Synology provides a set number of for free with every device: Standard NAS (DiskStation): 2 free licenses. Network Video Recorder (NVR): 4 free licenses. Deep Learning NVR (DVA): 8 free licenses.
For users running Synology software on non-Synology hardware (XPEnology), older versions (like 7.2.2) can be patched with modified .spk files to bypass limits. synology ip camera license hack link
Beyond these, you must purchase Surveillance Device License Packs (available in 1, 4, or 8-packs). These are perpetual (lifetime) and can be migrated to new Synology hardware. The "Hack" Reality: Scripts and Patches Synology provides a set number of for free
Synology's activation servers constantly verify keys. Updates to Surveillance Station or DSM often break these hacks, potentially locking your account for 14 days or requiring a factory reset to regain functionality. Legitimate Workarounds for More Cameras For users running Synology software on non-Synology hardware