For a simple use case this is not an issue. - you add your ssh public key to the hosting provider, so any new VM will have it automatically - you use the snap

For a simple use case this is not an issue. - you add your ssh public key to the hosting provider, so any new VM will have it automatically - you use the snapshot service of your hosting provider for backups. If you have a database, run a cronjob that dumps it so it's in the snapshots as well. Alternatively use any backup tool to backup files to somewhere else - you do not need a separate network for simple use cases. Just encrypt traffic if you have multiple servers, odds are you only have one here anyway.