When I use yum list java*,I get an error like the following：
[root@crucialer ~]# yum list java*
Repository extras is listed more than once in the configuration
Repository centosplus is listed more than once in the configuration
CentOS-8 - AppStream 17 kB/s | 2.3 kB 00:00
Errors during downloading metadata for repository 'AppStream':
- Status code: 404 for http://mirrors.cloud.aliyuncs.com/centos/8/AppStream/x86_64/os/repodata/repomd.xml (IP: 100.100.2.148)
Error: Failed to download metadata for repo 'AppStream': Cannot download repomd.xml: Cannot download repodata/repomd.xml: All mirrors were tried
[root@crucialer ~]# ping 100.100.2.148
PING 100.100.2.148 (100.100.2.148) 56(84) bytes of data.
64 bytes from 100.100.2.148: icmp_seq=1 ttl=102 time=1.94 ms
64 bytes from 100.100.2.148: icmp_seq=2 ttl=102 time=1.88 ms
64 bytes from 100.100.2.148: icmp_seq=3 ttl=102 time=2.08 ms
64 bytes from 100.100.2.148: icmp_seq=4 ttl=102 time=1.94 ms
64 bytes from 100.100.2.148: icmp_seq=5 ttl=102 time=1.93 ms
^C
--- 100.100.2.148 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 8ms
rtt min/avg/max/mdev = 1.883/1.953/2.078/0.076 ms
[root@crucialer ~]# ping www.baidu.com
PING www.a.shifen.com (180.101.49.12) 56(84) bytes of data.
64 bytes from 180.101.49.12 (180.101.49.12): icmp_seq=1 ttl=50 time=15.6 ms
64 bytes from 180.101.49.12 (180.101.49.12): icmp_seq=2 ttl=50 time=15.2 ms
64 bytes from 180.101.49.12 (180.101.49.12): icmp_seq=3 ttl=50 time=15.2 ms
64 bytes from 180.101.49.12 (180.101.49.12): icmp_seq=4 ttl=50 time=15.3 ms
^C
--- www.a.shifen.com ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 6ms
rtt min/avg/max/mdev = 15.223/15.331/15.581/0.210 ms
[root@crucialer yum.repos.d]# cat CentOS-Base.repo
# CentOS-Base.repo
#
# The mirror system uses the connecting IP address of the client and the
# update status of each mirror to pick mirrors that are updated to and
# geographically close to the client. You should use this for CentOS updates
# unless you are manually picking other mirrors.
#
# If the mirrorlist= does not work for you, as a fall back you can try the
# remarked out baseurl= line instead.
#
#
[base]
name=CentOS-$releasever - Base - 163.com
#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os
baseurl=http://mirrors.163.com/centos/$releasever/os/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7
#released updates
[updates]
name=CentOS-$releasever - Updates - 163.com
#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updates
baseurl=http://mirrors.163.com/centos/$releasever/updates/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7
#additional packages that may be useful
[extras]
name=CentOS-$releasever - Extras - 163.com
#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=extras
baseurl=http://mirrors.163.com/centos/$releasever/extras/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7
#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-$releasever - Plus - 163.com
baseurl=http://mirrors.163.com/centos/$releasever/centosplus/$basearch/
gpgcheck=1
enabled=0
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7
Any suggestions would be greatly appreciated.