Docker essential tools: Dive to navigate docker image content

If you want to explore the content of a docker image, Dive is THE tool for exploring a docker image, layer contents, and discovering ways to shrink the size of your Docker image.

Note that we will be exploring the image not the container: viewing the container and the image are not the same thing. You can get most of the time a bash access to a running container with 

docker run -it image_name sh

Or following for images with an entrypoint

docker run -it --entrypoint sh image_name

NOTE: there is no guarantee that an image will have any sort of interactive shell. many minimal images contain only the binaries necessary to support a service.

An image is not running, consider it like a definition of a future container. You can still view the content, this is possible since each “layerid” directory contains json file describing layer property and filesystem associated with that layer. Docker stores Container images as layers to optimize storage space by reusing layers across images.

Beside Dive, you can also use docker inspect

docker image inspect image_id

But Dive is a lot better as it allow to navigate and see the filesystem changes in a nice norton commander interface.

Features

Show Docker image contents broken down by layer

As you select a layer on the left, you are shown the contents of that layer combined with all previous layers on the right. Also, you can fully explore the file tree with the arrow keys.

Indicate what’s changed in each layer

Files that have changed, been modified, added, or removed are indicated in the file tree. This can be adjusted to show changes for a specific layer, or aggregated changes up to this layer.

Estimate “image efficiency”

The lower left pane shows basic layer info and an experimental metric that will guess how much wasted space your image contains. This might be from duplicating files across layers, moving files across layers, or not fully removing files. Both a percentage “score” and total wasted file space is provided.

Quick build/analysis cycles

You can build a Docker image and do an immediate analysis with one command: dive build -t some-tag .

You only need to replace your docker build command with the same dive build command.

CI Integration

Analyze and image and get a pass/fail result based on the image efficiency and wasted space. Simply set CI=true in the environment when invoking any valid dive command.

To install it:

docker pull wagoodman/dive

then just provide your image tag/id/digest

docker run –rm -it -v /var/run/docker.sock:/var/run/docker.sock wagoodman/dive:latest <your-image>

Get more by visiting the project page https://github.com/wagoodman/dive 

Using free Cloudflare for CDN and DDoS protection

Cloudflare, Inc. is an American web infrastructure and website security company, providing content delivery network services, DDoS mitigation, Internet security, and distributed domain name server services. 

It will cost you 0$ (DDOS, CDN) to 20$ or more and offer you the following advantages

DDoS is short for Distributed Denial of Service. DDoSis a type of DOS attack where multiple compromised systems, which are often infected with a Trojan, are used to target a single system causing a Denial of Service (DoS) attack.

Add Docker container logs in Splunk

With Splunk You will be able to

optimize container usage by monitoring CPU, memory, disk and network performance metrics from your containers. Pay only for what you need by managing resources and measuring the impact on service reliability and container resource requirements.

Get a complete overview of Kubernetes and OpenShift Environments Correlate performance metrics, container logs and OpenShift/Kubernetes configuration and metadata for a better understanding of how your infrastructure is performing and how hosted applications are behaving.

Installing latest Splunk in 5 minutes using Docker

From 0 to Splunk in 5 minutes using Docker and Compose

Splunk is an American multinational corporation headquartered in San Francisco, California, which produces software for searching, monitoring, and analyzing machine-generated big data, via a web-style interface.

Docker is an open source software platform to create, deploy and manage virtualized application containers on a common operating system (OS), with an ecosystem of allied tools. 

Compose is a tool for defining and running multi-container Docker applications. With Compose, you use a YAML file to configure your application’s services. Then, with a single command, you create and start all the services from your configuration.

Explore 142 Initial Exchange Offering (IEO) by category, year and country

IEO is currently the most popular fundraising trend in the crypto industry. As the name suggests, Initial Exchange Offering is conducted over the crypto trading platform and exchanges. So unlike ICOs wherein crypto projects directly approach investors, IEOs involve a third-party in the form of crypto exchanges.

Security Token Offering (STO) statistics

Security token offering (STO) is a type of fundraising that is performed with a company offering tokenized securities. The defining feature of security token offerings is in its definition. Stocks, bonds and managed property trusts are another examples of securities.

