Quantifying who’s going past my house I live on a busy road leading into a suburb. In term time rush hour it’s not uncommon to have a queue of traffic right outside our house. Within days of the UK going into lockdown on the 23rd of March there was a noticable drop in traffic as you’d expect. It wasn’t long however before it felt like people were starting to venture out again in their cars.

With the Raspberry Pi having a good hardware random number generator and virtual machines and containers potentially having so little, especially shortly after boot, it makes it a cheap source. Amazon’s SQS provides a fully managed, reliable message delivery system and it’s cheap, free at low volume. This seems like an excellent way to deliver Entropy to all your virtual infrastructure. Sending Entropy to the Queue Once you’ve created an SQS queue this python code will periodically (sleepfor) fetch the queue length if it’s below (lowwatermark) it will add (burstadd) messages to the queue, each message will contain 512 bytes of base64 encoded entropy.

The Raspberry Pi has long come with a hardware random number generator, it’s right here: /dev/hwrng but the OS isn’t using it by default. You can test the quality of it’s output with the ent utility dd if=/dev/hwrng bs=1k count=1 |ent example output: 1+0 records in 1+0 records out 1024 bytes (1.0 kB, 1.0 KiB) copied, 0.00956855 s, 107 kB/s Entropy = 7.833804 bits per byte. Optimum compression would reduce the size of this 1024 byte file by 2 percent.

git branch -r –merged |grep -v master |sed ’s/origin///' |xargs -n 1 git push –delete origin

cURL is an amazing tool, chain it along with jq and you’ve got a JSON parsing API reader right there in your shell. But it’s so much more, so here are a few ways I’ve used it in the past. Firstly say you want to verify a file of URLs to check they all return 200, you can do that in one line: cat file.txt |while read line; do echo -n $line returns: && curl -s --max-time 2 -o /dev/null -w "%{http_code}" $line;echo;done Outputs: www.

There’s been a lot of talk about Entropy as a Service lately and as someone with an interest in security it got me thinking why, what devices are really lacking entropy such that they’d risk pulling in someone else’s… IoT devices needing to generate Strong cryptographic keys on or shortly after boot, Gitlab runners (Docker containers where /dev/random is not passed from the parent). Sounds like there is a need.

Why I exist I’d been using the tram for years, it’s great mostly. Whenever there was a problem I’d invariably turn around and drive home and just work from home. Great if your job allows but annoyed I’d driven to Toton and back unnecessarily. Often the info was there just waiting to be read over on Twitter but I’d miss it, forget to check. What to do 🤔 well if you favourite a Twitter account you’ll get a push notification every time they tweet, problem solved I thought, only they tweet good morning, which is nice I get it but I don’t want my phone going off everyday, just when there’s a problem.