Cannot find a valid baseurl for repo: core

Jack Byers     byersj@xxxxxxxxxxx
root@bootp yum.repos.d]# uname -a

hitting this error  on  yum commands that worked  only a week or so ago

root@bootp byers]# yum provides lsusb
Loading "installonlyn" plugin
Searching Packages:
Setting up repositories
core                                                                 [1/3]
Cannot find a valid baseurl for repo: core
Error: Cannot find a valid baseurl for repo: core
[root@bootp byers]#

similarly
[root@bootp byers]# yum update
Loading "installonlyn" plugin
Setting up Update Process
Setting up repositories
core                                                                 [1/3]
Cannot find a valid baseurl for repo: core
Error: Cannot find a valid baseurl for repo: core
[root@bootp byers]#

upon googling I found a "suggestion" that
uncommenting the  "baseurl ...." line in the various
repos.d files  might help, but without explanation.

uncommenting the baseurl line   in  -core, -updates, -extras
then  allowed the "yum provides  lsusb"  to work as previously:
All three were necessary.


[root@bootp yum.repos.d]# yum provides lsusb
Loading "installonlyn" plugin
Searching Packages:
Setting up repositories
core                                                                 [1/3]
updates                                                              [2/3]
extras                                                               [3/3]
Reading repository metadata in from local files
Importing additional filelist information

usbutils.i386                            0.71-2               core
Matched from:
/sbin/lsusb
/usr/share/man/man8/lsusb.8.gz

usbutils.i386                            0.71-2               installed
Matched from:
/sbin/lsusb
/usr/share/man/man8/lsusb.8.gz
[root@bootp yum.repos.d]#


I have still not changed -development, -extras-development, updates-testing
I would appreciate some feedback on this behavior,
especiallly before I go much further and really mess up my system.

--is it now required that these baseurl lines be uncommented?

Jack

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