完美解決CentOS8 yum安裝AppStream報錯，更新yum後無法makecache的問題
阿新 • • 發佈：2020-11-03
問題
CentOS 8 yum安裝軟體時，提示無法從AppStream下載
[root@C8-3 ~]# yum -y install httpd mariadb-server mariadb php php-mysql Repository AppStream is listed more than once in the configuration Repository extras is listed more than once in the configuration Repository PowerTools is listed more than once in the configuration Repository centosplus is listed more than once in the configuration Repository fasttrack is listed more than once in the configuration CentOS-8 - AppStream 0.0 B/s | 0 B 00:08 Failed to download metadata for repo 'AppStream' Error: Failed to download metadata for repo 'AppStream'
先排除網路問題
檢查網通不通，然後確定DNS解析是否正確。
[root@C8-3 ~]# ping baidu.com PING baidu.com (220.181.38.148) 56(84) bytes of data. 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=1 ttl=128 time=12.1 ms 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=2 ttl=128 time=12.2 ms 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=3 ttl=128 time=11.7 ms 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=4 ttl=128 time=13.5 ms 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=5 ttl=128 time=12.2 ms 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=6 ttl=128 time=12.1 ms 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=7 ttl=128 time=13.9 ms 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=8 ttl=128 time=11.4 ms 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=9 ttl=128 time=13.9 ms ^C --- baidu.com ping statistics --- 9 packets transmitted, 9 received, 0% packet loss, time 31ms rtt min/avg/max/mdev = 11.394/12.554/13.949/0.899 ms
有可能是所在網路環境在出口封了相應埠，需用其他方式，比如VPN解決。
更換國內yum源
我們無法使用CentOS原生yum源就是因為網路問題，你懂的。
為了快，更換國內yum源，推薦阿里雲yum或者騰訊yum。網易沒落了。
- 阿里yum源： https://developer.aliyun.com/mirror/centos
- 騰雲yum源： https://mirrors.tencent.com/help/centos.html
[root@C8-3 ~]# mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.backup.3 [root@C8-3 ~]# wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.cloud.tencent.com/repo/centos8_base.repo --2020-11-02 20:51:42-- http://mirrors.cloud.tencent.com/repo/centos8_base.repo Resolving mirrors.cloud.tencent.com (mirrors.cloud.tencent.com)... 111.231.36.190 Connecting to mirrors.cloud.tencent.com (mirrors.cloud.tencent.com)|111.231.36.190|:80... connected. HTTP request sent, awaiting response... 200 OK Length: 1792 (1.8K) [application/octet-stream] Saving to: ‘/etc/yum.repos.d/CentOS-Base.repo’ /etc/yum.repos.d/Ce 100%[==================>] 1.75K --.-KB/s in 0s 2020-11-02 20:51:46 (65.6 MB/s) - ‘/etc/yum.repos.d/CentOS-Base.repo’ saved [1792/1792]
清理之前的yum快取
[root@C8-3 ~]# yum clean all
Repository AppStream is listed more than once in the configuration
Repository extras is listed more than once in the configuration
Repository PowerTools is listed more than once in the configuration
Repository centosplus is listed more than once in the configuration
Repository fasttrack is listed more than once in the configuration
18 files removed
建立新的快取
[root@C8-3 ~]# yum makecache
