lsb_release comes out of redhat-lsb-core .

Description : The Linux Standard Base (LSB) Core module support provides the
             : fundamental system interfaces, libraries, and runtime 
environment
             : upon which all conforming applications and libraries depend.

Personally, I put it on every system I manage.  But that is me, YMMV.

Based on what you've sent I think I've got it cleaned up.

Can you run:
yum --enablerepo=* clean expire-cache
yum check-update

and see if the problem is resolved?

Pat

On 01/26/2017 10:58 AM, Gilbert E. Detillieux wrote:
> Pat,
>
> I've attached two transcript files...  The first one (script.txt) is 
> from a newly set-up SL 7.2 system that I upgraded to 7.3 yesterday.  
> The other (script2.txt) is from an older system, that's gone through 
> upgrades from 7.1 to 7.2, then to 7.3, and has a more substantial set 
> of packages and repos installed.
>
> I should add that I see the error messages about the update notices 
> when I run "yum check-update", but not when I run "yum update".  (I 
> think I was seeing it on the latter command as well, at least 
> initially, but it's possible that it stopped doing that on an earlier 
> run of "yum clean all" I ran yesterday.)  I don't know if that's to be 
> expected or not.
>
> BTW, I don't seem to have the "lsb_release" command installed. Know 
> what package I might find that in?
>
> Thanks,
> Gilbert
>
> On 26/01/2017 10:22 AM, Pat Riehecky wrote:
>> Can I have you send me the output of the following:
>>
>> yum --enablerepo=* clean expire-cache
>> yum repolist
>> lsb_release -a
>> cat /etc/yum/vars/slreleasever
>> yum makecache
>> find /var/cache/yum/x86_64/ -type f -name repomd.xml -ls -exec sha1sum
>> {} \;
>>
>> Pat
>>
>>
>>
>> On 01/26/2017 10:06 AM, Gilbert E. Detillieux wrote:
>>> Pat, I'm seeing these same errors, even after a "yum clean all".  This
>>> is just since yesterday's upgrade from SL 7.2 to 7.3, on many boxes.
>>>
>>> Gilbert
>>>
>>> On 26/01/2017 8:39 AM, Pat Riehecky wrote:
>>>> Hello,
>>>>
>>>> Can I have you run a
>>>>
>>>> yum clean all
>>>>
>>>> and see if the problem persists?
>>>>
>>>> Pat
>>>>
>>>> On 01/26/2017 01:12 AM, Maarten wrote:
>>>>> What do these messages mean? It says to contact the repo owner?
>>>>>
>>>>> etc/cron.daily/0yum-daily.cron:
>>>>>
>>>>> Not using downloaded repomd.xml because it is older than what we 
>>>>> have:
>>>>>   Current   : Wed Jan 25 20:54:42 2017
>>>>>   Downloaded: Wed Jan 25 20:54:25 2017
>>>>> Update notice SLBA-2015:2562-1 (from sl-security) is broken, or a bad
>>>>> duplicate, skipping.
>>>>> You should report this problem to the owner of the sl-security
>>>>> repository.
>>>>> Update notice SLBA-2016:1445-1 (from sl-security) is broken, or a bad
>>>>> duplicate, skipping.
>>>>> Update notice SLBA-2016:1526-1 (from sl-security) is broken, or a bad
>>>>> duplicate, skipping.
> ...
>>>>> Update notice SLSA-2017:0021-1 (from sl-security) is broken, or a bad
>>>>> duplicate, skipping.
>