国内的源后即可安装。
//1.先备份
cp /etc/apt/sources.list /etc/apt/sources.list.bak
//2.清空原来的源
echo " " > /etc/apt/sources.list
//3.写国内源
echo "deb https://mirrors.aliyun.com/debian stable main contrib non-free">>/etc/apt/sources.list
echo "deb https://mirrors.aliyun.com/debian stable-updates main contrib non-free">>/etc/apt/sources.list
//4.清空缓存
apt-get clean
apt-get update
========================其他国内源参考================
一键更改源为163
代码 复制 - 运行
echo 'deb http://mirrors.163.com/debian/ buster main non-free contrib
deb http://mirrors.163.com/debian/ buster-updates main non-free contrib
deb http://mirrors.163.com/debian/ buster-backports main non-free contrib
deb-src http://mirrors.163.com/debian/ buster main non-free contrib
deb-src http://mirrors.163.com/debian/ buster-updates main non-free contrib
deb-src http://mirrors.163.com/debian/ buster-backports main non-free contrib
deb http://mirrors.163.com/debian-security/ buster/updates main non-free contrib
deb-src http://mirrors.163.com/debian-security/ buster/updates main non-free contrib
' > /etc/apt/sources.list
一键更改源为腾讯源
代码 复制 - 运行
echo 'deb http://mirrors.cloud.tencent.com/debian/ buster main non-free contrib
deb http://mirrors.cloud.tencent.com/debian-security buster/updates main
deb http://mirrors.cloud.tencent.com/debian/ buster-updates main non-free contrib
deb http://mirrors.cloud.tencent.com/debian/ buster-backports main non-free contrib
deb-src http://mirrors.cloud.tencent.com/debian-security buster/updates main
deb-src http://mirrors.cloud.tencent.com/debian/ buster main non-free contrib
deb-src http://mirrors.cloud.tencent.com/debian/ buster-updates main non-free contrib
deb-src http://mirrors.cloud.tencent.com/debian/ buster-backports main non-free contrib
' > /etc/apt/sources.list
