OpenStack - Swift, Ceilometer and other projects

Swift – Object Storage

Object store allows you to store or retrieve files. It provides a fully distributed, API-accessible storage platform that can be directly integrated into applications or used for backup, archiving and data retention.

Note: Object Storage is not a traditional file system, but rather a distributed storage system for static data such as virtual machine images, or photos, e-mails, backups and archives.

  • Proxy server (swift-proxy-server) accepts incoming requests, like files to upload, modifications to metadata or container creation; it also serves files and provides container listing
  • Accounts server manage accounts defined within the object storage service.
  • Container servers manage mapping of containers, folders, within the object store service.
  • Object servers manage actual objects, files, on the storage nodes.

openstack swift object storage

Also replication services run to provide consistency and availability across the cluster, audit and update.

Ceilometer - Telemetry

The required steps to bill for usage in a cloud environment are metering, rating and billing. Because the provider's requirements may be far too specific for a shared solution, rating and billing solutions cannot be designed as a common module that satisfies all possible scenarios. Providing users with measurements on cloud services is required to meet the "measured service" definition of cloud computing.

The Telemetry module was originally designed to support billing systems for OpenStack cloud resources. This project only covers the metering portion of the required processing for billing. The module collects information about the system and stores it in the form of samples in order to provide data about anything that can be billed.

openstack ceilometer telemetry

The list of metrics is continuously growing, which makes it possible to use the data collected by Telemetry for many more purposes other than billing. For example Heat can autoscale resources when Ceilometers triggers an alarm, for example adding more front-end web servers when CPU utilization is more than 70% for 5 minutes.

Other projects

Although the former ones are the most relevant, there are three other projects worth mentioning:

  • Trove is a database-as-a-service provisioning relational and non-relational database engines. It allows an agnostic access to databases, currently supports MySQL and PostgreSQL, but vendors like Oracle and Microsoft might provide a Trove plugin for their databases in future.
  • Ironic (Bare Metal Provisioning), is an incubated OpenStack project that aims to provision bare metal machines instead of virtual machines. Ironic is currently in use by HP Helion.
  • Zaqar (Multiple Tenant Cloud Messaging), is a multi-tenant cloud messaging service for Web developers. Zaqar was formerly known as Marconi.
  • Designate provides a DNS as a Service for OpenStack.

SecurePass: centralized authentication

Here’s SecurePass, a cloud-based service for multi-platform authentication based on One Time Passwords.


Password management inside a company is always one of the most delicated and debated topics, and it gets even worse as the number of employees and services to be managed grows. GARL, a Swiss company specialized in security systems, offers SecurePass, a centralized service for identity management.
This offer is composed of four different types of subscriptions that differ in the features included and, of course, the price. The entry-level offer (Personal) is free but has a maximum number of two users and only SSO authentication; as price increases, we have the Business, Enterprise+ and Service Provider plans; the details of the number of users included and the authentication modes supported are available at this link. We’d like to point out that all the prices are quite cheap (3 or 7 € at month per user).

Read more ...

Cloud Native Apps: the VMware platform

The evolution towards cloud solutions is one of the biggest revolutions in the IT sphere and it is completely changing the way of planning and evaluating infrastructures in a business setting.

It’s not a piece of news that the Infrastructure as a Service (Iaas) architectures allow system administrators to leverage the service model to consolidate servers, increase the availability of business applications and, in most cases, even to lower costs.

In the transition from virtualization to cloud, VMware has been one of the reference players for sure thanks to its advantage gained in those years when it really was the only company that invested in the development of virtual solutions. Nowadays -whatever the vendor of my hypervisor might be- virtual machines, as a matter of fact, are the fundamental computing unit of an IT system.

However, something is deeply changing in IaaS architectures: we’re talking about two important innovations such as the development of applications built natively for a cloud architecture and containers, which radically simplify the implementation and the development of the more traditional applications. VMware is naturally working as quick as possible to maintain its advantage in this sector too.
Let’s see how by analyzing the solutions introduced during the last VMworld (Europe and USA).

Anatomy of a cloud-native application

According to  Kit Colbert -VMware’s VP & CTO and Team Leader of the Cloud Native Application project- the term cloud-native is used for these last-generation applications built on top of dynamic and elastic infrastructures. Software defined datacenter, coupled with the infrastructural elements of the vSphere and NSX packages, is the ideal setting where to run traditional and cloud-native applications.

Read more ...

