So, a client’s OEM Information Report was running and email being sent, but all queries (Report sections) resulting on error:
Unexpected error getting the HTTP response stream while generating report: oracle.sysman.eml.ip.publishJob.HttpConnectionException:Response code:404
I had a silar issue, as per documented on this post: OEM Information Reports: ORA-00600 [kpndbcon-svchpnotNULL]
This is happening due TCP timeout while executing Report after 5 minutes. By default, Idle Timeout set for Profile parameter (TCP) for the virtual server in F5 is 300 seconds, for example.
I simulated manually execution of each SQL on report and noticed report takes around 8 minutes to run.
What I did? I took some of the slow queries and transformed to a Materialized View with daily refresh.
This was valid in my case because the report runs only once a day. Remember to always check on your own situation. Perhaps an hourly refresh or so is better for you.
Another possibility is to engage the LB admin to modify this parameter by setting a new protocol profile for the virtual server or modifying the existing one.
NOTE: After modifying SLB Values, you may need to restart OMS :
emctl stop oms -all emctl start oms
MOS oracle.sysman.eml.ip.publishJob.HttpConnectionException:Response code:404″ Errors for reports run from EM (Doc ID 2061361.1)