One of the configured repositories failed (Unknown), and yum doesn't have enough cached data to continue.
1、问题
[root@localhost home]# yum install httpd
Loaded plugins: langpacks, product-id, subscription-manager
This system is not registered to Red Hat Subscription Management. You can use subscription-manager to register.
One of the configured repositories failed (Unknown),
and yum doesn't have enough cached data to continue. At this point the only
safe thing yum can do is fail. There are a few ways to work "fix" this:
1. Contact the upstream for the repository and get them to fix the problem.
2. Reconfigure the baseurl/etc. for the repository, to point to a working
upstream. This is most often useful if you are using a newer
distribution release than is supported by the repository (and the
packages for the previous distribution release still work).
3. Disable the repository, so yum won't use it by default. Yum will then
just ignore the repository until you permanently enable it again or use
--enablerepo for temporary usage:
yum-config-manager --disable <repoid>
4. Configure the failing repository to be skipped, if it is unavailable.
Note that yum will try to contact the repo. when it runs most commands,
so will have to try and fail each time (and thus. yum will be be much
slower). If it is a very temporary problem though, this is often a nice
compromise:
yum-config-manager --save --setopt=<repoid>.skip_if_unavailable=true
Cannot retrieve metalink for repository: epel/x86_64. Please verify its path and try again
2、解决方法，去掉baseurl前面的注释，将metalink注释掉
[root@localhost home]# cd /etc/yum.repos.d/
[root@localhost yum.repos.d]# ls
epel.repo epel-testing.repo packagekit-media.repo rhel7.repo
[root@localhost yum.repos.d]# vim epel.repo
[epel]
name=Extra Packages for Enterprise Linux 7 - $basearch
baseurl=http://download.fedoraproject.org/pub/epel/7/$basearch
#metalink=https://mirrors.fedoraproject.org/metalink?repo=epel-7&arch=$basearch&infra=$infra&content=$contentdir
failovermethod=priority
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-7
[epel-debuginfo]
name=Extra Packages for Enterprise Linux 7 - $basearch - Debug
baseurl=http://download.fedoraproject.org/pub/epel/7/$basearch/debug
#metalink=https://mirrors.fedoraproject.org/metalink?repo=epel-debug-7&arch=$basearch&infra=$infra&content=$contentdir
failovermethod=priority
enabled=0
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-7
gpgcheck=1
[epel-source]
name=Extra Packages for Enterprise Linux 7 - $basearch - Source
baseurl=http://download.fedoraproject.org/pub/epel/7/SRPMS
#metalink=https://mirrors.fedoraproject.org/metalink?repo=epel-source-7&arch=$basearch&infra=$infra&content=$contentdir
failovermethod=priority
enabled=0
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-7
gpgcheck=1
3、测试
[root@localhost yum.repos.d]# yum install httpd
Loaded plugins: langpacks, product-id, subscription-manager
This system is not registered to Red Hat Subscription Management. You can use subscription-manager to register.
epel | 4.7 kB 00:00:00
rhel7 | 4.1 kB 00:00:00
(1/3): epel/x86_64/group_gz | 95 kB 00:00:04
(2/3): epel/x86_64/updateinfo | 1.0 MB 00:00:13
(3/3): epel/x86_64/primary_db | 6.9 MB 00:01:24
Resolving Dependencies
--> Running transaction check
---> Package httpd.x86_64 0:2.4.6-17.el7 will be installed
--> Processing Dependency: httpd-tools = 2.4.6-17.el7 for package: httpd-2.4.6-17.el7.x86_64
--> Processing Dependency: libapr-1.so.0()(64bit) for package: httpd-2.4.6-17.el7.x86_64
--> Processing Dependency: libaprutil-1.so.0()(64bit) for package: httpd-2.4.6-17.el7.x86_64
--> Running transaction check
---> Package apr.x86_64 0:1.4.8-3.el7 will be installed
---> Package apr-util.x86_64 0:1.5.2-6.el7 will be installed
---> Package httpd-tools.x86_64 0:2.4.6-17.el7 will be installed
--> Finished Dependency Resolution
Dependencies Resolved
=====================================================================================================================================
Package Arch Version Repository Size
=====================================================================================================================================
Installing:
httpd x86_64 2.4.6-17.el7 rhel7 1.2 M
Installing for dependencies:
apr x86_64 1.4.8-3.el7 rhel7 103 k
apr-util x86_64 1.5.2-6.el7 rhel7 92 k
httpd-tools x86_64 2.4.6-17.el7 rhel7 77 k
Transaction Summary
=====================================================================================================================================
Install 1 Package (+3 Dependent packages)
Total download size: 1.4 M
Installed size: 4.3 M
Is this ok [y/d/N]: y
Downloading packages:
-------------------------------------------------------------------------------------------------------------------------------------
Total 174 MB/s | 1.4 MB 00:00:00
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Installing : apr-1.4.8-3.el7.x86_64 1/4
Installing : apr-util-1.5.2-6.el7.x86_64 2/4
Installing : httpd-tools-2.4.6-17.el7.x86_64 3/4
Installing : httpd-2.4.6-17.el7.x86_64 4/4
Verifying : httpd-tools-2.4.6-17.el7.x86_64 1/4
Verifying : apr-1.4.8-3.el7.x86_64 2/4
Verifying : apr-util-1.5.2-6.el7.x86_64 3/4
Verifying : httpd-2.4.6-17.el7.x86_64 4/4
Installed:
httpd.x86_64 0:2.4.6-17.el7
Dependency Installed:
apr.x86_64 0:1.4.8-3.el7 apr-util.x86_64 0:1.5.2-6.el7 httpd-tools.x86_64 0:2.4.6-17.el7
Complete!