VPS (third part): evaluating performances

Articles of the VPS column:

This is the third part of our guide to the choice of a VPS. In the previous issues, we have talked about how to choose RAM, CPU and disk of a virtual server on which run your applications. Today we’ll dig deeper on how to actually evaluate performances

Before starting to run benchmarks on the VPS you manage, I’d like to remember that in order to have a significant value, the test must be reproducible in different hours and situations. If you have bought a VPS or have requested the provider for a testing VPS and have measured some great performances, don’t ever think that it’s enough to give a definitive evaluation.

Location and obsolescence: cloud grows old

Keep in mind also the geographic position of the VPS: if you have performed a test on the datacenter in Amsterdam, you might get different results if you run it again on a datacenter in Rome. Perhaps the machines used for trials are different from the ones used in production.

Read more ...

OpenStack - Components

Previous article: OpenStack Introduction

OpenStack is a collection of open source technologies delivering a massively scalable cloud operating system.

OpenStack cloud operating system controls large pools of compute, storage and networking resources throughout a datacenter, all managed through a dashboard that gives administrators control while empowering their users to provision resources through a web interface.

We can think of it as software to power our own Infrastructure as a Service (IaaS) offering, like the one behind Amazon Web Services.

Read more ...

OpenStack - Cloud: a planet to discover

I’ve been sitting in front of many European IT Managers and CTOs and when they want to hear from me about OpenStack or Cloud, most of the times they mean something different: customers want a VMware replacement for virtualization. The most audacious ones are willing to have a nice web interface to access their virtual machines and that’s it.

Cloud sounds like yet another marketing buzzword, it can mean just about anything or nothing at all. We are not discussing here what is the reason of walking away from VMWare, but the idea of the equation “Cloud=Virtualization” is pretty spread across all the customers. This is actually what some vendors tried to let you think of cloud.

While Cloud implies a virtualized environment, virtualization is not a cloud. Let me define Cloud using the NIST definition: “Cloud computing is a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources (ex: networks, servers, storage, applications and services) that can be rapidly provisioned and released with minimal management effort”.

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OpenStack - Introduction to OpenStack

Previous article: OpenStack: a planet to discover

The great advantage of OpenStack is that the end customer can choose whether to use the reference implementations for each project or a vendor-specific implementation for each one. The promise of OpenStack is the interoperability amongst different components from different vendors or open source projects, giving the customer the choice to find out what is the best solution for their own needs.

OpenStack could bring the following benefits to you:

Read more ...

Here's the secret to compete with AWS: interview with Ditlev Bredahl, OnApp CEO

Ditlev Bredahl, CEO OnApp

We’ve talked with Ditlev Bredahl, OnApp founder and CEO, during VMworld 2015 in Barcelona. This is what he told us.

Tell us about how the OnApp adventure began.

I founded OnApp in 2010. Before 2010, I was personally managing a Service Provider, i was providing several companies with hosting services and I decide to sell mine and dedicate to a new project. As Amazon Web Service continued to grow, I wanted to realise something that could compete with such colossus. No small cloud provider can compete with Amazon: it cannot provide the same global coverage, it’s not able to build an infrastructure that scales the same way and it can’t include in the offer all the services that Amazon proposes.

OnApp is a revolutionary service because it allows all the Service Provider of this world to ally creating a sort of federation, making a competition with Amazon possible.

Read more ...

VPS (second part): the SSD trick

Articles of the VPS column:


We now continue with our journey in the analysis of the VPS offers available on the market discussing one of the most critical aspects in the choice of a virtual machine: performances, capacity, availability and typology of storage.

The first important observation regards the data integrity guarantees that are proposed for the VPS we are about to buy. Most VPS that you’ll find on the Internet don’t offer any backup and data integrity guarantee at all. Even though this may seems crazy.
However, some solutions offer, at an additional cost, slightly better protection levels.
Unfortunately those who offer a backup solution too don’t behave always too well. The vast majority of these services - even if they charge more than 20-30% or the regular cost of the VPS just to enable the backup function - just make an image of the VM’s disk without offering any granular backup option. If, for instance, you run an Object Storage system like Owncloud on a VPS and a file, or a folder, is accidentally deleted, the only option is to restore the whole previous image, resulting in the loss of all the data modified in the last day or week (according to the backup frequency).

Obviously the only solution to this problem that can let you sleep at night is to backup data by yourself, with all the costs, burdens and memorization troubles that arise. Backup must be saved somewhere else than the disk of the VPS or a VPS on the same storage.
Be careful and do your math before coming to hurried conclusions.

