armbian镜像源 vim /etc/apt/sources.list
如图将其中的源网址替换为下面的，还是复制比较保险

若是 Ubuntu ，将文件内容替换成以下内容：

deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports/ bionic main restricted universe multiverse
#deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports/ bionic main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports/ bionic-security main restricted universe multiverse
#deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports/ bionic-security main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports/ bionic-updates main restricted universe multiverse
#deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports/ bionic-updates main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports/ bionic-backports main restricted universe multiverse
#deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu-ports/ bionic-backports main restricted universe multiverse

若是 Debian，将文件内容替换成以下内容：

deb [ arch=arm64,armhf ] https://mirrors.tuna.tsinghua.edu.cn/debian/ stretch main contrib non-free
#deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ stretch main contrib non-free
deb [ arch=arm64,armhf ] https://mirrors.tuna.tsinghua.edu.cn/debian/ stretch-updates main contrib non-free
#deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ stretch-updates main contrib non-free
deb [ arch=arm64,armhf ] https://mirrors.tuna.tsinghua.edu.cn/debian/ stretch-backports main contrib non-free
#deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ stretch-backports main contrib non-free
deb [ arch=arm64,armhf ] https://mirrors.tuna.tsinghua.edu.cn/debian-security/ stretch/updates main contrib non-free
#deb-src https://mirrors.tuna.tsinghua.edu.cn/debian-security/ stretch/updates main contrib non-free
#deb [ arch=arm64,armhf ] https://mirrors.tuna.tsinghua.edu.cn/debian/ sid main contrib non-free

修改完成后，putty执行更新命令更新软件和软件包，不怕麻烦可以直接n1

apt-get update
apt-get upgrade

更换omv源：https://www.cryogeny.cn/182.html

公钥报错处理
将公钥添加至服务器，即终端中输入

apt-key adv --keyserver keyserver.ubuntu.com --recv-keys '公钥编码'

添加成功后终端输出为

gpg: key '公钥编码': public key "xxxxxx" imported
gpg: Total number processed: 1
gpg:                        imported: 1