Visual Subnet Calculator


I’m a sysadmin/consultant by trade. I cut my teeth on IPv4 addressing way back in the NT4 days when most addressing was still class based.

I never really got the hang of CIDR addressing but I understood the rationale and concepts of it. I was never very good at finding a good approach to subnetting and CIDR mask determination though. Usually there was a network person’s brain handy to have a conversation with and that got me by.

Then along came public Cloud and the rules for CIDR address allocation and subnetting changed again. I knew that the old approach to subnet determination wasn’t really good for the public Clouds and all the docs from the vendors wanted you to assign a /16 to every VPC/vNet you created. This always felt wasteful and like overkill to me.

I decided to hunt around for something that could help me and found this tool. Visual Subnet Calculator

Faith in Humanity has received an additional skill point


I wanted to offer a big thank you to someone who will never read this.

We had that unfortunate event last week where someone clipped the drivers side mirror on our car. The mirror assembly was snapped right off and the glass shattered.

Fortunately, the person who did this was a professional driver who ensured that the mirror housing was recovered and placed on the car and also left an apologetic note with their contact details.

My first thought was of course that the contact details left are probably not real. We’ve had this problem before where someone damaged our car, left a note with their number but somehow managed to leave one digit off their number. Yay.

I called the number on the note and spoke to Mohammed. He was very apologetic and immediately offered to pay to have it repaired without involving insurance. I got some quotes for the repair, sent them to him, he transferred the money to us and we got the mirror fixed.

Neat, simple and quick.

I wanted to put a huge thank you out there to Mohammed for this ownership of the accident and the prompt fixing of it.

The Key to Becoming a Software Consultant – DaedTech


via The Key to Becoming a Software Consultant – DaedTech

Rewire your brain to beat procrastination – Taking Note – Medium


I related to this SO HARD!

via Rewire your brain to beat procrastination – Taking Note – Medium

Update Synology DNS records from DHCP IP address reservation – GitHub – gclayburg/synology-diskstation-scripts



Ive had Synology devices running my core home network services for a few years now and it has always frustrated me that some sort of DHCP/DNS integration wasnt possible. Recently though this because more frustrating because I setup a Raspberry Pi on my home LAN and installed Pi-Hole.

Pi-Hole did the needful thing and helped enormously. The problem though was that the Pi-Hole logs only showed the clients IP address, not the computer name. Pi-Hole can do reverse look ups for client IP addresses but only if your DNS server has the zone setup and data in the zone file. Because Synology DNS and DHCP aren’t integrated then clients wouldn’t have their names registered in DNS and Pi-Hole couldn’t resolve the reverse lookup for the machines IP address.

I finally found a magic script to fix this. See GitHub – gclayburg/synology-diskstation-scripts: Update Synology DNS records from DHCP IP address reservation.

Dead easy to setup and works like a charm.

Activating Telstra OneNumber on a business account.


I have this morning managed to activate Telstra OneNumber on my iPhone which uses my employers business account. This completes an enquiry I lodged with Telstra back in January.

For anyone else who wants to do this you must:

  1. Ensure you have the authority and/or password for the business account to change services on the account. See your account owner.
  2. Make a note of your company’s ACN/ABN. You might be asked for it.
  3. Make a note of the address your company has on record with Telstra.
  4. Called Telstra on 132000. You must specifically request the activation of OneNumber on a business account.
  5. The operator will take some information from you and advise you that you will get a call back in 5-7 business days. You will also be given a case number. Do make a record of this.
  6. You will be given instructions on what to do in case Telstra doesn’t call you back.
  7. You will not be told that when(if?) Telstra does call you back that you will need the password on the business account. Make sure you have it ready for later.
  8. After 5-7 days Telstra will call you back and manually sign up your service thats attached to the Business account. You will be read some T&Cs, you will be read a risk statement. You must verbally accept these on the phone.
  9. You can then restart your iPhone, open the Watch App and activate the service.

I wont make any comments about this process and how long it took for me to be told about it.

New – Amazon Linux WorkSpaces


Over two years ago I explained why I Love my Amazon WorkSpace . Today, with well over three years of experience under my belt, I have no reason to return to a local, non-managed desktop. I never have to worry about losing or breaking my laptop, keeping multiple working environments in sync, or planning for disruptive hardware upgrades.