So I tried to update my ClearOS 7 box the other day and ran into a shit ton of issues. Apparently the system had not been updating itself for quit a while and I hadn’t noticed. Skipping the GUI I went strait to my OSX terminal to use SSH. yum update got me the original multilib problem to display itself:

libldb-1.1.25-1.el7_2.i686 != libldb-1.1.25-1.el7_2.x86_64

After a bit of Googling the horrible ClearOS forums I found enough info to get going. I did not have the same problems that the OP had but I found the info on this page to be of great help, it is what enabled me to finally get to the state to update my system (or at least uncovered other issues I needed to fix):
https://www.clearos.com/clearfoundation/social/community/repositories-404-error/latest

From what I gathered there are so many things that need to be updated there is a dependency snafu. So we have to ignore all the updates to those apps until the dependencies can be met then we can go back and update those other guys, no man left behind.

yum --exclude samba*,libldb*,libsmbclient,libwbclient,pyldb*,app-samba-* update

Thats the command that led me to discover my other issues, probably why the system wasn’t self updating. My /boot partition doesn’t have enough space. Well WTF ClearOS I used your fucking installer. Douche cannons. On to that later. At first yum --exclude samba*,libldb*,libsmbclient,libwbclient,pyldb* update is what they had to get going and it worked a bit but samba still was throwing errors for app-samba-blah-blah the ClearOS samba module I assume. So we had to ignore that bitch too. Samba is always a bitch no matter what system I have worked on samba always rears its head somewhere.

I COULD update, if I didn’t have the partition issue. Great no I have to expand /boot. Fuck me.