1. 更換國內鏡像源
最近安裝了fedroa 30 linux，但下載默認是官方源，yum install的時候經常timeout。
使用說明
下載fedora-163.repo和fedora-updates-163.repo, 放入/etc/yum.repos.d/
運行yum makecache生成緩存
推薦操作方法，，wget下載這兩個文件:
# cd /etc/yum.repos.d
# wget http://mirrors.163.com/.help/fedora-163.repo
# wget http://mirrors.163.com/.help/fedora-updates-163.repo
# yum makecache
[root@fc30-hadoop yum.repos.d]# wget http://mirrors.163.com/.help/fedora-163.repo
--2019-12-17 04:40:28-- http://mirrors.163.com/.help/fedora-163.repo
Resolving mirrors.163.com (mirrors.163.com)... 59.111.0.251
Connecting to mirrors.163.com (mirrors.163.com)|59.111.0.251|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 1108 (1.1K) [application/octet-stream]
Saving to: ‘fedora-163.repo’
fedora-163.repo 100%[=======================================================================================>] 1.08K --.-KB/s in 0s
2019-12-17 04:40:29 (13.3 MB/s) - ‘fedora-163.repo’ saved [1108/1108]
[root@fc30-hadoop yum.repos.d]# wget http://mirrors.163.com/.help/fedora-updates-163.repo
--2019-12-17 04:40:52-- http://mirrors.163.com/.help/fedora-updates-163.repo
Resolving mirrors.163.com (mirrors.163.com)... 59.111.0.251
Connecting to mirrors.163.com (mirrors.163.com)|59.111.0.251|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 1069 (1.0K) [application/octet-stream]
Saving to: ‘fedora-updates-163.repo’
fedora-updates-163.repo 100%[=======================================================================================>] 1.04K --.-KB/s in 0s
2019-12-17 04:40:52 (49.5 MB/s) - ‘fedora-updates-163.repo’ saved [1069/1069]
[root@fc30-hadoop yum.repos.d]# yum makecache
Repository updates is listed more than once in the configuration
Repository updates-debuginfo is listed more than once in the configuration
Repository updates-source is listed more than once in the configuration
Repository fedora is listed more than once in the configuration
Repository fedora-debuginfo is listed more than once in the configuration
Repository fedora-source is listed more than once in the configuration
Cannot find a valid baseurl for repo: 163_fedora
Fedora 30 - x86_64 - 163.com 88 B/s | 4.8 kB 00:55
Failed to synchronize cache for repo 'fedora'
Fedora Modular 30 - x86_64 373 B/s | 8.2 kB 00:22
Fedora 30 - x86_64 - Updates - 163.com 241 B/s | 8.1 kB 00:34
Fedora Modular 30 - x86_64 - Updates 198 B/s | 7.1 kB 00:36
Ignoring repositories: 163_fedora, fedora
Metadata cache created.