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Category Archives for "Dave Tucker"

Bypassing the memory check on a VMware ESXi 5

When my new HP ML10 arrived I was ready to install ESXi… until I realised that my 32GB of RAM wouldn’t be on its way for a week! To get around the memory check in ESXi 5.5, I found the awesome instructions here and with a few tweaks was able to get this working. Here are the 20 steps that I followed…

  1. Boot the system from USB Stick with ESXi installer on it.
  2. Once the installer welcome screen shows up, press ALT+F1
  3. Login as “root”, no password.
  4. cd /usr/lib/vmware/weasel/util
  5. Delete upgrade_precheck .pyc (compiled version)
  6. Move precheck.py to precheck.py.old
  7. cp upgrade_precheck.py.old upgrade_precheck.py
  8. chmod 666 upgrade_precheck.py
  9. vi upgrade_precheck.py
  10. Type “/MEM_MIN” and press ENTER
  11. Press “i” for insert
  12. Edit the line to read “MEM_MIN_SIZE= (1*1024–32)”
  13. Press ESC and then type “:w” and ENTER
  14. Press ESC and then type “:q!” and ENTER
  15. ps -c | grep weasel
  16. Note the process id for “python”
  17. kill –9 /<process_id/>
  18. This put me back at the main screen, but you can jump back pressing ALT+F2 if necessary
  19. Continue the install process
  20. Fin

Bypassing the memory check on a VMware ESXi 5

When my new HP ML10 arrived I was ready to install ESXi… until I realised that my 32GB of RAM wouldn’t be on its way for a week! To get around the memory check in ESXi 5.5, I found the awesome instructions here and with a few tweaks was able to get this working. Here are the 20 steps that I followed…

Installing Pyenv on Mac OSX

When I’m writing code, I’m usually in OSX. When I want to try things out, or check for compatibility between certain versions of Python, it’s handy to have them all accessible… enter Pyenv. Pyenv is based on Rbenv, which for you non-Rubyists is a tools that allows you to set up Ruby environments that are scoped either globally, per-shell or per-folder!

Bypassing the memory check on a VMware ESXi 5

When my new HP ML10 arrived I was ready to install ESXi… until I realised that my 32GB of RAM wouldn’t be on its way for a week! To get around the memory check in ESXi 5.5, I found the awesome instructions here and with a few tweaks was able to get this working. Here are the 20 steps that I followed…

The definitve guide to setting up a USB Serial adapter and iTerm2 on OSX

Using a few guides on the web and a little bit of ingenuity I was able to get my FTDI-based, USB to 2x Serial adapter working in Mac OSX 10.9 Mavericks with iTerm 2. This post documents the process and resources used in the hope of becoming the definitive guide to setting up a USB serial adapter in OSX and using iTerm2 as the terminal emulator. Even if it isn’t quite definitive, it should at least be useful to others - I hope!

Choose your weapon

My Weapon of Choice

The dual serial adapter above is my weapon of choice. You can pick one up for about £20 on Amazon(not an affiliate link). Generally speaking, I’ve had better experience with FTDI chipsets so if you are in the market for an adapter, I’d recommend checking the chipset first…

Driver Installation

For FTDI

  1. Download the FTDI VCP driver for OSX
  2. Install the drivers

For Prolific

  1. Download the drivers from here
  2. Install the drivers

A quick note on terminal emulation in OSX

Most likely you have used a USB-serial adapter in Windows. When installed It appears as a COM port, you point TeraTerm or HyperTerminal to that COM port and everything automagically works. In Continue reading

The definitve guide to setting up a USB Serial adapter and iTerm2 on OSX

Using a few guides on the web and a little bit of ingenuity I was able to get my FTDI-based, USB to 2x Serial adapter working in Mac OSX 10.9 Mavericks with iTerm 2. This post documents the process and resources used in the hope of becoming the definitive guide to setting up a USB serial adapter in OSX and using iTerm2 as the terminal emulator. Even if it isn’t quite definitive, it should at least be useful to others - I hope!

The definitve guide to setting up a USB Serial adapter and iTerm2 on OSX

Using a few guides on the web and a little bit of ingenuity I was able to get my FTDI-based, USB to 2x Serial adapter working in Mac OSX 10.9 Mavericks with iTerm 2. This post documents the process and resources used in the hope of becoming the definitive guide to setting up a USB serial adapter in OSX and using iTerm2 as the terminal emulator. Even if it isn’t quite definitive, it should at least be useful to others - I hope!

