在 Ubuntu 下，我创建了一个 Centos 8 LXD 容器：
lxc launch images:centos/8 centoscontainer
然后，我使用 登录到容器lxc exec centoscontainer /bin/bash。
我是root，我可以正常访问网络：
# ping mirrorlist.centos.org
PING mirrorlist.centos.org (147.75.69.225) 56(84) bytes of data.
64 bytes from packet04.centos.org (147.75.69.225): icmp_seq=1 ttl=43 time=213 ms
64 bytes from packet04.centos.org (147.75.69.225): icmp_seq=2 ttl=43 time=209 ms
64 bytes from packet04.centos.org (147.75.69.225): icmp_seq=3 ttl=43 time=206 ms
^C
但是当我尝试使用 yum install 时，它失败了，我不明白为什么：
# yum install -y java-1.8.0-openjdk-devel
CentOS Linux 8 - BaseOS 0.0 B/s | 0 B 05:59
Errors during downloading metadata for repository 'baseos':
- Curl error (7): Couldn't connect to server for http://mirrorlist.centos.org/?release=8&arch=x86_64&repo=BaseOS&infra=stock [Failed to connect to mirrorlist.centos.org port 80: Connection timed out]
Error: Failed to download metadata for repo 'baseos': Cannot prepare internal mirrorlist: Curl error (7): Couldn't connect to server for http://mirrorlist.centos.org/?release=8&arch=x86_64&repo=BaseOS&infra=stock [Failed to connect to mirrorlist.centos.org port 80: Connection timed out]
有什么方法可以解决这个问题？