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Where the Cloud Touches Down: Simplifying Data Center Infrastructure Management

Thursday, July 25, 2013
10:00 AM PT/1:00 PM ET

In most data centers, DCIM rests on a shaky foundation of manual record keeping and scattered documentation. OpManager replaces data center documentation with a single repository for data, QRCodes for asset tracking, accurate 3D mapping of asset locations, and a configuration management database (CMDB). In this webcast, sponsored by ManageEngine, you will see how a real-world datacenter mapping stored in racktables gets imported into OpManager, which then provides a 3D visualization of where assets actually are. You'll also see how the QR Code generator helps you make the link between real assets and the monitoring world, and how the layered CMDB provides a single point of view for all your configuration data.

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A Network Computing Webinar:
SDN First Steps

Thursday, August 8, 2013
11:00 AM PT / 2:00 PM ET

This webinar will help attendees understand the overall concept of SDN and its benefits, describe the different conceptual approaches to SDN, and examine the various technologies, both proprietary and open source, that are emerging. It will also help users decide whether SDN makes sense in their environment, and outline the first steps IT can take for testing SDN technologies.

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Crash Course: Router Redundancy Protocols

Start in the Middle

Adding redundancy is the most common way to increase your uptime, and the best approach is to start in the middle and work your way toward the edge. First, make sure there's redundancy within your core router--redundant CPU cards, power supplies and fans usually can be added to chassis-based routers and switches, and some router and switch vendors have equipment with dual backplanes. Each vendor does this differently, and in some cases, an outage occurs when the backup card takes over, but usually only new routes are affected while the new card comes up. With redundant CPU cards, you can force a failover to one card while you upgrade the second one, instead of having to bring the whole router down for the upgrade.

The core or backbone of a network usually handles the most traffic so, if it goes down, it will likely affect the most users. If your redundant core router or switch equipment is connected and ready to kick in automatically when a problem occurs, you can reduce an outage from hours of manual labor to an automated process that takes just a few seconds. This is called High Availability, where identical core routers must be ready to take over should the primary fail (see "Three Tiers for HA," above right). This means that the next layer out, the aggregator switches, has to have a connection to each router, which also provides some redundancy for the links themselves--which also lets you put each core router in different geographic locations.

Proper Protocols

Now that your network has redundant links, you must decide how packets on the network will select their paths and avoid loops. This isn't a new problem--redundant paths have been addressed by protocols like STP (Spanning Tree Protocol) at Layer 2 and routing protocols like the IETF's OSPF at Layer 3. But these protocols can take 40 seconds or more to resolve. OSPF takes up to 30 seconds to resolve; STP, even more. This is unacceptable for critical networks, especially those with real-time applications like VoIP and video.

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