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Posts tagged ‘Tech’

Teaser: NTP Wall Clock Project

If you’ve followed my Instagram recently (and lets face it, no you haven’t) you might have noticed these cryptic posts with imagery of a pile of electronics with some enormous 7-segment displays strewn on top (see exhibit A)

What I’ve been working on is a long term dream of mine, a clock that never needs you to set the time, thanks to the fact that it updates itself using the NTP system over the Internet. A big part of this stems from childhood trauma from DCF77 receiving clocks (only a German could think of broadcasting time with an offset from UTC with a signal strong enough to cover most of Europe) and a decade of my life in the IT industry, where incorrect time is altogether a too common root cause of issues (it should be indistinguishable from 0 in 2017 one would think).

I’ve currently worked out the hardware for the basic clock, and will be doing a more thorough post about this project as I manage to finalise it, but as there seems to be very little information on the topic on the Internet, I though someone else might be looking for just this thing at this very moment, and so that you don’t have to work out everything from different sources as I did, here’s a link to my GitHub project, where you can download the code actually works!

https://github.com/grumpytechie/ntpclock

The GitHub will eventually host all the steps to getting this to work, but with a glancing understanding of electronics and Raspberry Pis you should be able to make it work (hey, after all, I managed to cobble it all together, didn’t I?).

I’ll be back in a few weeks as I finalise the enclosure as well as the power supply!

 

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How to Factory Reset a HP Procurve / Aruba Switch – HP Networking Series Part 5

© Mishoo | Dreamstime.com - Network Hub Photo

© Mishoo | Dreamstime.com – Network Hub Photo

Sometimes it might be helpful to reset an HP Procurve / Aruba switch to it’s default factory config, and weirdly it took me until my 153rd installed switch (yes, I actually looked up how many I’ve installed over the years for this) before I needed this command, so I had to not only Google it, but also dig trough the command reference until I actually managed to find the command I was looking for. Therefore, I made this post for Google to index, so that when you need it, you’ll be able to find it quicker!

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Upgarding vRealize Operations Manager to 6.6

 

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Updating appliance VMs can be a bit of daunting process since they are all usually different. vROPS (VMware vRealize Operations) is no different in that regard, but it’s a quite straightforward operation when you get understand the process.

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Updating VMware vRealize Operations Manager Appliance

 

vrops6-title

Updating appliance VMs can be a bit of daunting process since they are all usually different. vROPS (VMware vRealize Operations) is no different in that regard, but it’s a quite straightforward operation when you get understand the process.

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How to Crimp SMA Connectors to RG58 Cable

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The World’s Longest Console Cable – Smartflex Router Series

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As everybody knows, console cables and their corresponding interfaces are a scourge on a network administrators existence. They are always too short, COM-ports get renumbered, Baud-rates are unknown, etc. By their very nature, you also have to be physically present in the vicinity of the box you’re trying to configure. Today we’re going to change all that, by constructing a wireless console cable adaptor with almost infinite range.

I can almost here people shouting something about SSH and Telnet to their screens, as well as something about the Airconsole. First and foremost, telnet and SSH are both wonderful, after you’ve configured the device, but for initial setup, they sadly can’t be used. Airconsole is quite nice, and I use it almost daily, but it’s useful when you want to sit somewhere comfortable when configuring a device in the same room as you, not so much when you want to be comfortable on a beach half a world away from the offending device.

This we’re going to change today, with one device, the B+B SmartFlex router.

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How to Stack HPE/Aruba 2920 Switches – HP Networking Series Part 4

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The 2920 series switches from HPE/Aruba has a special feature that no other switches in the old ProCurve/E-Series line-up has; dedicated stacking interfaces. On other HPE switches, stacking merely facilitates “simplified” management, by allowing you to manage any switch in the stack from the stack commander’s CLI. On the 2920 series however, you can use dedicated stacking interfacing, giving you 2 20 Gbps links to other switches in the stack and merging two to four switches into one coherent switch. This is quite similar on how stacking works on some Cisco models, but the specialized stacking interfaces gives you higher speeds between the members. In this article, I’ll show you have to set up the commander switch and how to add switches to the stack once it’s created. I’ll also go into how it affects the configuration of the switches, which is quite crucial if you want to stack switches that are already in production.

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FreeNAS: Migrating a RAID-Z vdev to a RAID-Z2

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For the last couple of weeks, I’ve been playing around with a FreeBSD distribution that’s quite interesting, FreeNAS. FreeNAS basically turns any old box you have lying around into a NAS, though you should definitely not run it on any old box. The only problem was, I got a bit excited when setting up my system, so I configured a RAID-Z vdev for my zpool. Technically, this was not an issue at the time when I set up the pool, since I was using old leftover 160GB and 250GB drives. But after a while I replaced the 160GB drives with two 1 TB drives I had laying around. And a couple of days later, I ordered 2 4TB drives to replace the 250GB ones. And then RAID-Z started to be a problem. You see, RAID-Z suffers from the same problems as RAID5, aka. that if you set up an array with large SATA drives (1 TB or larger), and one drive fails, you’re almost guaranteed a bad day (if you’re not running enterprise grade drives, more on this later in a separate post). So before I went and installed the new drives I migrated my whole pool to a backup drive and destroyed the old vdev and pool. Here’s a short guide on how I, relatively successfully did it. Read more

Problems installing Windows 10 from scratch?

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I recently had to do a reinstall of Windows 10 on a 3 year old Lenovo desktop. I previously updated the machine from Windows 7 to Windows 10, and shortly thereafter the hard drive started to give intermittent issues, so I decided to upgrade the machine with a SSD and do a clean install of Windows 10 at the same time. Turns out, installing Windows 10 from scratch isn’t that easy, so here are some of the things I discovered while researching the issue.

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VMware Client Integration Plug-In not Working in Chrome?

If you have experienced a problem with the vSphere Client Integration Plug-In not working even though it’s installed in Google Chrome, you’re not alone. Seems like Google decided to disable NPAPI (Netscape Plugin Application Programming Interface) from version 42 of Chrome onwards. The vSphere Client Integration Plug-In (henceforth known as the plug-in) utilizes the NPAPI to interact with Chrome, and Google is currently trying to phase out that particular API. The name should give you an idea of the age of that particular API (youngsters, go google Netscape and prepare to be amazed), and Google’s reasons for retiring it are quite understandable. VMware, on the other hand, are as usual quite tardy when it comes to supporting changes to Chrome, so it might be a while before we will see a new plug-in supporting a newer API.

Update: Chrome 45 has rolled around and removed NPAPI altogether, VMware has finally done something about it, see my latest post on the issue here.

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