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Online SAN Training – SCSI Architecture & Commands

An Online SAN Training Course – SCSI-3 Architecture and Commands – is coming up starting July 19, 2010.  I am scheduled to facilitate this course (I’m the instructor), which is open to anyone, so if you have the need or desire to attend one of my SAN training classes, please go to the link at the bottom of this page to sign up.

It is NOT free, as this is how I make my living, but the price is very reasonable.  But if you enter “Greg – Bonus Item” in the “Notes” field of the registration form, you will receive a “bonus item” along with the most current version of the In-Depth Exploration of SCSI book (the book is included with the cost of the class).   Since the book and bonus have to be shipped to you, please sign up early enough to arrive  (sorry I didn’t post this earlier).

You can see the details of the course by clicking this link, and I will be able to answer your SCSI related questions using Voice over IP (VoIP), so all you will need is your computer with a microphone connected, and we’re good.  You could also call in over the phone, but who wants to do that for 4 days in a row, for 4 hours a day.  I also attempt humor and tell “SCSI stories” to get everyone involved, and will be decoding protocol analyzer traces to show how SCSI works, what happens when it doesn’t work (that means decoding sense data), that kind of thing.  And of course if you have any specific questions, that would be the time to ask them.

These Online Training classes are usually a lot of fun, and you don’t have to travel anywhere, or for some, you don’t even have to leave your home!  Just fire up your computer (with relatively high speed internet), login each day, and we can take a deeper look at how SCSI works.

I hope to “see” you soon.

Click Here to Sign Up for the SCSI Architecture and Commands Training Course.

Secure Registration Form

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Addresses & Identifiers

Addresses and Identifiers are some of the most important parts of the Storage Networking world.  These are the parts of the system that allow use to identify what entity we are trying to connect to an communicate with. If you look at the definition of “nexus” in the SAN, it is all about the identifiers of the components.

Address vs. Identifier

I just want to be a little picky here, for just a moment about terminology.  Some protocols will use the term “Address”, when it really should be “identifier”.  For example, in networking it is very common to use the phrase “MAC Address” when the MAC is really an identifier.  It normally identifies a particular piece of hardware that is almost always at an endpoint or port to a particular device.  Addresses, if you think about it, are normally used to tell us how to get somewhere, like looking up the address of a building.  But very often there are multiple points-of-entry to a building (or device), so and address only gets us close to where we really want to go.  <Picky mode off>

Why Do We Care?

I will often hear the above question about these addresses and identifiers.  The simple answer, in most cases, is : troubleshooting! Depending on what interface and protocol we are using, we will be looking to identify what pieces of the system are involved when a problem occurs, what the source and destination device is, and what happened to cause a problem.  So if you are asked what devices and pieces of the infrastructure are involved, you need to be able to find that out.

Sample Addresses & Identifiers

Parallel SCSI – Parallel SCSI uses what are called SCSI IDs.  These are simply bits on a bus, in the range of 0 (zero) through 15.  This bits are used during the connection sequence to select, or reselect another device on the bus.

Serial Attached SCSI (SAS) – SAS uses SAS Addresses.  This is a 64-bit address that is used in the connection sequence to start (or continue) communication with another device in the SAS domain.

Fibre Channel (FC) – FC uses Source ID (S_ID) and Destination ID (D_ID) when communicating between devices.  These are in the frame header.

Online SAN Training?

I was looking at some online SAN training just yesterday, which was from a major vendor in the market, and I gotta tell you – I was not impressed. I won’t mention the vendor by name, but if I was with this particular company, I would not be happy with the quality of the product that was being produced and released to the public.

Now let me give you the conditions of this training material that I looked at. First, it was a no-cost web-based presentation.  I was not about to pay for something without knowing the quality of the content, so I wanted to try out some of their freely available material first.  I would assume that any training organization would want to offer their best material at all times, but perhaps this particular company does not share that idea when it comes to their no-cost material.

The actual “content” was very technical, which all SAN training stuff seems to be, so the hardest part is usually getting the audience “involved” in the subject matter.  The course is a 3 hour “narrated” system (voice over) of what looked like a few PowerPoint slide sets.

The Good Points:

• The presentation did work in my browser (Firefox).   Some systems I have seen require you to load a proprietary piece of software just to look at the course, but this one played just fine without any of that.
• Navigation controls available.  This system has arrows and buttons that you can click that allow you to jump around through the material, both forward and back, so that you could skip ahead or review something without having to play the whole presentation again.
• There was animation in some of the slides.  Animation is good as it helps to illustrate certain concepts, such as signal flow or action-reaction concepts, much better than straight text.
• Review questions were present.  These are good so that the student will know if they got the key concepts that were presented.

The Bad Points:

The biggest issue I have with this particular course overall is that it was BORING!  I know teaching technical topics is a challenge (from my own experience), but watching and listening to this was really painful.   Here’s why.

• Poor “acting” (voice over).  I am very picky about how I present my classes, and I could tell that whoever did the voice over for this material was either just reading a script, or was “just doing a job” to get this material out.  There was almost no “enthusiasm” at all.  I could also tell that this person had limited (if any) knowledge of the actual subject matter. In one segment, the person actually was pronouncing the words wrong! The particular subject being presented is an area where you really need to be an expert, or at least someone that has worked with the systems that are being covered.
• Poor sound quality (production issue).  One of the first things I learned when trying to make video, or web-based courses, is that the difference between a good or bad video is the sound.  Think of a TV show or movie where the sound was either not clear, or the levels jumped around from high to low and back again.  And what about those commercials that seem to blast out at you between scenes when watching TV?

I am very picky about the quality of training I provide. Even in a web or video-based environment, you have to make this material as good as you can to keep the student interested, or at least awake, through the process. I would hope that someone would review the overall product before it was released.

Even if this material is free, it needs to represent the organization at its best.  After-all, this “give-away” course should be looked at as a sales tool, and if I was the customer, I don’t think I would be buying any more training based on this offering.