Comment 4 for bug 1644318

In case of using Ceph for volumes and ephemeral storage instances can cause resource allocation fail under heavy load. Instance will open different connection to all OSDs across Ceph cluster where parts of the it's volumes placed.
You are able to attach 10-20 volumes to 1 instance, format it and mount. But when you will try to save a lot of data to all attached volumes at the same time you will reach Max open files limits.