Stablecoins: Crypto’s Holy Grail or Fools’ Errand? by Dr Garrick Hileman

I was attending the interesting LECTURE “Stablecoins: Crypto’s Holy Grail or Fools’ Errand?” by Dr Garrick Hileman – Head of reseach at Blockchain – London School of Economics – United Kingdom at hashtag#ETH hashtag#Zurich and here is a copy of the slides Introducing: 2019 State of Stablecoins The 2019 report builds on its predecessor to provide an updated and expanded look at the current state of the stablecoin market – a space where we expect to see significant innovation in the coming years. It includes:

• New research primers on three leading stablecoins: Paxos Standard, Stasis and Reserve
• A new in-depth comparison of Paxos Standard, USD Coin and Gemini Dollar
• Expanded data profiles on 34 stablecoins, including many new stablecoins (the report is twice the size of its predecessor!)
• Refreshed data and analysis across the full report to reflect the substantial changes observed over the last six months; and
• An overview of how to gain investment exposure to the growing use of stablecoins

Get the report and slides https://www.blockchain.com/research

Initial Coin Offering security checklist

Blockchain technology and cryptocurrencies have revolutionized the way companies raise capital but at the same time are bringing their own sets of challenges. To ensure that your startup will go through that (ad)venture in a safe manner, you should always adhere to best security practices, for your company AND your investors. 

This mind map will present you in a visual way lots of valuable information like:

• A compilation of the most dangerous threats to the ICO industry and how to mitigate,
• A set of best practices to protect your ICO from hackers,

Due to the nature of the ever-changing ICO landscape and the never-ending hackers creativity, this document will ALWAYS be a work in progress. I will continue extending it for the years to come, as long as there are interest and a value for the Blockchain community.

Feel free in comments to give me your feedback 🙂

2751 coins, 47 Consensus and 82 cryptographic algorithms

The innovation speed in Blockchain landscape is just breathtaking and being able to (or to be honest trying to…) follow all these rapid changes is a chance for all software engineers.

At the core of the Blockchain disruption are consensus algorithm:

Consensus algorithms enable network participants to agree on the contents of a blockchain in a distributed and trust-less manner.

And the consensus algorithm plays a crucial role in maintaining the safety and efficiency of blockchain. Using the right algorithm may bring a significant increase to the performance of blockchain application.

But do you know how much consensus type are out there? or where they are applied? my new Consensus Map may help you there exploring the always evolving landscape:

Here is the actual Consensus list: DPoR, DPoS, DPoS/LPoS, FBA, HPoW, LFT, Limited Confidence Proof-of-Activity, Ouroboros, POBh, PoA, PoB, PoB/PoS, PoC, PoI, PoP, PoP/PoV/PoQ, PoPP, PoR, PoS, PoS/LPoS, PoS/PoB, PoS/PoD, PoS/PoP, PoS/PoW, PoS/PoW/PoT, PoST, PoSign, PoW, PoW/DPoW, PoW/HiPoS, PoW/PoM/PoSII, PoW/PoS, PoW/PoS/PoC, PoW/PoSC, PoW/PoZ, PoW/nPoS, PoWT Proof of Believability, Proof of Existence, Proof of Ownership, Proof of Time, Scrypt-adaptive-N (ASIC resistant), TPoS, Tangle, dPoW/PoW, mFBA 

You can filter by any type of Consensus and zoom, learn more about them by hovering over the menu.

The map also feature a mode selector at the bottom, if you switch to Algorithm Map you’ll see where each of the 82 cryptographic algorithm are used!

The Map will be auto-magically regenerated every week on Sunday evening. The tedious task of maintaining the list of all Consensus algorithms (I’ve documented 60+ but only 47 are represented) and their descriptions are (still) maintained manually.

More filters will be added soon (showing for example only the top 100 by market cap, consensus by date of creation, and so on…), and your feedback is always welcomed.

Evaluating Blockchain Projects With Token Economy Canvas

Business Model Canvas is a strategic management and lean startup template for developing new or documenting existing business models. It is a visual chart with elements describing a firm’s or product’s value proposition, infrastructure, customers, and finances. It assists firms in aligning their activities by illustrating potential trade-offs.

Business Model Canvas: nine business model building blocks, Osterwalder, Pigneur & al. 2010

After reading this great article https://medium.com/@pstehlik/evaluating-blockchain-projects-with-token-economy-canvas-908bc1bab6 I felt the need to create an online editor.

“Token Economy Canvas consists of nine building blocks that are filled out in a pre-defined order. Answering the questions for each building block helps gain insight into each aspect of a blockchain project and its token. Combined, the answers allow a holistic view of the proposed token economy. From there you can make your own decision on the viability of a token or how it relates to a possible evaluation of a project. ”

The tool save regularly all your entries into browser Local Storage, so it will restore them after browser crashes, tabs closings and other disasters.

The vision

If you agree to tick the checkbox to share, all your data will be persisted to the server, in a format that later allow the Blockchain community to query, compare and read token canvas (these features are in development).

As a bonus, i also provide an excel template. Visit https://canvas.tokens-economy.com/ now 🙂