Docker镜像加速配置失败的排查和修复教学

# 阿里云（需登录控制台获取）
https://<你的ID>.mirror.aliyuncs.com

# 腾讯云
https://mirror.ccs.tencentyun.com

# 中科大
https://docker.mirrors.ustc.edu.cn

sudo tee /etc/docker/daemon.json <<-'EOF'
{
  "registry-mirrors": [
    "https://docker.mirrors.ustc.edu.cn",
    "https://mirror.ccs.tencentyun.com",
    "https://hub-mirror.c.163.com"
  ],
  "max-concurrent-downloads": 10
}
EOF

# 临时生效
sudo echo "nameserver 223.5.5.5" > /etc/resolv.conf

# 永久生效（CentOS）
sudo nmcli connection modify eth0 ipv4.dns "223.5.5.5,119.29.29.29"
sudo systemctl restart NetworkManager

sudo tee /etc/sysctl.d/docker.conf <<-'EOF'
net.bridge.bridge-nf-call-iptables = 1
net.bridge.bridge-nf-call-ip6tables = 1
net.ipv4.ip_forward = 1
EOF
sudo sysctl -p

sudo systemctl stop docker docker.socket
sudo rm -f /var/run/docker.sock
sudo systemctl start docker

sudo usermod -aG docker $USER
newgrp docker  # 立即生效

sudo systemctl daemon-reload
sudo systemctl restart containerd
sudo systemctl restart docker
sleep 10  # 等待服务初始化

systemctl is-active docker  # 应返回 active
ls -l /var/run/docker.sock  # 权限应为 srw-rw----

# 使用CDN加速通道
docker pull dockerproxy.com/library/ubuntu:latest

# 查看实际下载速度
docker pull ubuntu:latest 2>&1 | awk '/MB/ {print $7}'

iptables -t nat -L DOCKER  # 应有容器转发规则

# 检查JSON格式
sudo python -m json.tool /etc/docker/daemon.json

# 检查生效配置
docker info | grep -A 15 "Docker Root Dir"

{
  "registry-mirrors": [
    "https://<阿里云ID>.mirror.aliyuncs.com",
    "https://dockerproxy.com"
  ],
  "dns": ["223.5.5.5", "8.8.8.8"],
  "log-driver": "json-file",
  "log-opts": {"max-size": "100m"}
}

date && sudo ntpdate cn.pool.ntp.org

docker system prune -af

sudo -i
docker ps