Forums

Home / Forums

You need to log in to create posts and topics. Login · Register

Monitor change and possible bottlenecks

Good morning, I'm going to install a new Petasan cluster and I would like to ask some clarifications about monitors:

  1. Once I setup the cluster and define which are the 3 monitors (3 of the 4 data nodes), then will I be able to replace one of them in the future (let's say add a new server and make this new one a monitor removing one from the original three) ?
  2. If this new monitor is not a high-end server, with less powerful CPU, less RAM and 1 Gb/s ethernet, can this create a bottleneck in the cluster, compared to the situation where all the monitors are also storage nodes (Xeon  CPU, lots of RAM and 10 Gb/s ethernet) ?
  3. In general: would the choice of having a simple dedicated monitor (in total 1 monitor + 2 storage/monitor + 2 storage only) bring some advantage in terms of performance  and reliability of the cluster (compared to 3 storage/monitor + 1 storage only), or it would have no effects at all, or even be worse ?

Thanks for any explaination and bye, S.

You can replace the management nodes, when you deploy a node choose "Replace Management Node". It needs to have the same hostname and ip address.

You can have these nodes without storage, but they should not be underpowered, beside the Ceph monitors the management nodes also acts as Ceph mgr, mds, Consul servers, Gluster servers, Stats servers. Ceph monitors also can get quite busy in case a large cluster is recovering as they need to issue cluster maps.