[SOLVED] cluster network and storage network

[kenyoukenme]

hi everyone!

We are migrating our server to a different cloud provider.
While reading a documentation, i read this: "Storage communication should never be on the same network as corosync!".
Our server must have HA and data redundancy/ data high availability (using ceph).
The problem is, our new cloud provider only provides 1 nic on the private network but we need at least two nics (for the storage and cluster) to achieve that setup.
My question is, why is it not advisable to have the cluster and storage network on the same network (is it a bandwidth issue, latency, interference) and if there is a possible workaround for the issue.

i would greatly appreciate any answer and advice
any link, documentation or technical explanation is always welcome

thanks!

 

[LnxBil]

My question is, why is it not advisable to have the cluster and storage network on the same network (is it a bandwidth issue, latency, interference) and if there is a possible workaround for the issue.

Throughput and high availability. If your storage saturates your nic and cluster communication is delayed, your nodes may be fenced.

If cannot have real HA if you have not at least all connections two times with two switches, so you actually need 4 or at best 6 NICs. It would work with 4x 1 GBE and 2x 10 GBE for Cepth.