I got Hikvision DS-7608NI-I2/8P NVR w/ POE running on the latest firmware, 1x DS-2CD2442FWD-IW(PoE 802.3af) and 3x DS-2CD4135FWD-IZ(PoE 802.3af) on the latest firmware.
First time doing test I put everything together and managed to have all cameras working through NVR PoE ports.
Then left it to...