About this tool
Configuration reviews are easier when you can see exactly what changed. A line-by-line diff highlights additions and removals so reviewers can focus on intended changes instead of rereading two full files.
This tool compares two text configurations in the browser workflow and marks changed lines. It is useful for pre/post checks, peer review and documenting a rollback plan.
How to use it
- Paste the baseline configuration in the first field.
- Paste the proposed or post-change configuration in the second field.
- Compare the highlighted additions and removals and verify that every difference is intentional.
Example: interface description and address change
If the original interface has one description and IP address and the proposed version changes both, the diff should show the old lines as removed and the new lines as added. Unexpected neighboring changes are a reason to stop and investigate.
Engineering notes
- A text diff does not understand vendor semantics. Two configurations can be functionally equivalent even when lines differ, and order can matter differently by platform.
- Never paste secrets, SNMP communities, passwords, private keys or customer-sensitive data into any public web service. Sanitize configs first.
Frequently asked questions
Does this tool connect to my devices?
No. It compares only the text you submit to the site.
Can a clean diff prove the change is safe?
No. It proves only what text changed. You still need design review, syntax validation, dependency checks and operational testing.
Should I include the entire running configuration?
Only if needed and only after removing sensitive information. Smaller relevant sections are often easier to review.