Which type of backup involves saving only the SRAM data?

Saving only the SRAM data specifically pertains to the file backup method. This type of backup focuses on capturing a specific set of data, such as parameter files and other essential configurations stored in the SRAM (Static Random-Access Memory), without encapsulating the entire system state or all files, as would be the case in a complete backup.

In contrast, an image backup would include a complete snapshot of the entire storage system, capturing all data and files, not just the SRAM data. A complete backup also encompasses all files and system states, while incremental backups focus on saving changes made since the last backup, again not isolating solely the SRAM data. This clarification underscores the characteristics unique to file backups, which aim to efficiently secure particular, critical information rather than the entire system or all incremental changes.