yum update error failed to retrieve repodata/filelists.xml.gz from ol6_x86_64_latest

When performing an update through yum I received the following error. The error was still present after trying both suggested work arounds. Yum uses a cache to speed operations and this cache can become corrupt […]

ORA-12514 TNS:listener does not currently know of service requested in connect descriptor

Connectivity errors are common questions on Oracle related forums and in many cases they are highly misunderstood by the poster of the questions and some responders. Many times the source of confusion lies in the […]

ORA-12543: TNS:destination host unreachable

Connectivity errors are common questions on Oracle related forums and in many cases they are highly misunderstood by the poster of the questions and some responders. This aim of this document is to show a […]

ORA-12545: Connect failed because target host or object does not exist

Connectivity errors are common questions on Oracle related forums and in many cases they are highly misunderstood by the poster of the questions and some responders. This aim of this document is to show a […]

NI cryptographic checksum mismatch error: 12599

In testing of Oracle Enterprise Manager 11g R1 Grid Control we noticed frequent ORA-12599 errors in the alert logs of the monitored databases including the repository database. Upon further investigation we found that the ORA-12599 […]

Using the OERR Utility to Aid in Error Investigation

Many Oracle products on UNIX have a utility called OERR that can be used to aid error investigation. The OERR utility is not documented so many new to Oracle on UNIX may not be aware […]

Metric Collection Error after fresh install of Oracle Enterprise Manager 11gR1 Grid Control

Scenario: You have completed the install of Oracle Enterprise Manager 11gR1 Grid Control and noticed the that repository database has a status with Metric Collection Error.