Cloud, Cloud, Cloud. Everyone is talking about the Cloud but a lot of people are still in the fog with Cloud technologies. Let’s talk about basic features of the Oracle Cloud, called OCI for Oracle Cloud Infrastructure.
What is really OCI?
OCI is physically a lot of servers in datacenters all around the world. These servers are not very different from the servers you probably have in your own datacenter. Some of these servers are already in use by the customers, and some are immediately available for existing customers or new customers. Most of the customers will not use complete servers but part of them, thanks to the virtualization layer on OCI. A real server can hold several virtual servers, quite a lot actually. Oracle tells us that there is no overprovisionning on OCI: if you create your own server with 2 CPUs and 64GB of RAM, you’re pretty sure that these resources are available for you on the physical server, even if you don’t plan to use them at full throttle. If you need a complete physical server for yourself, it’s also possible, and it’s easy to provision just like a virtual machine.
What do I need to create a server in OCI?
OCI is actually available through a website, the OCI console, but you’ll have to buy Cloud credits to be able to create resources in this Cloud.
Two other options are available:
– ask your Oracle software provider for free trial Cloud credits for testing OCI
– create a free account and use only always-free resources (quite limitating)
When you’re connected to your brand new OCI account onto the console, just create a compute instance. A compute instance is a server for multi-purpose usage. Several options are available at server creation, like the number of CPUs, the amount of RAM, the size of the boot disk, and the OS that will come pre-installed. Provisionning a simple Linux server takes 2 minutes. Deleting a server is also a matter of minutes.
Can I go straight to server creation?
Not really. You cannot simply create a server, because you’ll need to put this server in a compartment, a kind or virtual container for your servers. So first step is to create a compartment. Compartments are fully isolated between them.
Then, you’ll need a private network (called Virtual Cloud Network or VCN) where to put your server. This private network should be created with care because it cannot overlap your on-premise network, especially if you plan to connect them (you surely need to). With network creation, other basic network components need to be also configured.
What are the basic network resources to configure?
First of all, all these resources are virtual resources in OCI. When configuring your network, you’ll also need at least one subnet from your VCN, a firewall (called security list), a router (route table) and a gateway for connecting this server (NAT gateway for outbound internet connexion or internet gateway for both inbound and outbound connexions).
Your OCI network will be linked to your on-premise network with IPSec VPN technology or FastConnect. This last option being a dedicated connexion to your existing infrastructure that does not go through internet.
So before creating your first server, you’ll need to define and configure all these network settings properly.
How to connect to this server?
If you don’t want to configure a VPN or a FastConnect link for now, you can associate your compute instance to an internet gateway to make it available from everywhere. Security is achieved with SSH keys: you provide your public key(s) on the OCI console for this server, and only you will be able to establish a connexion to your server. Later, a VPN or FastConnect configuration will let you reach all your OCI servers as if they were on your network.
What are the other services available?
If you’re thinking about OCI, it’s probably because you do not only need servers: you need Oracle databases. Actually, you don’t have to provision compute instances to install databases on it. You can directly provision databases, for various versions, Standard or Enterprise Edition, with you own license or without any license (the license fee will be billed as if it were an OCI resource – on a monthly basis). For sure, an underlying server will be provisionned, but you don’t have to create it as a separate task. If you need to connect later to this server, it’s possible as if it were a normal compute instance.
A key feature of OCI is what they call autonomous database: it’s a self-managed database that doesn’t give you access to the server or even the SYSDBA role on the database. You control this kind of DB through a dedicated interface (for loading data for example) and let Oracle automatically manage the classic DBA tasks, even those high-level. Autonomous database comes in two flavours: OLTP or Datawarehouse. Embedded autonomous engine will act differently.
Database services also come with automatic backup you can simply configure when creating the database (or after). Just define what kind of backup you need (mainly choose from various retentions and frequencies) and RMAN will automatically take care of your backups. Restore can be done directly through the OCI console.
Other services are also available, like load balancer or MySQL databases. Some services are free, some come at a cost.
How about the storage?
Multiple storage options are available for your servers depending on your needs:
– block storage: this is similar to LUNs on SAN. Choose the size at block storage creation and plug this storage to your server for a dedicated use
– file storage: this is similar to NFS. A shared storage for multiple servers
– object storage: this storage is usefull to make some files available wherever you need, just by sharing a link
Storage on OCI only relies on SSD disks, so expect high performances regarding I/Os.
How much it costs?
That’s the most difficult question, because you’ll have to define your needs, build your infrastructure on paper, then compute the cost with a cost calculator provided by Oracle. There is two billing options available at this moment: prepaid, with Universal Cloud Credits, or pay-as-you-go based on service utilization. The costs may vary depending on multiple parameters. Base budget for an OCI infrastructure starts from 1000$ a month. Don’t expect an OCI infrastructure to be much less expensive than on-premise servers: it’s mainly interesting because you don’t bother with budgeting, buying, deploying, managing servers on your own. And think about how quick you can deploy a new environment, or destroy an old one. It’s another way of spending your IT budget.
OCI is a mature Cloud, ready for production and with multiple services available and evolving constantly. Test-it to discover how powerfull it is and make sure to understand all the benefits you can get compared to on-premise solutions.