The Usual Tech Ramblings

1Password and Broken Certificate Chains

A while back I switched to a Linux based desktop for my work machine as I’d been doing a lot of work in ansible, and having to keep messing with VMs, SSH, and various other hoops was just getting annoying. I’d wanted to experiement for a while anyway. That’s another set of posts. This one is about the 1Password client, and certificate chains.

Changing certbot validation plugin

I use letsencrypt for a number of SSL certificates, from websites to mail services. The easiest, and documented, way of requesting certificates is via certbot. This is a utility that makes requesting certificates easy. I won’t go into the details on how to do that, there’s plenty of guides, and even the documentation gives you some straight forward steps.

Stop The Bleed

May has been announced as the first “National Stop the Bleed” month. The “Stop the Bleed” campaign is trying to empower the general public to know how to deal with life-threatening emergencies usually involving rapid blood loss. There are many situations that this could be useful for a bystander, from car accidents to gardening disasters to gun shot injuries.

Raspberry Pi and the dreaded undervoltage notifications

I’ve been tinkering around a bit with some Raspberry Pi devices for a number of little projects. Most have been related to home automation type stuffs, but I built one with a 7” screen that I was going to be using for radio related things. Originally I had tossed together a small kit with an SDR for use on a camp because I knew we’d be out of range of cell phone service, but knew I could still take advantage of radio frequencies from satellites to get data, specifically weather images.

All seemed to go quite nicely, however I’d sporadically get a lightening bolt in the top right corner of the screen. I later learned that was a sign that the Pi wasn’t getting enough voltage. This baffled me, I was using a decent 5v power source, why would I get a low voltage issue? So I decided to do some research.

Powershell and Single vs Double Quotes

There can be a lot of confusion over when to use single and double quotes in PowerShell. Not to worry, this confusion carries over in a lot of programming and scripting languages, such as Perl. I figured, after seeing this tweet, to give a quick run down of when to use which one.

Powershell and Progress Feedback

We’re in the process of enabling a new password reset portal, which requires additional licensing features in Office 365. There is no “apply all” button in Office 365, so we have to do this via script to tens of thousands of user accounts. The problem with this is some form of feedback to the user running the script. PowerShell has some really handy built in features, such as a progress bar. It’s amazing how something so simple can make you feel a little better, and actively see how things are moving along. Progress bars in PowerShell are incredibly simple.

Custom Windows installs, injecting drivers and features

One of the things about new platforms is you get to learn new technology. One of the bad things about new technology is that a lot of your old methods might not apply anymore, need to be revamped, or redesigned completely. Over the last few months I’ve been working on a Cisco UCS platform deployment for work. This has been quite exciting as it’s all new gear, and it’s implementing stuff that we should have been able to implement with our HP BladeSystem C7000 gear.

vSphere Storage vMotion times out at 32% when crossing SANs

A year or so ago we’d upgraded our vCenter from 4.1 to 5.1, and with this upgrade, and some features built into our SAN, we got access VAAI. For example, removing a VM guest would tell the SAN that the guest had been removed, and if the data store had been thinly provisioned from the SAN, it’d clean up and shrink down the space used (in theory).

Another feature we discovered was something called “fast copy”. In layman’s understanding of this feature, when a storage vMotion request was created, the SAN was notified of the request, and the SAN would process the copying of the bits in the background. This is handy because it stops the data from being sent from SAN to host to SAN again. This causes a good speed up with regards to moving machines around.