What's That Little Computer For?

A reader asks and I attempt to respond.

Yesterday night I received a question regarding what the single board computers I have are meant to do. I am going to share some scenarios where I’d use them.

Attention Conservation Notice:

This is going to be fairly tech heavy and a slightly different format - just a number of vignettes involving the use of Raspberry and Orange products. If you don’t buy random bits of gear to tinker with you’re free to move on to more productive reading.

Scenario 1: Remote Access

While it doesn’t show up much in my writing here, I’ve been installing ethernet networks for the last thirty seven years and I completed the Cisco Certified Network and Design Profession ratings twenty five years ago. I am used to doctoring things remotely and the little Orange Pi Zero 3 is going into that duty.

There are four models with 1GB, 1.5GB, 2GB, or 4GB of ram, ranging from $33 for the smallest in a plastic case to $55 for the 4GB in an aluminum heat sink. The smallest one would work for this role, but I always end up doing other things with such machines, and I never regret having extra ram.

Back when I managed wireless ISPs I would snag every dated laptop I could find. Back then they’d have onboard ethernet, wifi, and the all important DB9 serial port. I would add a second ethernet port with a USB dongle. These machines got a minimal FreeBSD install, the serial cable would go to Cisco gear in the radio shack, and the dongle would be connected to a switch port set for packet capture.

The machine being in the radio shack meant whomever climbed up there didn’t have to drag four or five pounds in a backpack, it was just there. The serial port was attached to a device console and it could be used to control the system, but the big value was that it captured all the console messages. When you have a device acting up it’s priceless to have the details on what it was doing when it crashed. Cisco switches have a feature called SPAN, which other vendors typically call port mirroring. The laptop onboard ethernet got the machine on the network, the dongle was so I could observe what was happening on whatever VLAN was having trouble. And the final bonus in this setup was the WiFi interface, which could be used to check the condition of the customer wifi cells.

These things saved guys going out in storms, or having an outage start at 8:00 PM and not being able to get someone on site until twelve hours later.

Scenario 2: Backpack Workstation

I like my Macs, but they are Apple’s computers. I’m allowed to use them, so long as I follow lots of really picky rules. If I have a 50x55x20mm box in my backpack that’ll run off laptop USB power and it’s got a real operating system on it, that is very freeing. It would be possible to examine ethernet or wifi networks; it’s easy to capture traffic and then examine it on the Mac using Wireshark.

When I did that recovery job last month I took a Pi5, a 5TB drive in a USB carrier, an empty USB-C carrier for NVMe drives, and a bunch of other random cables and adapters. I purchased a compact keyboard and a mouse, knowing the client would have a spare monitor. Like the Macs, there are things that you could never do with Windows, but those tasks are trivial using Linux. I was slinging hundreds of gigabytes and the Pi5 was the only choice - there’s no way the little Orange could handle that workload.

Scenario 3: Commissioning

One of my associates recently got a Mikrotik LtAP RB912R. I like these systems, but I’m Cisco Certified, and command line is the norm for me. They tried to set it up and found it “mystifying”.

I’m going to configure the Orange Pi Zero 3 with Ubuntu Linux and I’ll install TailScale. They’ll give me their cell phone hot spot access info so I can preconfigure for that, and it’ll be reachable via TailScale. The ethernet port gets attached to the Mikrotik and I can do the setup from here. If I did need to use a web console I would just set up a proxy on the little machine and connect to it using an ssh tunnel.

Travel to BART destinations adds up quickly, while ground shipping in the Clipper region would cost $10 - $15. The Orange Pi is inexpensive enough that a client wouldn’t flinch at the small cost, they can just toss it in a drawer when the work is done, and pull it out again as needed in the future.

Scenario 4: Management Compartment

As I mentioned in Hexnode Praxis, I’m starting to work with their Uniform Device Management service. This is web accessible and it offers remote computer/phone access for support work. The people who employ me for this sort of thing are doing so because I have technical skills AND I know a good bit about bad behavior online. I haven’t had any trouble with my systems in ten years, but it’s always possible I could slip. Having all that stuff on a machine with no network services running is comforting. If I need it, I just press a button on my KVM, and it’s there.

This setup already exists on my desktop using a Pi5. Once I have the Orange Pi in hand, I’m going to have a go at making a microSD card for it, one that protects credentials with Veracrypt. I’m not sure how I’ll access it when I’m mobile, it’ll probably be something like NoMachine, which is so much smoother than AnyDesk when the systems involved are all on the same network.

Conclusion:

These are troubled times - three attacks in December just in my little circle of contacts. I presume the temperature is going up everywhere else, too. We might be sliding into another pandemic and it’s great to have a piece of equipment that can be configured and shipped to a client, rather than risking travel.

A Pi5 would cost around $150, but a minimal 1GB Orange Pi Zero 3 with 64GB of storage is under $50. That first number is forbidding if you’re an apprentice Linux jockey, while $50 to try something new is palatable.

I really like this new generation of Raspberry Pi boards. They have 3x the processing power and memory bandwidth is 5x - 7x better than their predecessors. The 30mbyte/sec microSD cards are tolerable for light work, and if you need to go faster an NVMe “hat” and a case to hold it costs a whole $25. If you’ve got a quality NVMe SSD it’ll be 10x faster than the fastest microSD.

And now that I’ve gone as low as I can with the Orange Pi Zero 3, I’m eyeing this Orange Pi Plus. It has 32GB of memory, 256GB of eMMC storage, and dual ethernet is really enticing for the type of work I do. They’re just $245, so all I need is another big job, and I hand down a Pi5 and slip one of these into its place.