Charlie Schluting

Fibre Channel (FC) has more security mechanisms built-in that most people realize. They are largely underutilized and misunderstood, so SANs are said to be a security problem. This Storage Networking 101 issue will explore FC zones: the easiest and most incorrectly configured feature of FC switches. Any decent FC switch will allow you to configure […]

Understanding the way Fibre Channel (FC) identifies domains, and a new mechanism for virtualizing your fabric, enables you to exploit these concepts to your advantage. Building a SAN isn’t difficult—you just plug things in—but to make it resilient in the face of changes, ah, there’s the rub. In this installment of Storage Networking 101, we […]

Understanding the guts of the Fibre Channel (FC) protocol itself, including the naming format and addressing scheme, allows one to better understand what’s happening on a SAN. Quickly glancing at a problem and knowing what’s wrong requires thorough knowledge of all the protocols involved. While it’s possible to operate a SAN with only point-and-click GUIs […]

As we dive deeper into SAN technology, it’s Fibre Channel’s turn to be examined. Fibre Channel, or FC, is the underpinning of all SAN technologies these days, as it won the protocol war roughly 25 years ago. FC wouldn’t be much use without something on top of it, namely SCSI. FC is the low-level transport […]

Welcome! We begin out Storage Networking 101 series with an introduction to Storage Area Networks and storage technologies. In case you missed it, be sure to read the entire Networking 101 series before embarking on the Storage journey—a solid understanding of various network protocols is required. What is a storage network? A storage network is […]

“Cluster” is probably the most heavily abused term in the computing world. In this article we’ll talk about what a cluster really is, and give an overview of the Linux technologies that can help you implement various types of clusters. The main focus will of course be on building clusters for highly available services. There […]

Last week we took the plunge and started learning about zsh. The remaining question was, "what does it take to convert an avid csh/tcsh user to zsh?" The answer was surprisingly, "not much." Zsh implements many options that will appeal to csh holdbacks. Many are limiting—they simply disable some functionality—others make the transitions smoother for […]

We can make life easier if we simply learn some new tricks, so let’s try a little experiment: I’m going to switch shells, converting everything in my tcsh configuration into zsh equivalents, and hopefully learn some new tricks. This week we’ll talk about some neat things you can do with both zsh and bash, and […]

Considering a conversion from NIS to LDAP? It may be more difficult than you plan. NIS, designed by Sun Microsystems and sometimes called a Yellow Pages directory, is a mechanism to centrally manage machine configuration data. For many reasons, LDAP is a better alternative, but switching non-trivial configurations from NIS to LDAP isn’t straightforward. This […]

Last week, we talked about some new features available in NFSv4. This week we’ll explain what’s required to get NFS servers and clients talking NFSv4, and briefly talk about the components for secure NFS. New in NFSv4 is the “domain” concept. Before NFSv4 will allow access to a file based on the user id, it […]

The consensus among many Unix and Linux users seems to be that sudo is more secure than using the root account, because it requires you type your password to perform potentially harmful actions. While sudo is useful for what it was designed for, this thinking is flawed, and usually comes from inexperience. The concept behind […]

All good things must come to an end, and so it is with Networking 101. This installment, we take a look back at everything we covered in our series. We designed the series with the belief that everyone in networking should understand all of these concepts, at least within the space constraints we gave ourselves. […]