Hi, On Mon, Jun 07, 2021 at 09:14:13AM +0200, Dominik Csapak wrote: > On 6/7/21 08:57, aderumier@odiso.com wrote: > > Le vendredi 04 juin 2021 à 15:23 +0200, Dominik Csapak a écrit : > > > On 6/4/21 04:47, aderumier@odiso.com  wrote: > > > > I was doing a training week with students, > > > > > > > > and I see that the new ceph wizard to create pool don't allow to set > > > > min_size=1 anymore. > > > > > > > > It's currently displaying a warning "min_size <= size/2 can lead to > > > > data loss, incomplete PGs or unfound objects", > > > > > > > > that's ok  ,  but It's also blocking the validation button. > > > > > > > > > > yes, in our experience, setting min_size to 1 is always a bad idea > > > and most likely not what you want > > > > > > what is possible though is to either create the pool on the cli, > > > or changing the min_size after creation to 1 (this is not blocked) > > > > > yes, Sute. I could be great to be able to change size/min_size from the > > gui too. > > > > > > this should already possible in current versions, but as i said > not for pool creation, only afterwards > In my opinion, setting min_size below 2 and size below 3 shouldn't be possible at all. Both shouldn't be done unless you really know what you're doing. At that point, you know enough about Ceph to just type that one command. That has nothing to do with an easy and safe Ceph setup and the possibility in itself might lead to unseafe setups by users without enough knowlege about Ceph. Maybe a strong opinion, but --yes-i-really-mean-it Max