A) don’t buy TVs - big monitors/bfgd ir public displays B) log dns requests and IPs the tv wants to connect to. Forward that’s requests to anything in your network (often it’s just a get request or ping request to that destinations, that satisfies the tv)

There are many factors at play.

First - SD cards can’t be trusted - they’re an disposable transfer media. Depending on the quality you’re buying, they can be absolut trash. Its basically the (cheap) MMC module with convenient connectors. Good quality modules can last a long time with regular use.

One often overlook problem is with file systems. Cameras (and my other things) use the FAT Filesystem. Which has no resilience what so ever built in and tend to corrupt the Filesystem over time with use (regular formatting should mitigate that - for digital cameras, always format with the camera).

Don’t long term store data on them. Always have Backups of your Data.

As long as you treat them for what they are - an untrusted transfer medium - you won’t have unexpected problems and data loss.

Why not - I used to add my previous gaming machines to my homelab multiple times. The only problems are cheap mainboards. Lenovos Legion Rebuilds I don’t know enough about to say if their hardware is ok for that - their workstations would better be suited, I gues. But usually I’d say: why not. Just remeber to have regular backups in place, just in case

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