Retention

You download a 40 GB release, it hits 97% and stops. The status sits on “repairing” for ten minutes and then spits out a file that will not extract. If you have used Usenet for more than a week, you have met PAR2 — even if you have never consciously thought about it. This guide is the explainer most Usenet sites never write: what PAR2 recovery files actually are, how a repair works under the hood, why a file fails despite your provider’s giant retention number, and the settings in SABnzbd and NZBGet that decide whether a download lands clean or dies at the finish line. ...

Every Usenet provider brags about retention. “5,000 days!” “6,000 days!” Bigger must be better, right? Not necessarily. Retention is the most misused number in the entire industry, and it’s the one most likely to make you overpay. But there’s a second, quieter piece of the puzzle that almost nobody explains: PAR2 repair science. Retention is the window in which content exists; PAR2 is what actually rescues you when content inside that window is incomplete. This guide covers both — why the headline retention number misleads you, and why your downloader’s ability to repair a broken file often matters more than a couple of extra thousand days of storage. ...