Tiernan's Comms Closet

Geek, Programmer, Photographer, network egineer…

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Nexdock Touch Videos

A few months back, I pre ordered a Nexdock Touch. The Nexdock Touch is a laptop without the laptop components… its essentially a screen (1920×1080 touch) with a keyboard, battery, touch pad, a 3 USB C ports (one for charging, one for phones only and one for connecting other devices) a Full USB A port (for plugging in other stuff, more on that in a sec), a Micro SD Card and a full HDMI port. Interestingly, the HDMI port is not for output, like you would think it is, but for input.

This is the Nexdock’s party piece: plug in a compatible phone (I have a Samsung Galaxy A90 5G that works), Raspberry Pi (I tried with a Pi 4) or any other device that takes USB input and HDMI output (I also tried with an Intel Nuc) and that machine becomes a laptop… Well, within reason; the Phone and the Pi will both get charged or powered by the Nexdock’s built in batter, but for the Nuc, it needs to be powered externally.

I have recorded some videos and uploaded them to YouTube. There are some unboxing videos, showing you it working with Samsung Dex and the Galaxy A90 5G, a Raspberry Pi 4 and also the Intel Nuc. The full playlist is embedded below, or you can visit the playlist on Youtube here.

I am planning on releasing more Videos in the same kind of format over the next while, so, as they say “Like and Subscribe” on YouTube if your interested!

Adding a Netgear LB2120 to the homelab

A few months back, Three Ireland came out with an LTE broadband offer: Unlimited* LTE broadband for EUR30 per month. It did come with a 18 month contract, but I pulled the trigger and got it as a backup link. I picked this up in the local Three store, and they had a couple of options for modems: a couple of Huawei mobile Wifi hotspots (E5573 or E5577) or a Huawei B525 Modem, which is designed for home use. Alternatively, there was a Sim only option, but given the modem was free with the contact, i went with the B525.

The B525 is not a bad router, don’t get me wrong, but its a Router… i already have a few of them, including my Mikrotik RouterBoard CCR1016-12G, an EdgeRouter POE, a Ubiquiti USG 3 and some virtual ones too… yea, don’t ask… What i wanted was a modem; no WiFi, no routing, and give me a full, non NATted IP to the internet. There was some mention of some of the Huawei modems being able to be put into bridge mode, but i could not find out how to do it… That’s where the Netgear LB2120 comes in.

The LB2120 (there are a few different models, but mine is the Europe edition) has a Micro SIM Slot,a WAN and a LAN port (both GigE), Power in, Power button and 2 inputs for Aerials.

The home page is fairly basic, and gives you all you need: how much data you’ve used, how much you have left, when the data plan resets, etc.

There is also an alerts option, so you can get it to send you an SMS when something happens:

But the relay handy stuff is under Advanced setting/LAN:

You have the option of using it as a router, or using it in a Bridge. Needless to say, i bridged it and got a fully public IP. Currently, mine is hooked up to the second WAN port of the USG, and is currently serving about 30-40% of the traffic on that network (mostly media devices, IOT stuff, etc). Speed wise, its not bad.

Not as good as a hardwired connection, but its only getting 4 bars, and its about 1km to the nearest cell tower. I do want to get some external aerials for it, to see if i can boost the download/upload speed, but we will see. Also, i plan on changing out the Mikrotik for something else… lets see what i end up with!

*Unlimited is mobile network speak for 750GB per month… which does not sound very unlimited to me… but, anyway…

Playing with AMD's Epyc

So, a few days back I got an email from Packet.net about a promotion they and AMD where running. Essentially, they gave me some credit for their service (i am an existing customer) to play with one of their c2.medium machines. A c2.medium comes with an AMD EPYC 7401P which consists of 24 physical cores clocked at 2Gz with an all core boost at 2.8Gb and a max clock of 3Gz, 48 threads, 64GB ECC Memory, 2x120GB SSDs for boot and 2x480GB SSDs for main storage. It also has a 20Gb network link (2x10gb bonded) and can run pretty much any OS you can think of (Windows is not on the list officially, but you can boot off your own ISO, so you could probably get it on there… might not be supported, but it might be possible). all this for $1 per hour! And did i mention they are bare metal machines?

