Hi.  I was getting the same error.  It seems to be related to the "Dag" repository.  (ftp://ftp.scientificlinux.org/linux/extra/dag/redhat/el4/en/$basearch/dag/.)  If I disable that, e.g. by using "--disablerepo dag" in the yum command line or simply by moving away dag.repo from /etc/yum.repos.d, the error goes away.

Anyone from the SL team know what the problem is with this repo, which is after all hosted (or at least mirrored) at scientificlinux.org?

   Cheers,
   Glenn   


-----Original Message-----
From: [log in to unmask] on behalf of Adrian Sevcenco
Sent: Sun 3/30/2008 6:33 AM
To: [log in to unmask]
Subject: yum update error SL(C) 4.6
 
Hi! I have a strange error when i do a yum update with dag repository 
enabled. the error is :
Reading repository metadata in from local files
dag       : ############################ 
5084/8828Traceback (most recent call last):
   File "/usr/bin/yum", line 29, in ?
     yummain.main(sys.argv[1:])
   File "/usr/share/yum-cli/yummain.py", line 92, in main
     result, resultmsgs = do()
   File "/usr/share/yum-cli/cli.py", line 471, in doCommands
     return self.updatePkgs()
   File "/usr/share/yum-cli/cli.py", line 949, in updatePkgs
     self.doRepoSetup()
   File "/usr/share/yum-cli/cli.py", line 75, in doRepoSetup
     self.doSackSetup(thisrepo=thisrepo)
   File "__init__.py", line 260, in doSackSetup
   File "repos.py", line 287, in populateSack
   File "sqlitecache.py", line 96, in getPrimary
   File "sqlitecache.py", line 89, in _getbase
   File "sqlitecache.py", line 359, in updateSqliteCache
   File "sqlitecache.py", line 251, in addPrimary
   File "sqlitecache.py", line 197, in insertHash
   File "sqlitecache.py", line 449, in values
   File "sqlitecache.py", line 441, in __getitem__
   File "mdparser.py", line 73, in __getitem__
KeyError: 'epoch'

Its true that this in on SLC, but i didn't think that is a difference on 
yum level so i posted here.
Thank you,
Adrian