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OpenStack - Regions and Availability Zones

OpenStack was made from the ground up to scale to thousands of nodes and span different datacenters and geographical regions. For this reason, Openstack clouds can be divided in three main hierarchical zones: Regions, Availability Zones and Host Aggregates.

openstack regions

Each Region has its own full Openstack deployment, including its own API endpoints, networks and compute resources. Different Regions share one set of Keystone and Horizon services, to provide access control and a Web interface.

Availability Zone
Inside a Region, compute nodes can be logically grouped into Availability Zones (AZ): when launching a new VM instance we can specify the AZ we want it instantiated in, or even a specific node inside an AZ to run the VM instance.

Host Aggregates
Besides AZs, compute nodes can also be logically grouped into Host Aggregates.
Host Aggregates have meta-data to tag groups of compute nodes, e.g. all nodes with an SSD disk can belong to one Host Aggregate, while another Host Aggregate may contain all nodes with 10 GB NICs.

One compute node can be put into both an Host Aggregate and an Availability Zone at the same time, as they do not conflict. Moreover, one compute node can belong to more than one Host Aggregate. Host Aggregates are visible only to the admin and can also be used to mix hypervisors in the same AZ, for example to save license costs: some vendors provide free guests for their hypervisors.

OpenStack Compute cells allow you to run the cloud in a distributed fashion. Hosts in a cloud are partitioned into groups called cells. Cells are configured in a tree. The top-level cell ("API cell") has a host that runs the nova-api service, but no nova-compute services.

This allows for a single API server being used to control access to multiple cloud installations. Introducing a second level of scheduling (the cell selection), in addition to the regular nova-scheduler selection of hosts, provides greater flexibility to control where virtual machines are run.

Unlike having a single API endpoint, regions have a separate API endpoint per installation, allowing for a more discrete separation. Users wanting to run instances across sites have to explicitly select a region. However, the additional complexity of running a new service is not required.

OpenStack - Nova and Glance

Nova – Compute

Probably the most known among the projects, it provides virtual servers upon demand. Nova is the most complicated and distributed component of OpenStack. A large number of processes cooperate to turn end user API requests into running virtual machines.

These are the Nova components and their functions:

  • nova-api : a RESTful API web service which accepts incoming commands to interact with the OpenStack cloud
  • nova-compute: a worker daemon which creates and terminates virtual machine instances via Hypervisor’s APIs
  • nova-scheduler: takes a request from the queue and determines which compute server host it should run on
  • nova-conductor: provides services for nova-compute, such as completing database updates and handling long-running tasks
  • nova database: stores most of the build-times and run-time states for a cloud infrastructure
  • The queue provides a central hub for passing messages between daemons. This is usually implemented with RabbitMQ
  • Nova also provides console services to allow end users to access their virtual instances console through a proxy. This involves several daemons (nova-console, nova-novncproxy and nova-consoleauth)
  • nova-network : a worker daemon very similar to nova-compute. It accepts networking tasks from the queue and then performs tasks to manipulate the network (such as setting up bridging interfaces or changing iptables rules). This functionality is being migrated to Neutron, a separate OpenStack service
  • nova-volume : Manages creation, attaching and detaching of persistent volumes to compute instances. This functionality is being migrated to Cinder, a separate OpenStack service.

openstack nova compute

Nova also interacts with many other OpenStack services: Keystone for authentication, Glance for images and Horizon for the web interface. The Glance interactions are central to OpenStack. The API process can upload and query Glance while nova-compute will download images for launching images.

Historically, most OpenStack development is done with the most community supported KVM: this allows you to refer to Internet forums to find help on your issues. All the features that are currently supported in KVM are also supported in QEMU.

Microsoft Hyper-V and VMware ESXi too are gaining much support, with Hyper-V now being available with a free license. ESXi can also be used with a free license however API support is limited to READ ONLY without vCenter or an Enterprise license.

Nova has support for XenServer and XCP through the XenAPI virt layer. Note that this does not imply support for other Xen-based platforms such as those shipped with RHEL 6 or SUSE, which is provided via the libvirt layer (i.e. Xen via libvirt).

Nova also supports bare metal provisioning through the Ironic project, that means it is possible to deploy to hardware in the same way the end user deploys virtual machines. By default, it will use PXE and IPMI in concert to provision and turn on/off machines, but Ironic also supports vendor-specific plugins which may implement additional functionality. Some vendors, most notably HP Helion, use Ironic to deploy OpenStack itself.

