Can I use mismatched SSDs in a Synology DS920+ for read/write cache?

[Avendor7]

Hey everyone.

Like the title says, can it be done? I recently got a DS920+ and I have one SSD installed as a cache but wouldn’t mind getting another at some point for the read/write caching. Problem is I have a Corsair MP500 480GB drive which isn’t available anymore. Would I be able to get something like a WD Blue 500GB drive and use that as the second drive? I assume it would work and just use the smallest drive size (480GB) but I wasn’t sure if Synology has some limitation in their software that would prevent it.

Thanks!

[Dutch_Master]

The most likely scenario would be that the OS will only use part of the larger drive and leave the remainder untouched. But why use a 2nd cache drive in the first place?

[Avendor7]

Synology will only enable read and write on a RAID 1 array so with my current setup of a single SSD I’m limited to read only caching.

[Buffy]

AFAIK, they should be the same, but you can try it and see for sure. Also, cache gets lots of read/write, so a cheap SSD won’t last as long I think.