安装Linux容器并尝试更新存储库结尾为“服务不可用”
> root@cce54fe33d6d:/var/www/html# apt-get update
> Ign:1 http://security.debian.org/debian-security stretch/updates InRelease
> Ign:2 http://deb.debian.org/debian stretch InRelease
> .
> .
> .
> E: Failed to fetch http://deb.debian.org/debian/dists/stretch-updates/main/binary-amd64/Packages
> 503 Service Unavailable [IP: 149.20.4.15 80]
> E: Failed to fetch http://deb.debian.org/debian/dists/buster/main/binary-amd64/Packages
> 503 Service Unavailable [IP: 149.20.4.15 80]
> E: Failed to fetch http://deb.debian.org/debian/dists/buster-updates/main/binary-amd64/Packages
> 503 Service Unavailable [IP: 149.20.4.15 80]
主机（Windows 10）在激活的防火墙防御程序下运行，日志显示：
2019-07-12 08:04:08 ALLOW TCP myIP*** 149.20.4.15 55367 80 0 - 0 0 0 - - - SEND
2019-07-12 08:04:08 ALLOW TCP myIP*** 149.20.4.15 55370 80 0 - 0 0 0 - - - SEND
看来，我可以发送但不能接收。不是吗？