Repository AppStream is listed more than once in the configuration
Repository extras is listed more than once in the configuration
Repository PowerTools is listed more than once in the configuration
Repository centosplus is listed more than once in the configuration
Repository fasttrack is listed more than once in the configuration
CentOS-8 - AppStream 0.0 B/s | 0 B 00:04
Failed to download metadata for repo 'AppStream'
Error: Failed to download metadata for repo 'AppStream'
makecache的時候報錯了！
解決makecahe報錯
- Failed to download metadata for repo 'AppStream'
- Error: Failed to download metadata for repo 'AppStream' # 下載meta資訊失敗
問題的原因
先看看CentOS7的yum.repos.d
[21:19:17 root@C7-1 ~]#ll /etc/yum.repos.d/
total 44
-rw-r--r--. 1 root root 2523 Oct 27 22:47 CentOS-Base.repo
-rw-r--r--. 1 root root 1664 Sep 5 2019 CentOS-Base.repo.bak
-rw-r--r--. 1 root root 1309 Sep 5 2019 CentOS-CR.repo
-rw-r--r--. 1 root root 649 Sep 5 2019 CentOS-Debuginfo.repo
-rw-r--r--. 1 root root 314 Sep 5 2019 CentOS-fasttrack.repo
-rw-r--r--. 1 root root 630 Sep 5 2019 CentOS-Media.repo
-rw-r--r--. 1 root root 1331 Sep 5 2019 CentOS-Sources.repo
-rw-r--r--. 1 root root 6639 Sep 5 2019 CentOS-Vault.repo
-rw-r--r--. 1 root root 951 Oct 2 2017 epel.repo
-rw-r--r--. 1 root root 1050 Oct 2 2017 epel-testing.repo
再看看CentOS8的yum.repos.d
[root@C8-3 ~]# ll /etc/yum.repos.d/
total 56
-rw-r--r--. 1 root root 815 Oct 28 02:33 CentOS-AppStream.repo
-rw-r--r--. 1 root root 1792 Mar 25 2020 CentOS-Base.repo
-rw-r--r--. 1 root root 712 Jan 2 2020 CentOS-Base.repo.backup
-rw-r--r--. 1 root root 1792 Mar 25 2020 CentOS-Base.repo.backup.3
-rw-r--r--. 1 root root 798 Jan 2 2020 CentOS-centosplus.repo
-rw-r--r--. 1 root root 1043 Jan 2 2020 CentOS-CR.repo
-rw-r--r--. 1 root root 668 Jan 2 2020 CentOS-Debuginfo.repo
-rw-r--r--. 1 root root 756 Jan 2 2020 CentOS-Extras.repo
-rw-r--r--. 1 root root 338 Jan 2 2020 CentOS-fasttrack.repo
-rw-r--r--. 1 root root 738 Jan 2 2020 CentOS-HA.repo
-rw-r--r--. 1 root root 928 Jan 2 2020 CentOS-Media.repo
-rw-r--r--. 1 root root 736 Jan 2 2020 CentOS-PowerTools.repo
-rw-r--r--. 1 root root 1382 Jan 2 2020 CentOS-Sources.repo
-rw-r--r--. 1 root root 74 Jan 2 2020 CentOS-Vault.repo
CentOS 8 多了一個 CentOS-AppStream.repo
這是出問題的關鍵。
檢視一下CentOS-AppStream.repo
[root@C8-3 ~]# cat /etc/yum.repos.d/CentOS-AppStream.repo.bac
# CentOS-AppStream.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.
#
#
[AppStream]
name=CentOS-$releasever - AppStream
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=AppStream&infra=$infra
baseurl=http://mirror.centos.org/$contentdir/$releasever/AppStream/$basearch/os/
#mirrorlist=http://mirror.centos.org/$contentdir/$releasever/AppStream/$basearch/os/
gpgcheck=1
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial
解決問題的方法
我們在替換yum源的時候，按照映象網站的操作方式，只替換了CentOS-Base.repo。
可是在CentOS8中，CentOS-AppStream.repo的內容沒有更新。
解決方法有兩種
- 直接刪除掉CentOS-AppStream.repo這個檔案。（不推薦）
- 將CentOS-AppStream.repo檔案中的連結更新
解決問題
檢視跟新後的CentOS-Base.repo檔案
[root@C8-3 ~]# cat /etc/yum.repos.d/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.
