my new UPS: APC BE700G-GR

• en.wikipedia.org/wiki/Uninterruptible_power_supply
• de.wikipedia.org/wiki/Unterbrechungsfreie_Stromversorgung
• www.apc.com/products/resource/include/techspec_index.cfm?base_sku=BE700G-GR
• www.conrad.de/ce/de/product/973577/APC-Back-UPS-BE700G-USV-700-VA – I purchased it in their Berlin-Schöneberg store [link]

• Now my Synology DS213+ (NAS) gets its power from the UPS, and the UPS also controls USB-wise, when the NAS goes to "Safe Mode". For the USB-connected NAS, this is "local UPS support". This Synology device is now the "Synology UPS server", that controls, the remaining Synology DiskStations powered by the UPS.
• My Synology DS112+ (NAS) uses the DS213+ as "Synology UPS server".

It feels well, to have your NAS-s powered by your UPS.

UPS on the Synology wiki

User Reported Compatible Uninterruptible Power Supplies - SynologyWiki

my new file server

Producers

• synology.com (preferred)
• qnap
• drobo (good, but too expensive)

They all offer some kind of flexible disk mirroring with non-identical disks resp. disk sizes.

Main criteria:

• mini tower, not rack
• …

My colleague's good advice: Use Samsung disks!

Apparently "they all" have hardware compatibility lists, i.e. they don't work with every disk.

I think, it will be this one: Synology Diskstation DS213+ NAS System 6TB (2x 3TB WD Red für NAS WD30EFRX). This is the one I got today.