Expansion - RX418 vs RS819 Question

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Expansion - RX418 vs RS819 Question

RS1221+, RS819, RS217
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I am outgrowing my RS217 and looking it to replace it with a 4-bay. Limitations are 1U and around 30cm depth, must support BTRFS, must be UPS aware, ideally with low power consumption with CPU performance requirements at the lower end of the scale.

Two options come to mind - the RX418 & RS819 and these are two very different units.

RX418 - The good:
It is cheaper, more available, requires much less power but will be effectively 'on' standby 24/7 along with my main NAS; offers much faster file transfers between volumes and Hyper Backup tasks due to eSATA link, plus easier management through the 'single pane' of my main NAS.

RX418 - The bad:
Can only ever be an expansion unit, does not offer a virtual air-gap between Hyper Backup and Hyper Backup Vault, cannot be used as an emergency NAS should the main NAS fail.

RS819 - The good:
It is a fully-fledged NAS with all the features. Consumes more power in use but can by offset by timed wake-up events such as Hyper Backup Vault tasks. Offers a virtual air-gap between prime and backup data (segregation). Can be used as an emergency NAS should the primary NAS fail.

RS819 - The bad:
Over £100 more expensive and less retail stock around. Most of the extra features will be of no relevance when primarily used as a Hyper Backup Vault. More heat produced when in actual use. Much slower file transfers and initial backup tasks due to the 1GbE link bottleneck.

So do I go for the cheap option that locks me in to an (admittedly faster) expansion unit built for the job, or do I find the extra money for a second proper NAS with more redundancy; albeit one bottlenecked by the 1GbE link?


[I would not be in this quandary if I had not had a Synology NAS die on me recently... my next 'spare' NAS has suddenly become a prime unit again... grumble, Atom bug... grumble]
I'm aware of those who were mad enough to run a volume that straddled the eSATA cable; but they probably run with scissors too. I am a little surprised that Synology offers that function at all. Do they have weaknesses beyond that case?

Having looked further at the model history the ongoing utility of the RX units looks pretty weak, with Synology dropping them after 1 or 2 models. Makes the value proposition even more questionable.

I'm thinking that I should stick with what I know and run a primary and secondary NAS together and drop the idea of an expansion unit. It would be an easier choice if Synology stopped their death-grip on 1 GbE ports.

The RS819 units are out of stock in the usual places so perhaps an update is inbound. There is an RS821 mentioned in one of the Synology PCIe support documents too.
Using a DS unit for off-site was great until it died on me during a pandemic travel ban. If you asked me back then if a possible future pandemic was part of my backup strategy I would have laughed out loud.

I do intend to use my DS1517+ for off-site use when I can but I like to have a robust on-site backup and local archive. At some point I may have to look at cloud storage (shudder) as I am slowly running out of relatives & locations where I can park a remote NAS.

I have shelved the idea of buying an expansion unit and just looking for a 4-bay 1U NAS for on-site use.
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To close this thread out I took the advice and went with an RS819 4-bay NAS, which is up-and-running in my rack:


Pretty happy with it so far. Nice and quiet too.

Appreciating the extra bays for sure and the CPU is better than expected.

Having had the RS819 running for a while I should look at 'cleansing' the RS217 and selling it somewhere. After the testing-times of the Atom bug it is nice to still have a fully working NAS at the point of upgrade.

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