#
#
[BaseOS]
name=Qcloud centos OS - $basearch
baseurl=http://mirrors.cloud.tencent.com/centos/$releasever/BaseOS/$basearch/os/
enabled=1
gpgcheck=1
gpgkey=http://mirrors.cloud.tencent.com/centos/RPM-GPG-KEY-CentOS-Official
[centosplus]
name=Qcloud centosplus - $basearch
baseurl=http://mirrors.cloud.tencent.com/centos/$releasever/centosplus/$basearch/os/
enabled=0
gpgcheck=1
gpgkey=http://mirrors.cloud.tencent.com/centos/RPM-GPG-KEY-CentOS-Official
[extras]
name=Qcloud centos extras - $basearch
baseurl=http://mirrors.cloud.tencent.com/centos/$releasever/extras/$basearch/os/
enabled=1
gpgcheck=1
gpgkey=http://mirrors.cloud.tencent.com/centos/RPM-GPG-KEY-CentOS-Official
[fasttrack]
name=Qcloud centos fasttrack - $basearch
baseurl=http://mirrors.cloud.tencent.com/centos/$releasever/fasttrack/$basearch/os/
enabled=0
gpgcheck=1
gpgkey=http://mirrors.cloud.tencent.com/centos/RPM-GPG-KEY-CentOS-Official
[AppStream]
name=Qcloud centos AppStream - $basearch
baseurl=http://mirrors.cloud.tencent.com/centos/$releasever/AppStream/$basearch/os/
enabled=0
gpgcheck=1
gpgkey=http://mirrors.cloud.tencent.com/centos/RPM-GPG-KEY-CentOS-Official
[PowerTools]
name=Qcloud centos PowerTools - $basearch
baseurl=http://mirrors.cloud.tencent.com/centos/$releasever/PowerTools/$basearch/os/
enabled=0
gpgcheck=1
gpgkey=http://mirrors.cloud.tencent.com/centos/RPM-GPG-KEY-CentOS-Official
替換更新
- 找到跟新後CentOS-Base.repo中[AppStream]標籤內的內容並複製
[AppStream]
name=Qcloud centos AppStream - $basearch
baseurl=http://mirrors.cloud.tencent.com/centos/$releasever/AppStream/$basearch/os/
enabled=0
gpgcheck=1
gpgkey=http://mirrors.cloud.tencent.com/centos/RPM-GPG-KEY-CentOS-Official
- 開啟CentOS-AppStream.repo，註釋掉原有內容，並插入新內容
[root@C8-3 ~]# vim /etc/yum.repos.d/CentOS-AppStream.repo
#[AppStream]
#name=CentOS-$releasever - AppStream
#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=AppStream&infra=$infra
#baseurl=http://mirror.centos.org/$contentdir/$releasever/AppStream/$basearch/os/
#mirrorlist=http://mirror.centos.org/$contentdir/$releasever/AppStream/$basearch/os/
#gpgcheck=1
#enabled=1
#pgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial
[AppStream]
name=Qcloud centos AppStream - $basearch
baseurl=http://mirrors.cloud.tencent.com/centos/$releasever/AppStream/$basearch/os/
enabled=0
gpgcheck=1
gpgkey=http://mirrors.cloud.tencent.com/centos/RPM-GPG-KEY-CentOS-Official
我們要養成修改內容時使用註釋而不是刪除的操作方法，用來對比前後差異，出問題了取消掉註釋就可以了。
問題解決
重新執行yum makecache，操作成功
[root@C8-3 ~]# yum makecache
Repository AppStream is listed more than once in the configuration
Repository extras is listed more than once in the configuration
Repository PowerTools is listed more than once in the configuration
Repository centosplus is listed more than once in the configuration
Repository fasttrack is listed more than once in the configuration
Qcloud centos OS - x86_64 119 kB/s | 2.2 MB 00:19
Qcloud centos extras - x86_64 477 B/s | 8.1 kB 00:17
Metadata cache created.
小貼士：
修改檔案的良好習慣：
- 先備份需要修改的檔案，cp a a.bac
- 在修改檔案內容時，新增新內容前，對原內容使用註釋而非刪除