Viewing ASA Change Log Diffs
Clicking the blue "Diff" link in the change log opens up a side-by-side comparison of the changes in the ASA's running configuration file. You see the differences in the two versions.
In the illustration below, the "Original Configuration" is the running configuration file before a change was written to the ASA and the "Modified Configuration" column shows the running configuration file after the change was written. In this case, the Original Configuration column highlights a row in the running configuration file that actually didn't change but gives you a point of reference in the Modified Configuration column. Follow the lines across from the left to the right column and you see the addition of the HR_network object and the access rule preventing addresses in the "engineering" network to reach addresses in the "HR_network" network. Use the Previous and Next buttons to click through the changes in the file.