Q: I noticed that not all alarm events arrive on the server via ftp.
A: I noticed now that not all alarm events arrive via ftp on the USB stick on the router, on the internal SD card, however, already.
In the network, it may happen that the FTP or email upload times out and is aborted. This is the main reason why the cameras have an SD card on which alarm recordings can be created as a backup.
The images for the FTP or email upload are sent directly from the memory of the camera and then stored on the SD card.