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As documented in the Backup article, if there are no changes to the config of your device, a new "backup" point is not required. In effect, this means that rather than showing you individual backups, Unimus will show you configuration points - ranges of valid configurations on your device to build a configuration timeline of the device. To be able to do this, Unimus needs to be able to figure out if there was a config change on the device. For example, if the configuration of the device contains a timestamp (Cisco IOS will show the current timestamp of when "show running-config" was executed), this needs to be ignored so this "change" in the configuration contents doesn't create a new configuration point. Unimus contains many built-in filters for such dynamic data (as mentioned in the Backup article), but you can also create your own custom filters for backup contents.
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