RNas Ultra 4 Plus -- ?TLER or no

The handling of drives that don't support TLER works well with all of the applicable WD drives on the Hard Disk HCL. A drive does not get on the compatibility list without first passing extensive testing by NetGear to verify compatibility. Having said this there may be separate compatibility issues that mean that it's incompatible with firmware released before the drive was added to the compatibility list. So best to update to the latest firmware (need at least one disk installed to do this), then power down, insert rest of the disks and do a factory default (wipes all data, settings, everything via the boot menu: http://www.readynas.com/kb/faq/boot/how_do_i_use_the_boot_menu). A clean setup on the latest firmware is recommended for all new setups.

Having said this enterprise disks still do have their benefits and are designed with RAID use in mind. They should be more reliable especially in RAID arrays, have longer MTBF (Mean Time Between Failures) etc. You get what you pay for. As a home user I personally don't use enterprise disks, but in a business I would want to use enterprise disks for mission critical systems. Whichever drive you choose it can fail, so please remember that if data is primarily stored on the NAS whatever RAID you use, it is not backed up. Don't get me wrong. RAID is great and provides redundancy/high availability (except for RAID-0 which has no redundancy) reducing the likelihood of needing to restore from backup, but it doesn't replace the need for a backup. Please backup important data primarily stored on the ReadyNAS regularly e.g. to a USB disk, another NAS, the cloud, or some place else. See Preventing Catastrophic Data Loss

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