From the blog.

Managing Digital Racket
The more I tune out, the less I miss it. But that has presented me with some complex choices for a nuanced approach to curb

Ubiquiti EdgeRouter Lite ERLite-3 Board Detail

I ran a Ubiquiti Edge Router Lite as my home firewall for a couple of years. The box had a nice GUI with CLI option, and had no problem keeping up with my > 100Mbps Internet connection. The box died after a lengthy power failure that drained the large UPS buffering electrons in my basement equipment rack. Here’s a look at its mainboard.

Stumbling And Fumbling Into Video Blogging

My first video was a good bit of work, taking roughly eight hours to write, shoot, produce, and publish a ten minute video covering some tech industry news. That’s not scalable, but it was a learning experience. Here was my process.

Auto-Adding Routes When Mac PPTP Connection Comes Up

When successfully making a PPTP connection to a remote VPN server with the built-in Mac OS X client, you find that you can’t connect to hosts on the other side of the VPN tunnel. You can still connect to the Internet and LAN hosts. The root issue is that, by default, OS X has no reason to send traffic across the VPN tunnel. A reason must be provided. I discuss 3 ways to handle this issue, including /etc/ppp/ip-up.

MacBook Battery Replacement Requires Admin Credentials?

Over the weekend, I investigated the possibility of Apple replacing the tired battery in my four year old rMBP13. Yes, they can do it. It’s $199 for that particular model. But they also require an admin-level username and password for the device. Hmm…

Connecting Python To Slack For Testing And Development

The scripting language Python can retrieve information from or publish information into the messaging app Slack. This means you can write a program that puts info into Slack for you, or accepts your queries using Slack as the interface. This is useful if you spend a lot of time in Slack, as I do.

Networking Books Up For Auction – Good Stuff Cheap

I’ve put several of my networking books up for auction on eBay. Lots of CiscoPress titles, but several others as well. Many design guides. Routing protocol coverage such as OSPF, including an OSPF vs ISIS guide by Jeff Doyle. Some are older, what I consider classics. Some are fairly new. Some are targeted at certification seekers. I need to clear some space here in my home library, and would like to move these titles along. Far too many books in my collection, and I’ve gotten what I can from these. Good luck!

Migrating From One Old Mac To Another with Factory Reset & OS X Yosemite

apple-migration-assistant-logo

I had a need this past weekend to migrate from one old Mac running OS X Yosemite to another old Mac, also running OS X Yosemite. Apple’s Migration Assistant can get this done, but I was looking to zero out the target Mac first. You can google a few different ways to do this, but I thought I’d share my high level steps and observations here, since I know a lot of you that follow this blog are Macheads.

Read more

Junos PyEZ Installation & Initial Testing on Mac OS X

I am educating myself about network automation. As I spend a lot of time in the Juniper world, a natural  place to work on automation skills is by leveraging PyEZ.

What is PyEZ?

Juniper describes it this way in their techwiki.

Junos PyEZ is a microframework for Python that enables you to remotely manage and automate devices running Junos OS.

In short, you get a bunch of classes you can act on in Python that allow you to interact with Junos devices using Python 2.7.

Read more

VMs Running In My ESXi Networking Lab as of 23-Dec-2014

Over the last several months, I’ve been building a lab full of virtual machines related to networking. I am using 2 independent ESXi hosts running vSphere 5.5 running on Haswell motherboards with 32GB of RAM, 256GB local SSDs, and a Synology DS1813+ for big, slow remote storage I access with NFS. You can read about my lab server build here.

You might be wondering why I’m bothering with ESXi. Why not just run VMs on VirtualBox on my laptop?

Read more

Cisco VIRL ESXi Installation Notes

Note: I was part of the early VIRL beta program. For my efforts in that beta, I was provided a free one year subscription to VIRL, worth $199.

I’ve got Cisco VIRL up and running on ESXi 5.5. The installation was mostly smooth, but there were some hurdles to overcome. Here are my installation notes while they are still fresh in my head.

  1. After purchasing VIRL, you have to wait to get a link where you can download VIRL.

Read more

Using Scapple To Help Manage Complex Network Changes

I’ve blogged about Scapple in the past, describing how I’ve been using Scapple to do basic network diagrams. If you are willing to give up some of the fancy features you get with an advanced diagramming tool like Visio or Omnigraffle, Scapple can take you reasonably far.

In preparation for a recent change control, I found myself frustrated by the sheer volume of CLI code I was writing. I’d work on the project at intervals separated by sometimes large chunks of time,

Read more

ThousandEyes Network Monitoring Use Cases

ThousandEyes is a network monitoring company who’s shining a light on the darkened portion of the network path you don’t own. Rather than the Internet appearing to an enterprise as a generic cloud where magic happens, ThousandEyes looks inside the cloud, revealing details about how your enterprise gets to remote services.

For example, most network engineers know that when traffic leaves their network, it will traverse a series of Internet routers before arriving at its destination.

Read more

How To Find A Lost Article In Google’s Cache

I had moment of confusion when a 1,200+ word analytical piece I’d written on HP networking utterly disappeared from my WordPress site. I still don’t know what happened. The piece was written, published, and linked all over social media. It was picking up page views immediately after publication. I’d seen some re-tweets and gotten some comments. I noticed on Saturday that the piece wasn’t seeing anymore traffic, but I was on a long hike, and didn’t have much time to think about it.

Read more

What is an Automatic Transfer Switch (Power)?

In response to the power redundancy article I wrote yesterday, a few comments came in. One of them (thanks, Mike!) mentioned an automatic transfer switch (ATS), a useful tool in a redundant power strategy.

What is an ATS? There are many types of electrical transfer switches whose primary purpose is to divert the path of electricity from one source to another, some manually and some automatically. In our context (that of data centers,

Read more

Street Power vs. UPS Power In Redundant Power Supply Devices

A question came into the Packet Pushers mailbox along these lines.

If a unit has two power inputs, should one go to UPS and one to street power, or is it better to have both power supplies fed by the same UPS?

The issue with raw street power is that it isn’t conditioned. So, voltage and amperage irregularities might happen — events affecting the power grid can also affect whatever is plugged into it.

Read more

Planning A Physical Data Center Rack Cleanup

I’m part of a project that’s going to do some physical rack cleanup. As in, the cables are a mess, labeling isn’t consistent, power distribution isn’t quite what it should be, and it’s gotten to the point where doing maintenance on any of the hardware is tough. So, it’s time to tidy everything up. I’ve been a part of several of these kinds of projects before, and I’ve collected a bunch of data on how to approach it.

Read more