How would you deploy 5 Node Ceph over three rooms?

[jsterr]

Is a 4:2 pool setup with 3 rooms correct?

room1: server 1 and server 2
room2: server 3 and server 4
room3: server 5

• how much mons do I need here, 5?
• Is this setup correct so I can loose 2 servers anytime at the same time without having downtime?

 

[ph0x]

What do you mean with rooms? Different datacenters or just another room at home for different failure domains?
The more mons you have, the more can be offline without interrupting the cluster. More than half the number has to be online, so with five mons two can be offline.

 

[jsterr]

What do you mean with rooms? Different datacenters or just another room at home for different failure domains?
The more mons you have, the more can be offline without interrupting the cluster. More than half the number has to be online, so with five mons two can be offline.

different server rooms in different fire sections

 

[ph0x]

It's important for a cluster two have a low latency connection for Corosync and Ceph as well. If that is accomplished, you can easily spread the machines in different sections. And with 5 machines in 3 sections you're all set.