Browsed by
Month: October 2016

What is SMI-S? What is the EMC SMI-S Provider? What is ECOM?

What is SMI-S? What is the EMC SMI-S Provider? What is ECOM?

What is SMI-S? What is the EMC SMI-S Provider?

The first step in understanding the functionality of ECOM and the EMC SMI-S Provider, is to first answer the question of what is SMI-S? Essentially it is an attempt at standardisation of storage management and it’s related technologies to increase interoperability. This standardisation was created by The Storage Networking Industry Association (SNIA) who envisions “leading the storage industry in developing and promoting vendor-neutral architectures and standards” according to their mission statement. This is lead by the SNIA’s Storage Management Initiative (SMI). The Storage Management Initiative Specification (SMI-S) is a standard that has been developed by the SNIA.

How many more acronyms are there?

A few more.. but I’ll keep it short. These are more for reference than anything else.

  • The SMI Architecture is based on Web-Based Enterprise Management (WBEM) from the Distributed Management Task Force (DMTF).
  • The architecture is a client-server model that uses CIM-XML as the protocol. The client interface is the combination of the operations defined in CIM-XML and the model defined in SMI-S. The model is defined using the Common Information Model (CIM) and based on the CIM Schema. The EMC implementation of CIM is named ECIM.
  • The CIM is an object oriented model based on the Unified Modeling Language (UML). Managed elements are represented as CIM Classes that include properties and methods to represent management data and functions.

What is ECOM?

The EMC Common Object Manager (ECOM) enables communications and common services for applications. ECOM supports the ECIM which is used to represent the wide variety of components found in data centers using the CIM schema. The CIM schema provides a common methodology for representing systems, networks, applications, and services as a set of object-oriented models that can be bound to real-world functionality. Management applications based on CIM can interact with resources such as data storage hardware from multiple vendors, without direct knowledge of the underlying systems.

CIM classes identify types of resources. A class can represent a broad category of resources or can be subclassed to represent a specific type. For example, the class CIM_NetworkPort represents a broad category of heterogeneous network communications hardware, while EMC_NetworkPort is a subclass that represents an EMC specific subset. While classes define types of things found in a managed IT environment, instances represent individual implementations of a class. A specific port at a specific network address is an example of an instance of class EMC_NetworkPort.

The ability to exchange information, retrieve data, execute commands, and discover available resources are also required to link the elements in a network. Before resources can be managed, they must first be discovered by management applications. The Service Location Protocol (SLP) defines a mechanism for locating services in a network. Applications looking for a service are called user agents (UA), and applications providing a service are called service agents (SA). In terms of SLP, ECOM acts as a service agent that advertises its address and capabilities. When a UA has found the ECOM-exposed services that it needs, it begins communicating directly with each ECOM instance via CIM-XML messages.

A successful SMI implementation

ECOM is vital to the successful implementation of SMI. In order to successfully implement SMI there are two requirements; A WBEM Server and a SMI Provider. A WBEM server is responsible for routing of requests and management of SMI Providers. An SMI Provider will use an Application Programming Interface (API) to communicate with devices and retrieve the information in CIM format. In this scenario the ECOM service and the EMC SMI-S Provider are paired together to successfully implement an SMI-compliant interface.

EMC SMI-S Provider
Source: The EMC SMI-S Provider Programmers Guide

So what makes this the EMC SMI-S Provider as opposed to a generic SMI-S Provider? Due to the exceedingly large number of classes available in CIM and because of their broad nature, profiles were created. Profiles allow one to make use of CIM for specific domains. A profile defines the set of classes and properties that must be used to model the managed resource. The EMC SMI-S Provider is made up from the array providers. The profiles from these providers allow an SMI-S Client to retrieve information from, or make changes to specific storage systems.

First steps with the WordPress administration area

First steps with the WordPress administration area

WordPress 101 – First steps with the WordPress administration area

Now that you have finished installing WordPress on your desktop or server, it is time to get familiar with the WordPress administration area. I will take you through some of the basics of using the web interface and begin customising your website.

Logging in to the WordPress administration area

First step to using WordPress is accessing the WordPress administration area or the backend of your website. You can access the WordPress login page by adding “wp-admin” to the end of your URL (e.g. http://mywebsite.com/wp-admin). Now you will be presented with a form prompting you for a username and password. If you recall during the installation process we created a username and password which you will enter into this form. Please not this is not the MySQL username and password.

wordpress administration username passwordThe Dashboard

After logging into the administration page you will be greeted with the Dashboard. In WordPress a Dashboard is the main administration screen for a site.  It summarizes information about the site in one or more Widgets that you can add and remove. The Dashboard is also where you will plant the seeds of your new website – Creating pages, writing posts, designing the layout and making the website your own.

Starting at the top of this page we can see the toolbar.  The toolbar contains links to information about WordPress, as well as quick-links to create new posts, pages and links, add new plugins and users, review comments, and alerts to available updates to plugins and themes on your site. It also has a handy link to directly view your new website by clicking on your name.

wordpress administration toolbar

On the left side of the WordPress administration page is the main navigation menu, which is where you will perform most of your functions. As you move your cursor down this list you will see a number of sub lists pop out detailing further actions. You should get familiar with this menu – Poke around at the various options and sub menus available.

Viewing your posts

A post is a single article within a blog. What you are reading right now is a post. Assuming you are using the default WordPress theme then you will only have one post to work with in the beginning. This post will be visible on the front page, or the homepage of your website. Go take a look for yourself by navigating to your website using the WordPress toolbar. If you click on the title of the post it will bring you to the page of the post. Alternatively you can also view the post by clicking the ‘View’ button in the posts page:

wordpress administration postsPosts are usually stored in Categories and/or Tags so you can keep related topics together. Every Post in WordPress is filed under one or more Categories. Categories allow the classification of your Posts into groups and subgroups. Tags are the keywords you might assign to each post. The difference is that tags have no relationship to each other. They can be completely random for each post. Tags provide another means to aid your readers in accessing information on your blog. Looking at the screenshot above you can see that post is in the WordPress category, and does not have any tags.

Viewing your pages

Pages are not to be confused with posts. Pages are for content such as “About,” “Contact me”, etc.. For example I have an about me page. They live outside of your blogs home page. To look at your pages you can click on the ‘Pages’ option in the navigation menu. One thing to note is that normal web pages can be either static or dynamic. Static pages are created once and do not have to be regenerated every time a person visits the website. If you take a look at my about me page you might think that this is static – Nothing changes on this page whenever you visit it. However, almost everything in WordPress is generated dynamically including pages.

As I discussed in my previous post on WordPress installation everything published within WordPress is stored in the MySQL database. When the page is accessed the database information is queried by your WordPress template from your theme and the web page is generated. Technically this would be considered a “pseudo-static” page as static information is generated dynamically by the template. I will discuss this further in future posts.. Stay tuned.

By default you will not have any pages available to look at, so try creating one and see what happens. How does your page look?

Looking for more?

For now I would recommend taking a look at the WordPress Codex, but in future posts I aim to expand on the details behind pages, posts, templates, themes, plugins, and anything else related to WordPress that I can expand on..

Thanks for reading!