DL4100 Not Booting


This morning around 1am according to some logs and such I have my DL4100 NAS stopped working. Odd.
I checked the unit out, and the LCD screen was locked up displaying the NAS’s name. No disk activity, all 4 LEDs are solid lit up for disks nut they were not actively doing anything. I power off the unit, power it on, and it won’t boot.

I’m met with a blinking blue light, with 4 disk lights solid. Nothing on the LCD screen. After about 3-4 minutes, the device reboots and does it again on a endless loop.

I tried both the 4-second, and 40-second reset procedure, no joy. I found it odd the unit didnt even reset after releasing the pin after 40 seconds or so. No response at all.

LUCKILY I happen to have a spare system available with 4 Sata ports, and enough ports to power them. I hooked the drives up and live booted PartedMagic Linux Distro ($11 https://partedmagic.com/) that I use for other things… low and behold, it supports mdadm linux volume management out of the box. The DL4100 uses a standard linux RAID5 software array and EXT4 file system.

The odd thing the SDx2 partitions which contain the data, when i do mdadm–examine /dev/sdx2 it shows all 4 volumes in good health, no issues. /dev/sdx1 appears to be a Swap partition, and /dev/sdx1 appears to be the file system for the DL4100 config. When I ran mdadm on it, it could not find any magicblocks and the filesystems would not mount. It seems somehow the DL4100’s data partition(s) got screwed up for the system itself and is preventing it from even booting or able to do a config reset as I tried.

Right now I’m going through a 20+ hour process where I managed to mount the filesystem of the RAID5 data array onto a system and I am copying over about 7TB of data to a single USB hard drive. Once that is complete it seems my next choice is zero and wipe all my drives and restart from the ground up. Hoping this info at least helps others recover their data.

Has anyone else encountered this problem? I had a power outage about a week ago, I have it on a UPS connected to it via USB, and it auto-shutdown as far as I can tell. (I was not home at the time). I logged in after I booted it back up and saw it had Battery Critically low messages and I assumed it shut off. But apart from that I have had no issues at all.


To add to this, I have checked the AC Adapter, voltage is fine. Likewise I swapped out the DDR3L memory module with two other known good ones. I popped in blank drives as well and it failed to initialize or do anything. Seems my board is shot. Given I bought it 6/2015, my 3 year warranty just ran out. Go figure…

At least data recovery was easy… kinda.

Synology DS918+ it is…


G’day, have exactly the same issue as you and I’m about to have a crack at your recovery method. Although I’m probably a little over my head…