"[Errno 14] HTTP Error 400: Bad Request" エラーで yum に失敗する

Issue

• 以下のエラーで yum に失敗します。

# yum update
Loaded plugins: product-id, rhnplugin, security, subscription-manager
Updating Red Hat repositories.
https://cdn.redhat.com/content/dist/rhel/server/5/5Server/i386/cf-tools/1.0/os/repodata/repomd.xml:[Errno 14] HTTP Error 400:Bad Request
Trying other mirror.
Error:Cannot retrieve repository metadata (repomd.xml) for repository: rhel-5-server-cf-tools-1-rpms.Please verify its path and try again

• 以下のエラーで yum update に失敗します。

Error Downloading Packages: 
  libstdc++-4.1.2-46.el5_4.2.x86_64: failed to retrieve getPackage/libstdc++-4.1.2-46.el5_4.2.x86_64.rpm from rhel-x86_64-server-5 
error was [Errno 14] HTTP Error 400:Bad Request 
  nscd-2.5-42.el5_4.3.x86_64: failed to retrieve getPackage/nscd-2.5-42.el5_4.3.x86_64.rpm from rhel-x86_64-server-5 
error was [Errno 14] HTTP Error 400:Bad Request 
8.x86_64.rpm from rhel-x86_64-server-5 
error was [Errno 14] HTTP Error 400:Bad Request