I'm trying to ... yum groupinstall "Development Tools" on a reasonably current 5.5 system and getting massive mirror failures... is there a problem, or is this my employer's network messing up? (45/74): rpm-build-4.4.2.3-20.el5_5.1.i386.rpm | 302 kB 00:03 http://mirror.singleedge.com/pub/centos/5.5/addons/i386/CentOS/imake-1.0.2-3.i386.rpm: [Errno 14] HTTP Error 404: Not Found Trying other mirror. http://mirror.nwresd.org/pub/centos/5.5/addons/i386/CentOS/imake-1.0.2-3.i386.rpm: [Errno 14] HTTP Error 404: Not Found Trying other mirror. http://hpc.arc.georgetown.edu/mirror/centos/5.5/addons/i386/CentOS/imake-1.0.2-3.i386.rpm: [Errno 14] HTTP Error 404: Not Found Trying other mirror. http://mirror.its.uidaho.edu/pub/centos/5.5/addons/i386/CentOS/imake-1.0.2-3.i386.rpm: [Errno 14] HTTP Error 404: Not Found Trying other mirror. http://mirror.flhsi.com/centos/5.5/addons/i386/CentOS/imake-1.0.2-3.i386.rpm: [Errno 14] HTTP Error 404: Not Found Trying other mirror. http://mirror.highspeedweb.net/CentOS/5.5/addons/i386/CentOS/imake-1.0.2-3.i386.rpm: [Errno 14] HTTP Error 404: Not Found Trying other mirror. http://mirror.atlanticmetro.net/centos/5.5/addons/i386/CentOS/imake-1.0.2-3.i386.rpm: [Errno 14] HTTP Error 404: Not Found Trying other mirror. http://ftp.lug.udel.edu/pub/centos/5.5/addons/i386/CentOS/imake-1.0.2-3.i386.rpm: [Errno 14] HTTP Error 404: Not found Trying other mirror. http://mirror.vcu.edu/pub/gnu%2Blinux/centos/5.5/addons/i386/CentOS/imake-1.0.2-3.i386.rpm: [Errno 12] Timeout: <urlopen error timed out> Trying other mirror. http://mirrors.greenmountainaccess.net/centos/5.5/addons/i386/CentOS/imake-1.0.2-3.i386.rpm: [Errno 14] HTTP Error 404: Not Found Trying other mirror. http://mirror.singleedge.com/pub/centos/5.5/addons/i386/CentOS/libXaw-1.0.2-8.1.i386.rpm: [Errno 14] HTTP Error 404: Not Found Trying other mirror. http://mirror.nwresd.org/pub/centos/5.5/addons/i386/CentOS/libXaw-1.0.2-8.1.i386.rpm: [Errno 14] HTTP Error 404: Not Found Trying other mirror. http://hpc.arc.georgetown.edu/mirror/centos/5.5/addons/i386/CentOS/libXaw-1.0.2-8.1.i386.rpm: [Errno 14] HTTP Error 404: Not Found Trying other mirror. http://mirror.its.uidaho.edu/pub/centos/5.5/addons/i386/CentOS/libXaw-1.0.2-8.1.i386.rpm: [Errno 14] HTTP Error 404: Not Found Trying other mirror. http://mirror.flhsi.com/centos/5.5/addons/i386/CentOS/libXaw-1.0.2-8.1.i386.rpm: [Errno 14] HTTP Error 404: Not Found Trying other mirror. http://mirror.highspeedweb.net/CentOS/5.5/addons/i386/CentOS/libXaw-1.0.2-8.1.i386.rpm: [Errno 14] HTTP Error 404: Not Found Trying other mirror. http://mirror.atlanticmetro.net/centos/5.5/addons/i386/CentOS/libXaw-1.0.2-8.1.i386.rpm: [Errno 14] HTTP Error 404: Not Found Trying other mirror. http://ftp.lug.udel.edu/pub/centos/5.5/addons/i386/CentOS/libXaw-1.0.2-8.1.i386.rpm: [Errno 4] IOError: <urlopen error (111, 'Connection refused')> Trying other mirror.