Just for my amateur understanding:
Thank you for your hints and comments
A mSATA SSD will fit and work.
A 2.5in HDD/SSD may be possible. A passive adapter for mSATA to SATA and drilling a few holes in the case for the screws may be enough. Getting the power from the board is possible but may require soldering.
This list seems a bit outdated. Samsung has the 850 series and others also have newer models.
Get a Samsung 840/850 EVO with at least 250GB. Always leave free space on the drive.
There are enough people out there to find the bugs and problems and a solution.
Find an adapter to connect it to a SATA port in your PC. Adapter for your PC is for updating the SSD firmware. There is a known bug in older firmware causing unreadable data after a while.
Speed does not matter that much. You still want to move the data over network so no need for 500MB/s write speed.
Power consumption is a point that should be taken into account. Samsung ones seem to run cooler than my Marvell-chipset-based Toshiba and Crucial/Micron ones. Without active powermanagement mine get hot and start to limit their speed.
I would avoid anything smaller than 240GB as most have not enough used nand channels to work constantly fast. This may put these nice 500MB/s write speed down to 50 or even slower.
There are other interesting points like how power loss is handled and even inner workings of the nand controller like compression and even firmware differences between different manufacturers of SSDs using the same chipset.
Thanks a lot for your detailed answer.
So far looking, at a review of Samsung 840 EVO mSATA SSD Review – 1TB mSATA SSD and the fact sheets of 850 EVO mSata SSD, the follow-up series, Samsung looks quite promising in theory. Have to look for some more reports or feedbacks.
Hopefully all features, e.g. “Dynamic Thermal Guard” what might be important as the mSATA SSD will run inside the Turris Omnia box, work out-of-the-box with the router OS.
Anyhow, no stress and hurry, as delivery will still take some time.
In a previous post in Indiegogo, they announced extra pins for powering devices.
That may go together with a PCIe sata controller.
Hello adminX, think twice before getting Samsung 8XX EVO drives for Linux. They have an issue with NCQ TRIM under Linux, resulting in data loss and therefore it is blacklisted for these drives in kernel. IOW, they will never trim asynchronously under Linux, resulting in performance loss (better than data loss, though ;)).
The Samsung drives are available for a great price, unfortunately, this problem puts them in disadvantage.
there was a bug in the raid-code involved, that actualled lead to this data los, wasn’t it?.. it got fixed by samsung, but unqueued trim is still blacklisted for those drives (for some Crucial models as well)
But i can’t find any data how this affects the performance… anyone?
Trim-in-RAID was a separate bug, it was fixed last July. The NCQ TRIM is still not fixed.
Ouch… I was about to by me exactly those! Thanks for the heads-up guys!
@johndoe any recommendations on other (M)SATA SSDs (based on quality*size/price ratio)?
@woostling: that’s a good question. In places where 2.5" fits, I just use Intel. For mSata, the situation is different, as the last one from Intel was 525, 3 years ago.
The thing with the EVO is, that it can do only normal trim, which means stop the world (no reading or writing during trimming, which can take several seconds), leading to unexpected pauses during I/O. On the other hand, it should not be critical in a router. Even Windows does only this kind of trim and nobody is bothered by that.
The alternative that I’m looking at is Crucial MX200, which is about the same price, but is slightly slower (and MLC). Now if there was a way to quantify the advantages and disadvantages of both and objectively compare them…
For currently blacklisted drives see https://github.com/torvalds/linux/blob/master/drivers/ata/libata-core.c, search for “devices that don’t properly handle queued TRIM commands”.
This is what i meant with:
Even if the solution is a small speed penalty caused by not supporting Queued TRIM and other workarounds (forcibly enabling power management). My m550 is also blacklisted and i did not notice any slowdown or problem with this.
Another question: does anyone plan to use OPAL encryption on his/her SSD? if i understand this correctly, there’s only one tool for that purpose called sedutil (https://github.com/Drive-Trust-Alliance/sedutil), right? i’ve managed to crosscompile it (but gave away my WRT1200AC, so can’t test it for now)…
I’d be really happy if you (the nic.cz guys) could package it 
This tool will not be needed. It is required for TCG OPAL compliant drives to set the keys during boot. It uses a small unencrypted space of the drive. sedutil is for booting PCs. It is not needed for full disk encryption in the drive. Plain hdparm setting the key should be enough for most SSD.
[quote=“adminX, post:32, topic:101, full:true”]
This tool will not be needed. It is required for TCG OPAL compliant drives to set the keys during boot. It uses a small unencrypted space of the drive. sedutil is for booting PCs.[/quote]
there’s also a sedutil-cli tool, you can use it like hdparm to unlock a drive after the system is booted
[quote=“adminX, post:32, topic:101, full:true”]
Plain hdparm setting the key should be enough for most SSD.[/quote]
Well, some people say it’s enough to set the security password, to enable encryption on SED SSDs, others say it won’t… but nobody knows for sure and it’s also unknown where the password is stored, how it’s implemented by the different vendors, and so on… i personally won’t trust in that.
Hi guy, first of all.
Anybody interested message me.
What I am not sure about is weather the heat from the HDD will be a problem or not for the design.
Hi, I would be interested. Post the drawing picture and real one when available to get inspired…
