KB73,  Currently there isn't a way to individually delete a specific event within the Hardware log. This is due to the information in question residing within the ESM chip, as well as actively retrieved by OMSA. So this being said, even if you were to edit the file that OMSA creates with the ESM log in it, essentially when you restart OMSA it would rewrite any changes you made in the file, and would display the error again. The only option you have is to make a back up of the log, for "referencing" as you stated, but then just clearing the log after backing up.  Let me know if this answers your question. 
Hi everyone, our monitoring system (which pulls info from openmanage) has a critical event on it, which I know is fine, it's been dealt with. Now, I know I could clear the whole log using either the iDrac or omconfig, but I'd rather just remove this single event, leaving the other events untouched on the box. It'll be going to a syslog server in the future but at the moment it's not been configured to do so, so I'd rather not lose past events. Does anyone know a way to remove a single event or do I have no option here but to clear the whole log? Thanks.
PowerEdge R720 remove individual event