Glance – Image Store

It provides discovery, registration and delivery services for disk and server images.
List of components and their functions:

  • glance-api: accepts Image API calls for image discovery, image retrieval and image storage
  • glance-registry: stores, processes and retrieves metadata about images (size, type, etc.)
  • glance database: a database to store the image metadata
  • A storage repository for the actual image files. Glance supports normal filesystems, Ceph block devices, Amazon S3, HTTP and Swift.

Glance accepts API requests for images (or image metadata) from end users or Nova components, and can store its disk files in the object storage service, Swift or other storage repository.

openstack glance image store

OpenStack - Neutron and Cinder

Neutron – Network

Neutron provides “network connectivity as a service” between interface devices (e.g., vNICs) managed by other OpenStack services (e.g., Nova). The service works by allowing users to create their own networks and then attach interfaces to them. Neutron has a pluggable architecture to support many popular networking vendors and technologies.

  • neutron-server accept API requests and routes them to the correct neutron plugin
  • plugins and agents perform actual actions, like plug/unplug ports, creating networks, subnets and IP addressing
  • it also has a message queue to route info between neutron-server and various agents
  • it has a neutron database to store networking state for particular plugins

Neutron will interact mainly with Nova, where it will provide networks and connectivity for its instances.

openstack neutron network

Cinder – Block Storage

Cinder allows block devices to be exposed and connected to compute instances for expanded storage & better performance.

  • cinder-api accepts requests and routes them to cinder-volumes for action
  • cinder-volume reports reading or writing to the cinder database to maintain state, interacts with other processes (like cinder-scheduler, see below) through a message queue and directly on block storage providing hardware or software
  • cinder-scheduler picks the optimal block storage node to create the volume on
  • the messages queue routes information between Cinder processes
  • a cinder database stores volumes state

openstack cinder block storage

Like Neutron, Cinder will mainly interact with Nova, providing volumes for its instances.

Software defined datacenters according to VMware

Alberto Bullani, Country Manager VMware Italia

After last VMworld held in San Francisco, CA, on 31 August, VMware Italia has presented all the new features to the press of our country. Alberto Bullani, Country Manager, by introducing the main concepts of software defined datacenters, a topic that VMware has been harping on for years, seized the opportunity to talk about a new report concerning the employees' “digital skills”.

Read more ...

1Backup, a cloud and on-premises solutions for MSP, resellers and users

In the cloud era defining the boundaries between what remans inside the house and what goes on the Internet becomes harder and harder.
The same applies to 1Backup, a backup software that can be used within the walls on a local storage, or off-premises, in Coretech’s cloud, the company that sells it in Italy.

1Backup is a product that has two distinct utilization categories: end users seeking an easy way to backup data and system administrators, Msp and IT services retailers wanting a well localized product to offer to their clients approaching offsite backup, outside the walls.

The sotware is based on an Agent that can be donwloaded and installed on every desktop or server device, Windows (XP to 10, Server 2003 to Server 2012 R2), Linux (official support only for CentOS and Red Hat) and Mac (10.5 to 10.10), and a web interface with which other users with limited space and number of agents can be created, or even other sub-admin users capable of creating other users.
Msp, resellers and IT managers can assign permissions to clients, employee, etc.

Read more ...

VPS: the cores trick

Articles of the VPS column:

Here we are at the first first stage of our guide dedicated to the choice of a Virtual Private Server cloud service: let’s discover all the secrets of cores and vCPU.

If you’re not satisfied with the offerings from Amazon, Google and Microsoft, all you need is a couple of Google searches to find out hundreds, even thousands, of different VPS (Virtual Private Server), public cloud and other IaaS (Infrastructure as a Service) services.

Prices are extremely heterogeneous and they spread from offerings lower than 20€/yr to several thousands of euros monthly. In most cases we’re dealing with a supply of Virtual Machines based most times on Linux, and sometime even on Windows. Even if we try to define some basics requisite (RAM, disk, cores and available bandwidth), offerings vary a lot in terms of price, even though services like backup or firewall are excluded. How is it possible? Are there some obscure, hidden differences that allow us to comprehend those differences? Or do we just pay the “brand”? What kind of supporting service is available? What is the availability of the service?

Read more ...

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Issues Archive

  •  GURU advisor: issue 21 - May 2019

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    GURU advisor: issue 14 - May 2017

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