Description of problem: Cannot find a valid baseurl for repo: core Version-Release number of selected component (if applicable): 2.6.0-1 How reproducible: Always. Steps to Reproduce: 1. yum update 2. 3. Actual results: Loading "installonlyn" plugin Setting up Update Process Setting up repositories core [1/4] Cannot find a valid baseurl for repo: core Error: Cannot find a valid baseurl for repo: core Expected results: Connection to repositories... Additional info: This is happening on a system upgraded from FC4 using the DVD image. The "funny" thing is that 2 other upgraded systems, and one fresh install works fine; and all the config files look the same to me... SELINUX=permissive SELINUXTYPE=targeted SETLOCALDEFS=0 === Contents of /etc/yum.conf [main] cachedir=/var/cache/yum keepcache=0 debuglevel=2 logfile=/var/log/yum.log pkgpolicy=newest distroverpkg=fedora-release tolerant=1 exactarch=1 obsoletes=1 gpgcheck=1 plugins=1 metadata_expire=1800 http_caching=packages === Contents of /etc/yum.repos.d/fedora-core.repo [core] name=Fedora Core $releasever - $basearch #baseurl=http://download.fedora.redhat.com/pub/fedora/linux/core/$releasever/$basearch/os/ mirrorlist=http://fedora.redhat.com/download/mirrors/fedora-core-$releasever enabled=1 gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora file:///etc/pki/rpm-gpg/RPM-GPG-KEY [core-debuginfo] name=Fedora Core $releasever - $basearch - Debug baseurl=http://download.fedora.redhat.com/pub/fedora/linux/core/$releasever/$basearch/debug/ enabled=0 gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora file:///etc/pki/rpm-gpg/RPM-GPG-KEY [core-source] name=Fedora Core $releasever - Source baseurl=http://download.fedora.redhat.com/pub/fedora/linux/core/$releasever/source/SRPMS/ enabled=0 gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora file:///etc/pki/rpm-gpg/RPM-GPG-KEY
I have a similar problem. I found that the failures started after the updates that were available on 28 March. nscd is the only one that seemed related to this problem. Anyhow, I found that on system where yum fails, wget, using the URL from the ym.repos.d files, also fails with a "no find" on the IP address (such as "download.fedora.redhat.com"). Firefox resolves that URL, and substiuting the numeric IP also causes yum to work. Of 4 machines on the same subnetwork, 3 fail and one works after the same update set on 28 March.
One correction to my comment above: The systems were running FC4 with all current updates, not FC5. So, this bug report should also be considered for FC4. Michael
OK, let me "Me three!" on my own bug... After seeing Michael's comments, I checked on the status of my remaining FC4 system. Indeed, it displays the same problem; and it started after the updates on March 28: Packages Updated: glibc-devel.i386 2.3.6-3 mtr-gtk.i386 2:0.71-0.FC4.1 perl.i386 3:5.8.6-24 glibc-headers.i386 2.3.6-3 glibc-profile.i386 2.3.6-3 glibc-utils.i386 2.3.6-3 glibc-common.i386 2.3.6-3 glibc.i686 2.3.6-3 nscd.i386 2.3.6-3 mtr.i386 2:0.71-0.FC4.1 ... and, yeah, it's the address resolution that fails; not yum per se.
See glibc bugs 186592, and 187320 Minimum necessary modification: in /etc/nsswitch.conf change the line hosts: files nisplus dns to hosts: files dns nisplus ... and the problems go away!
You are right. Just figured that out. It is unclear how/when nsswitch.conf got changed. I am looking into that. Also, depending on configureation, hosts: files dns is safe.
This problem also comes up if you have a http_proxy defined in the environment. Even if the http_proxy host works fine with a browser. Gives a 502 error. The solution of course is to "unset http_proxy".
*** This bug has been marked as a duplicate of 186592 ***