This article seems to take it on Redis as it unproperly supports this use case, but Redis does not seem to be a right choice for a cheap vertically scalable k-v store. I didn't know SSSD but really you could have chosen amongst many other k-v stores or even memcache with disk support.
I guess the point is that someone chose Redis and soon realized that RAM was not going to be the cheapest store for 500Gb of data. But that is not Redis' fault.
I guess the point is that someone chose Redis and soon realized that RAM was not going to be the cheapest store for 500Gb of data. But that is not Redis' fault.