GNS3 is an excellent platform for simulating a good sized router environment for testing and more importantly for preparing for your CCIE lab. There are, however, some known limitations. The Dynamips software does not currently support more up to date switches like the 3560s used in version 4 of the CCIE Routing and Switching lab. In GNS3 on Ubuntu, you were provided with guidance on setting up GNS3 on Ubuntu GNU/Linux. You were shown how to run it as root and also introduced to the .net file that ultimately drives your lab topology. Dynamips and GNS3 (for the purpose of this article we will refer to it simply as GNS3) both support extending your virtual topology to your physical Ubuntu host. This gives us some very creative options for merging our virtual topology with physical hardware. We will use this article to demonstrate one of two different ways to extend your virtual topology to your physical hardware via some simple .net file adjustments and network configurations. You should already have a reasonable understanding of the fundamentals of Dynamips, GNS3, and the .net files before going too deep into this. You also are expected to have a reasonable knowledge of GNU/Linux and of course Cisco switching. Remember. Google is your friend.

Many people confuse object storage with block-level storage such as iSCSI or FibreChannel (SAN), but there is a great deal of difference between them. While SAN exposes only block devices to the system (the /dev/sdb linux device name is a good example), object storage can be accessed only with a specialized client app (e.g., the box.com client app).

Block storage is an important part of cloud infrastructure. Its main use cases are storing images for virtual machines or storing a user’s files (e.g., backups of all sorts, documents, pictures). The main advantage of object storage is very low implementation cost  compared to enterprise-grade storage, while ensuring scalability and data redundancy. There seem to be a couple of widely recognizable implementations of object storage. Here we’ll compare two of them that can be interfaced with OpenStack.

HyperDex is the next generation key-value store with a wide array of features. HyperDex may be a good fit for you if your application needs to:

Perform atomic transactions over multiple objects, in a fast, scalable NoSQL data store.
Store rich datatypes such as strings, integers, floats, lists, maps, and sets.
Search and retrieve objects efficiently by secondary attributes.
Ensure that your data is up to date at all times with strong consistency guarantees.
Protect your data against a configurable number of simultaneous failures.
HyperDex's key features -- namely its rich API, strong consistency, and fault tolerance -- provide strong guarantees to applications that are not matched by other NoSQL systems.

Of course, if the data is rarely modified, or it has no consistency or fault-tolerance requirements, HyperDex may not be for called for, though it still outperforms other NoSQL stores that provide weaker guarantees.

Ralph is an asset management system for your data center.
It lets you see what hardware and software is installed. It also lets you keep track of who is using every device, what is it used for and how much it costs.

I was recently confronted with the task of migrating logical volume holding MySQL databases to a separate physical volume. Due to important application running on top of MySQL any downtime was out of the question.

Easiest way to perform this operation would be using pvmove command.

Used in conjunction, NginX and Node.JS are the perfect partnership for high-throughput web applications. They’re both built using event-driven design principles and are able to scale to levels far beyond the classic C10K limitations afflicting standard web servers such as Apache. Out-of-the-box configuration will get you pretty far, but when you need to start serving upwards of thousands of requests per second on commodity hardware, there’s some extra tweaking you must perform to squeeze every ounce of performance out of your servers.