Stahp it with the Network programmer FUD already

Every week I see somebody ask “will all Network Engineers be programmers” on Twitter, LinkedIn, at a trade show or just to be antagonistic and for no other reason than to start an argument.

The anger inside has been brewing for over 12 months until the pressure valve finally released in the form of this blog post. Expect snark.

What is a programmer anyway?

Lets clear something up. IF YOU CAN WRITE ONE LINE OF RUBY YOU ARE NOT A PROGRAMMER. The Programmers of myth and legend are these days referred to as “Software Engineers”, “Software Architects” and sometimes even “Hackers”, “Coders” or “Code Monkeys”. What they “do” - is build software for a living.

So what about Networking Engineers?

The networking industry can be broken in to four main segments:

Network Operations - These folk keep networks running. They eat support tickets and are seldom let out of their cages.

Network Architects - These folk run around data centers with whiteboards and sharpies and draw clouds. Consultants fall under this designation too. Occasionally these guys get their hands dirty and pick up a console cable but most times they are cooking up the most complicated solution to a simple Continue reading

Stahp it with the Network programmer FUD already

Every week I see somebody ask “will all Network Engineers be programmers” on Twitter, LinkedIn, at a trade show or just to be antagonistic and for no other reason than to start an argument.

The anger inside has been brewing for over 12 months until the pressure valve finally released in the form of this blog post. Expect snark.

Stahp it with the Network programmer FUD already

Every week I see somebody ask “will all Network Engineers be programmers” on Twitter, LinkedIn, at a trade show or just to be antagonistic and for no other reason than to start an argument.

The anger inside has been brewing for over 12 months until the pressure valve finally released in the form of this blog post. Expect snark.

Configuring the HP MSR930 for BT Infinity

After trying in vain to make my BT Home Hub 3 work as a Proper Router™ for my home lab I decided to take the plunge and get something better. Seeing as I work at HP, I thought I’d try the HP MSR 930

First step is to get your Fundamentals configured. The config below is a snippet from my configuration. This will enable SSH, SFTP, and HTTPS access from local IP addresses only.

sysname <Your Hostname>
#
# Change some web timeouts
#
web https-authorization mode auto
web idle-timeout 3
#
# ACL for Local Access
#
acl number 2000
 description *** Local Only ***
 rule 0 permit source 192.168.1.0 0.0.0.255
 rule 5 permit source 10.0.0.0 0.255.255.255
#
# Secure Web Interface
#
undo ip http enable
ip https enable
ip https port 443
ip https acl 2000
#
# SSH Setup
#
ssh server enable
ssh server authentication-timeout 10
sftp server enable
#
# Restrict VTY to SSH from Local IP's
#
user-interface vty 0 4
 acl 2000 in
 authentication-mode scheme
 protocol inbound ssh

Once we have our fundamentals done, we can get our firewall ready. Continue reading

Learning though experimentation and breaking things

Lifehacker suggested“Learning to Code by Breaking Someone Else’s Code” and I wanted to share my personal experiences with this method….

The DOS era

When I was young, 7ish, my parents bought a Packard Bell 486 machine (a DX with goofy speakers that hook on the side of the monitor IIRC). It was supposed to be for school, but as far as I was concerned it was for playing games! While the PC ran Windows 3.11, all of my games ran on DOS. DOS, as many of you probably know, has no UI, so in order to install or run a game you were at the mercy of the manual. Typically, the manual would instruct you to “cd” to a removable disk drive and run an “.exe”. This taught me some basic DOS and that an “exe” was an application that I could run.

Sound, Joysticks, IRQ and DMA

Upon running the “exe” in DOS you would be lucky if the game would run correctly first time. Sometimes you would have graphics issues, other times no sound and sometimes your joystick wouldn’t work. To get a game to work you had to select the correct drivers for graphics Continue reading

Making JSON more Readable with Sublime Text

I saw Scott Lowe’s post on how he is making JSON more readable in BBEdit and I thought I’d share how I’m doing this in Sublime Text.

If you aren’t using Package Control, you should be, so install it using the instructions here.

Open the prompt with ^⌘P then type Install and press Enter Then type Pretty JSON and press enter on more time.

Then to make your JSON pretty, you can simply ^⌘J or ^⌘P and type pretty