This was the perfect opportunity to play with the new AMD processors. My current and previoius generation workstations (GodBoxv1 and Godboxv2) are both running Intel Xeon processors. the machine previous to this, the mac pro, is also running a Xeon processor. But previous to both of them, my first 2 major workstations ran AMD… the first ran 2 AMD Athlon MP processors. These were old school processors that were single core, and i cant even remember their speeds, but i do know there were 32bit only and the machine maxed out at about 1.25GB RAM (well, i had it maxed out at that). the second AMD workstation ran 2 AMD Opterons… again, single core machines, but this time, they ran 64 bit and IIRC maxed out at 8GB ram. This was a limitation of the board, not the processor…

I have been thinking about GodboxV.next, and the AMD processors, specicially the Threadrippers and Epycs, are contenders for the next machine… so, this test allows me to check them out before i buy!Why would i say no?!

So, i spun a box up in New Jersey running Ubuntu 17.10 to play with it, and here are my findings…

First, i ran lscpu on the box to see what i was playing with:

I then ran ‘fdisk -l’ to see what disks i had to play with. on my machine sda and sdb where the 480gb SSDs, sdc was a 120gb that was empty and sdd was the boot drive… i installed the ‘btrfs-progs’ and then formatted sda and sdb as a RAID0 array, which i then mounted to /mnt. this gave me just under 900gb to play with…

So, my first test is the usual test: building the Linux Kernel. I know that this is something that the lads at ServeTheHome do a lot but its something i wanted to try my self… So, first i installed git and build essential, then bison, flex and ncurses-dev, then i cloned Linus' git repo at git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git. First things first: this machine has a twin 10gb link, a shead load of cores and some very fast storage. How long did it take to clone? it download 1.02 GiB at 35.32MiB/s (about 30 seconds and about 280Mbit/s) and all in, took 2 min 55 seconds to clone. I then ran time make -j 49 to see how long it would take… hmmm… no config file… make menuconfig and just hit save… defaults are grand… time make -j 49 again… and more errors… after a bit of googling, i find the page from Ubuntu showing what i need to do to build the kernel. i follow that… download a LOT more stuff using their instructions, and finally, we get to build… Time: 6 min 12 seconds… this is a FULL default build of the kernel…

Same build on a VM on GodboxV2 (which was given 32GB RAM and 16 thread, so a full Xeon E5-4620) took 8min 27s to clone (8.18MiB/s. or about 64Mbit/s) and 36 min to build… yea, that is 3x less cores, 2x less memory, slower storage (This is on Spinny Disk, not SSD), slower network and it is also a VM VS bare metal, still, to be essentially 6 times slower? interesting… I might, at some stage, boot the machine off a live Linux USB and run some more tests, but not tonight…

So, all this is because i was holding out for the main event… Photo processing… I wanted to do something “real life”, which for me would be development and photo processing… the kernel build gives an idea of a large project build built, the image processing gives an idea of multimedia work…

so, i devised a test: Export a bunch of photos (mix of photos taken on my 5Ds, 5D MKII, iPhone 6 Plus and iPhone 7Plus) that are stored in light room as full and run them though a basic .NET Core app i wrote. the code for the app is available here. The app fully utilises the machine by using multiple threads, and because its 64 bit, it will use as much memory as it can get its hands on. It just does some basic processing: open the file, resize to 1024X1024 and then save it… the 1024X1024 part is just a test… i was a bit under the gun on time, so couldn’t spend as much time working on it as i wanted to…

In total, there was 1546 photos exported, and the total file size was 15Gb. First obstacle was to get them uploaded to the Packet machine, which took a while (my upload speed is currently 40Mbit/s)… Once up, i downloaded a copy of dotnet core 2.0 SDK, cloned the repo with the project, built and ran… and man, its fast! 4 min 43 seconds. And it used all the cores.

Running the same code on GodBoxV2 on the bare metal (no VM this time), i got 17 min 35 seconds of a run… Now, GodBoxV2 has other things running in the back ground, but not that much… I also noticed that, on average, photos were being processed in 3-5 seconds on Epyc, but nearly 13-15, and sometimes 20 and 25 seconds on GodBoxV2. I also noticed that on Epyc, the dotnet process took nearly 45GB of RAM… to run… On GodBoxV2, it took over 70!

So, there you have it. Some starting tests with these processors. I am well impressed with these processors, and would have no issue getting one for the next GodBox… And with names like Epyc and Threadripper, why not?!