How can I find out whether a specific RedHat release (RHEL4, RHEL5...) contains a certain package (or a certain version of a package)? For Debian and Ubuntu, there's packages.debian.org and packages.ubuntu.com; is there a similar web site for RedHat?
Note: I don't want to have to install all the releases just to check some package version :-)
The best you can do, as it seems, is to check the FTP directories of the source packages:
Keep in mind that RedHat has the habit of patching software to hell and back, so the version number might not have to much in common with the actual release, especially for the kernel.
For starters: http://distrowatch.com/table.php?distribution=redhat has a list of the important versions, but certainly does not list all package versions.
显然，Red Hat 的 RHEL 发行版确实有这样一个在线软件包列表，但只有付费的 Red Hat 客户才能访问它:-(
顺便提一句。类似的问题（针对 CentOS）：https ://serverfault.com/questions/239205/official-online-rpm-package-browser-search-for-centos
由于 RedHat 和 CENTOS 非常相似，您可以通过查看 CENTOS 存储库中相应版本的软件包来获得一个不错的列表。转至以下站点之一并转至您的 RedHat / CENTOS 版本并找到软件包。CENTOS 版本与 RedHat 版本一致。
例如，对于带有 RedHat 6.3（或 CENTOS 6.3）的 i386 系统，请查看以下站点：http: //vault.centos.org/6.3/os/i386/Packages/
我不保证它会是一对一的映射，但它应该非常接近。
看起来 Fedora 现在正在处理一个在线软件包列表（PackageDB - 请参阅http://fedoraproject.org/wiki/Infrastructure/PackageDatabase）。当前版本可在https://admin.fedoraproject.org/pkgdb/获得。不过，它似乎并不了解所有 RHEL4/RHEL5 软件包。
If you have your yum repositories set, you can use "yum search " to see if it exists, or "yum list" to see all available packages.
注意：通过“浏览”rsync://镜像而不是ftp://镜像，您可以方便地使用通配符过滤文件，而不必等待几分钟来下载所有包的海量而全面的列表。