Computing services are related to computational power, that is CPU, RAM and, occasionally, storage. This power is commonly represented in units named instances.
In the cloud, an instance may be either a virtual machine, a bare metal server or a container. Since in a cloud-native environment, an instance is just a small building block of an automated and scalable infrastructure, high-availability and resiliency are provided at the application logic and are no longer demanded to the underlying hypervisor or hardware infrastructure.
In other words, if your instance fails for any reason, you must have
an application or a script in place that detects this fault and trigger some healing operations talking to the cloud provider APIs.
If you are evaluating to move your legacy application to the cloud, you must first take in proper consideration the responsibility shift from hypervisor to application layer you are going to face.
Therefore, being the single instance expendable in the economy of the service availability, the storage inside the instance is defined “ephemeral”. Persistence and durability to user data is provided via external pluggable block or object storage.
As of today, EnterCloudSuite provides four instance classes or hardware flavors:
This original flavor provides 1 to 8vCPUs, 512MB up to 32GB RAM, 20GB up to 1.2TB of ephemeral SATA storage per single instance.
This flavor is maintained for legacy support only and will be dismissed soon.
The E2 flavor is the “diskless” flavor, and comes with no ephemeral storage onboard. Storage is provided on top of external block storage.
Ranges from 1 up to 16 vCPUs and from 512MB up to 100GB RAM.
This brand new flavor provides a fixed size (25GB) ephemeral storage based on SSD drives, allowing a thousand-fold more I/O operations per second (IOPS) on the drive. It ranges from 1 to 24 vCPUs and from 512MB up to 128GB RAM.
This flavor provides a fixed size (25GB) ephemeral storage based on SSD drives, allowing a thousand-fold more I/O operations per second (IOPS) on the drive. It ranges from 1 to 24 vCPUs and from 4MB up to 64GB RAM. It offers a large availability of computing resources that is suitable for dynamic workloads. It is available only in the Milan region.
Images are software templates that can be used to deploy instances. They can be either provided by the Enter Cloud Suite team or created by the user herself as point-in-time snapshots of running instances.
Snapshots are a powerful and quick tool to store pre-configured and ready-to-run instances.
Moreover, the object storage underlying the imaging engine provides a 3x replica of the image across three different regions (Milano, Frankfurt and Amsterdam), thus allowing for built-in disaster recovery and backup capabilities.
Public images include the following operating systems and software:
All instances are accessible only via a valid SSH private/public key. Windows instances may be accessed either via a direct password protected console or via private/public key exchange.
All instances can be protected by a local firewall or a perimetral one: point and click configuration is very easy and user friendly, and allows to configure general policies, protocols, ports and IPs allowed.
BGP-based Anti-DDoS (Distributed Denial of Service) is in place and protects the whole network in each region from attacks up to hundreds of Gbps.