Network Configuration Diff & Versioning - rConfig V8 Core

Configuration diffs turn raw configuration backup files into a clear record of what changed on a device, and when. After reading this page you can read a stored diff, understand how rConfig V8 Core versions each backup, and find the exact line that changed without scrolling through thousands of lines of config: added lines show in green, removed lines in red, modified sections highlighted.

Why diffs matter

Troubleshooting

Device behaviour changed overnight? Compare yesterday’s config to today’s. The diff reveals the smoking gun: a new ACL, a changed routing protocol timer, or a modified interface setting.

Change validation

After implementing a change, pull up the diff and verify it matches what you intended. No surprises.

Compliance auditing

“When did you remove that security policy?” Open the config history for that date and review the diff. The before and after state is documented alongside the configuration reports.

Learning and documentation

A new engineer asks “why is this configured this way?” Show them the diff from when it was added.

How configuration versioning works

Every time rConfig backs up a device, it evaluates the configuration and assigns it a version.

Version detection

On backup completion:

The new configuration is captured and stored as a Config record.
Exclusion rules (see Diff Exclusions) are applied to produce a cleaned copy.
A SHA1 hash is calculated from the cleaned content and saved on the record.
The hash is compared against the previous successful backup for the same device and command.
If the cleaned content is unchanged, the new record reuses the previous version number and no change record is created.
If the cleaned content changed, the version number is incremented and a change record is created storing the rendered diff between the two versions.

Version metadata stored on each config:

Version number (sequential: v1, v2, v3…)
latest_version flag marking the most recent successful backup per device + command
Config hash (of the cleaned content) for integrity and change detection
Timestamp and file size

Storage behaviour

rConfig V8 Core stores every successful backup as a separate file, so you always have a complete, independently retrievable history. Version numbers only advance when the configuration actually changes (after exclusions), so a device backed up daily for a month that never changes stays at the same version number across those backups, while the most recent backup is always flagged as the latest.

Storage structure:

/storage/app/rconfig/data/
  └── Routers/
      └── router-hq-01/
          └── 2026/
              └── Jun/
                  └── 01/
                      └── show-running-config_143022.txt
                  └── 02/
                      └── show-running-config_080515.txt

Viewing configuration diffs

rConfig V8 Core provides two ways to view configuration differences.

Per-device config history

Use case: Track how a specific command’s output evolved over time for a single device, and see exactly what changed at each version.

Access: Navigate to Devices → [Device Name] → Config, then open the History panel. You can also reach a config directly from Config Tools → Configurations.

Features:

Browse the full version history for a device and command
Open any version to view its configuration
Click View Changes on a version to see the stored diff against the previous version, in both inline and side-by-side (Monaco) views
See the comparison settings and exclusion rules that were applied when the diff was generated

Manual config compare

Use case: Ad-hoc comparison of any two configuration files, regardless of device or timing.

Access: Navigate to Config Tools → Config Compare.

Best for: Troubleshooting, one-off comparisons, comparing a golden config against production.

Learn more about the Config Compare tool

Advanced diff features

Monaco editor integration

rConfig uses the Monaco Editor (the engine that powers VS Code) for diff display:

Syntax highlighting
Inline diff view or side-by-side view (toggle)
Minimap for quick navigation in large configs
Collapsible unchanged sections
Line numbers with change indicators
Copy or download either side independently

Email notifications

When a configuration change is detected, rConfig V8 Core can email the change to anyone who has opted in. Users enable Configuration Changed email alerts in their notification preferences. When a real change is recorded, an email is sent summarising the device, command, and new version, with a link to review the full diff. If no one has opted in, no email is sent.

Diff colour coding

Green: Lines added in the newer version
Red: Lines removed from the older version
Yellow/Orange: Lines modified (content changed)
Gray: Unchanged sections (collapsed by default)

Best practices

Regular backups enable better diffs

The more frequently you back up, the more granular your diffs. Daily backups mean each diff shows one day’s changes.

Tune exclusions to remove noise

Timestamps, uptime counters, and session IDs change on every backup. Configure diff exclusions so these never register as a change.

Keep a useful history window

Retain enough configuration versions online to cover your audit and rollback needs, and use configuration search to find specific configs quickly.