Synology Forum

You problably bought the wrong type of fan.
I'm not sure if it's the same also for your NAS, but often Synology uses the "locked rotor" type instead of the (more common) with "tachometer signal"
The two types work in a completely differrent way.

Nope. You cannot reduce the amount of disks in a RAID system.
If you replace the disks and you stop providing the 5th one, you will leave the volume in a degraded state (i.e. without redundancy)

Mainly, CPU and disks will be busy running the scrubbing operation, so other accesses to the NAS may be slow.
It depends case by case (which is why the default speed is so low), so you have to judge yourself if it's acceptable in your situation.

Note that you cannot add to a SHR volume disks smaller than what you already have in the volume, so DON'T start your SHR with the 8TB unless you plan to have only 8TB (or bigger)

I don't know exactly how the DSM is handling the case, but it could be there is some issue when adding a 3TB disk (which requires GPT partitioning) next to a 2TB one that still uses MBR, especially in regards to having the two first partitions (=system) exactly aligned for mirroring.

RAID 1 is in practice equivalent to SHR, especially on a 2-bay unit. Their is no 'RAID Basic'. You can start with one disk in 'Basic' mode and when you add a second disk expand to a RAID 1 to get a mirrored configuration Or you can start with one disk in 'SHR without data protection of fault toleran...

Marvell Armada 370 (ARMv7) @1.2 GHz
512MB of RAM, directly soldered on the mainboard

To change behaviour you need to go down with the CLI, and e.g. if your version of DSM use syslog-ng, reconfigure the file /etc/syslog-ng/syslog-ng,conf.
Happy hacking!

I don't knoiw whether things have changed in latest versions, but for a long time DSM retained its heritage of being designed for tiny boxes with small disks, and so systlog was configured to suppress most of its output. Reducing syslog output has been also a necessary measure in order to help hiber...

Update: we've formatted the four HDD and setup new partitions, but are still unable to access the NAS from the router. At this point, we're concluding that the UTP-interface of the NAS is probably broken. When the NAS boots up (even without disks), one the first it does it to initialize the NIC and...

You cannot because not even DSM knows about it.
DSM just tells to the disk subsystem 'write this data'. If the disk driver that is configured in a RAID 1 mirror doesn't return error it means it's doing its job i.e. it was successfully able to write both copies of the data.

At least theoretically, RAID 0 can be faster than Synology-JBOD, as in RAID 0 data are striped and so they are read/written on parallel disks. JBOD for Synology is a concatenation of disks so only one disk is accessed at a single time. The different structure also explains why one cannot be expanded...

the DS firmware/OS is stored on a volume, (assumedly disk 1 of multi-disk volumes Nope. Most of the DSM is stored on *every* disk in use in the system (i.e. any healthy disk, except those still marked as Non-Initialized), and a small part on an internal flash memory on board ot the NAS. That part r...

Does SHR have the same limitation? If I suffered a similar failure on a Synology with SHR, would I be stuck behind another proprietary wall, or is the SHR format documented enough that tools exists that could allow me to fix the source of corruption to get the device into (at least) a read only sta...

Probably the most you can is: - plug one 6TB to the last empty bay, make a new volume out of it - from diskstation, one by one select the folders on the old disks and set them to move to the new volume - if you have apps installed, you probably have to remove them and install them again on the new v...