删除企业源
rm -rf /etc/apt/sources.list.d/pve-enterprise.list
下载秘钥
wget http://mirrors.ustc.edu.cn/proxmox/debian/proxmox-ve-release-6.x.gpg -O /etc/apt/trusted.gpg.d/proxmox-ve-release-6.x.gpg
添加国内源
echo "deb http://mirrors.ustc.edu.cn/proxmox/debian/pve buster pve-no-subscription" >/etc/apt/sources.list.d/pve-install-repo.list
这里要注意下，很多教程会设置成错误 deb http://mirrors.ustc.edu.cn/proxmox/debian/pve strech pve-no-subscription造成无法升级为pve6.3
建议同时使用国内 debian 源，修改 /etc/apt/sources.list 文件，添加如下内容：
echo "deb http://mirrors.ustc.edu.cn/debian buster main contrib
deb http://mirrors.ustc.edu.cn/debian buster-updates main contrib
deb http://mirrors.ustc.edu.cn/debian-security buster/updates main contrib" > /etc/apt/sources.list
pve_ceph设置国内源
原配置文件：/etc/apt/sources.list.d/ceph.list
echo "deb http://mirrors.ustc.edu.cn/proxmox/debian/ceph-nautilus buster main" > /etc/apt/sources.list.d/ceph.list
最后执行
apt update
apt update && apt dist-upgrade
