The GARR Cloud Platform is built on an infrastructure distributed geographically over 5 sites and implemented as a part of the GARR-X Progress project. The five data centres are located in 5 cities and interconnected with high capacity fiber links. Overall, the infrastructure boasts 8448 hyper-threaded physical cores, 66 TB RAM and 10.3 PB of disk space.
The equipment guarantees a high level of hardware reliability, thanks to the redundancy of all active and passive components.
Resources are distributed over 5 geographical locations, co-located or in the vicinity of GARR Network PoPs.
The three sites located at the GARR PoPs in Palermo, Catania and Bari host 3 racks each, while those at the PoPs in Naples and Cosenza host one each. The main sites are interconnected on a redundant fibre backbone ring, with a capacity of 40 Gbps. The others are connected to two of the main sites with 10 Gbps fiber links.
The key technical features for GARR cloud infrastructure are:
- Linux operating system for servers;
- Cloud platform based on OpenStack;
- Block and Object Storage provided through Ceph.
The platform includes global components, i.e. those managed as one entity over the whole platform, and local components, i.e. those independently managed on different sites.
- allow users to access all resources in the cloud with the same credentials;
- offer a single archive of VM images and snapshots for the whole cloud;
- offer a single object storage for the whole cloud, which is available even in case of temporary unavailability of one of the sites.
The local components, installed in all main sites, implement in each site an environment (or region, in OpenStack’s vocabulary) on which users can build their own virtual infrastructure, including
- virtual network infrastructures (routers and networks);
- tailored VMs, sized and configured as needed, that can be saved, duplicated through the snapshot tool and linked with each other and the external world through the virtual network;
- virtual volumes to be associated to VMs as block storage;
- customised access and security policies for the virtual infrastructure.
All this is controlled via a dashboard, from where users can access the different cloud regions, the object storage, and the archive of VM images.
Local components are designed to ensure service stability and continuity even in the event of failure of one of the three racks hosted in the three main sites.
The reference architecture selected for the GARR cloud is described in a declarative way and easily configured and replicated.