我在 CentOS -7 上尝试安装 openjdk-1.8.0 (& -devel) 时似乎遇到了障碍，yum 无法找到该包（没有可用的包 java-1.8.0-openjdk。）
http://mirror.centos.org/centos/7/updates/x86_64/Packages/甚至不是从这里。
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* base: mirrors.tripadvisor.com
* epel: s3-mirror-us-east-1.fedoraproject.org
* extras: mirror.vtti.vt.edu
No package java-1.8.0-openjdk available.
Error: Nothing to do
CentOS-Base.repo：
[base]
name=CentOS-$releasever - Base
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os&infra=$infra
#baseurl=http://mirror.centos.org/centos/$releasever/os/$basearch/
gpgcheck=1
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
#released updates
[updates]
name=CentOS-$releasever - Updates
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updates&infra=$infra
#baseurl=http://mirror.centos.org/centos/$releasever/updates/$basearch/
gpgcheck=1
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
#additional packages that may be useful
[extras]
name=CentOS-$releasever - Extras
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=extras&infra=$infra
#baseurl=http://mirror.centos.org/centos/$releasever/extras/$basearch/
gpgcheck=1
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-$releasever - Plus
#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=centosplus&infra=$infra
baseurl=http://mirror.centos.org/centos/$releasever/centosplus/$basearch/
gpgcheck=1
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
更具体地说是 centos-release-7-4.1708.el7.centos.x86_64
答案1
yum search jdk
结果：
java-1.8.0-openjdk.x86_64 : OpenJDK Runtime Environment
java-1.8.0-openjdk-devel.x86_64 : OpenJDK Development Environment
因此你可以运行：
yum install java-1.8.0-openjdk.x86_64 java-1.8.0-openjdk-devel.x86_64
如果这不起作用，请尝试yum clean all并重复。
编辑：您还可以搜索您发布的 FTP repo 链接......
答案2
我估计
bash$ grep openjdk /etc/yum.conf
exclude=*.i?86 *openjdk* java*
并且不敢相信在其他所有事情上都花了很长时间。在删除排除项后现在可以工作了。非常天真！
答案3
根据以下输出，Java-1.8.0-openjdk似乎在更新
$ cat /etc/redhat-release
CentOS Linux release 7.4.1708 (Core)
$ yum list java-1.8.0-openjdk*
Loaded plugins: fastestmirror, langpacks, nvidia
Loading mirror speeds from cached hostfile
* base: mirrors.tripadvisor.com
* elrepo: repos.ord.lax-noc.com
* epel: mirror.math.princeton.edu
* extras: mirrors.greenmountainaccess.net
* nux-dextop: mirror.li.nux.ro
* updates: mirror.net.cen.ct.gov
Installed Packages
java-1.8.0-openjdk.x86_64 1:1.8.0.144-0.b01.el7_4 @updates
java-1.8.0-openjdk-headless.x86_64 1:1.8.0.144-0.b01.el7_4 @updates
Available Packages
java-1.8.0-openjdk.i686 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-accessibility.i686 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-accessibility.x86_64 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-accessibility-debug.i686 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-accessibility-debug.x86_64 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-debug.i686 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-debug.x86_64 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-demo.i686 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-demo.x86_64 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-demo-debug.i686 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-demo-debug.x86_64 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-devel.i686 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-devel.x86_64 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-devel-debug.i686 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-devel-debug.x86_64 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-headless.i686 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-headless-debug.i686 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-headless-debug.x86_64 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-javadoc.noarch 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-javadoc-debug.noarch 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-javadoc-zip.noarch 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-javadoc-zip-debug.noarch 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-src.i686 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-src.x86_64 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-src-debug.i686 1:1.8.0.144-0.b01.el7_4 updates
java-1.8.0-openjdk-src-debug.x86_64 1:1.8.0.144-0.b01.el7_4 updates
$
你应该跑yum 全部清理和/或yum 检查（需要一些时间）解决任何问题并重试...