‐ 33 ‐EXTEND When internal HDD(s)(including E‐SATA HDD) gets full, HDD starts to overwrite andeldest data will be erased from internal HDD and saved in USB HDD at the same time.This works when owerwrite is set to “ON” in [MENU‐SETUP‐RECORD_MISC]MIRROR Same data of internal HDD will be recorded in USB HDD.INTERNAL To use this function, more 2 internal HDD must be installed. Same data is recorded topaired internal HDDs : HDD1 and HDD2, HDD3 and HDD4 works as pairs.Example) supposed HDD1, HDD2, HDD3 are installed and set as INTERNAL function,HDD1 and HDD2 record same data as RAID 1, but since there is no pair to HDD3,Data recorded to HDD3 is not mirrored to HDD2. HDD2 is not pair of HDD3.4.2.6. NETWORK4.2.6.1. Setup