Olaf Reitmaier olafrv

macOS Internals

Understand your Mac and iPhone more deeply by tracing the evolution of Mac OS X from prelease to Swift. John Siracusa delivers the details.

Starting Points

How to use this gist

You've got two main options:

UPDATE (March 2020, thanks @ic): I don't know the exact AMI version but yum install docker now works on the latest Amazon Linux 2. The instructions below may still be relevant depending on the vintage AMI you are using.

Amazon changed the install in Linux 2. One no-longer using 'yum' See: https://aws.amazon.com/amazon-linux-2/release-notes/

Docker CE Install

sudo amazon-linux-extras install docker
sudo service docker start

3 Virtual Machines Kubernetes cluster

Dependencies

You should install VirtualBox and Vagrant before you start.

Creating the cluster

You should create a Vagrantfile in an empty directory with the following content:

Use a Windows 10 installation DVD to reliably boot into a recovery console.
Select recovery mode.
Launch Command Prompt.
Enter diskpart
Run list disk and note the desired disk number.
Run select disk <number> choosing the desired disk.
Run list volume noting the volume that is about 100 MB, FAT32 formatted. This is the EFI volume.
Run select volume <number> choosing the EFI volume.
Run assign letter=b:
exit from the diskpart utility.

Docker - How to cleanup (unused) resources

Once in a while, you may need to cleanup resources (containers, volumes, images, networks) ...

delete volumes

// see: https://github.com/chadoe/docker-cleanup-volumes

$ docker volume rm $(docker volume ls -qf dangling=true)

$ docker volume ls -qf dangling=true | xargs -r docker volume rm

Linux Laptops

Find Laptops

/r/SuggestALaptop
/r/linuxhardware
noteb.com
productchart
notebookcheck
notebookreview

Exposing a directory on the host machine to an LXC container

Log into the container and create an empty directory, this will be the mount point
Log out and stop the container.
Open to your container's config file
- For regular LXC containers: /var/lib/lxc/mycontainer/config
- For unprivileged LXC containers: $HOME/.local/share/lxc/mycontainer/config
Add a new line above the lxc.mount directive, that follows the format below. Substitute proper paths as necessary:
- lxc.mount.entry = /path/to/folder/on/host /path/to/mount/point none bind 0 0

Both of these paths are relative to the host machine.

Opening and closing an SSH tunnel in a shell script the smart way

I recently had the following problem:

From an unattended shell script (called by Jenkins), run a command-line tool that accesses the MySQL database on another host.
That tool doesn't know that the database is on another host, plus the MySQL port on that host is firewalled and not accessible from other machines.

We didn't want to open the MySQL port to the network, but it's possible to SSH from the Jenkins machine to the MySQL machine. So, basically you would do something like

ssh -L 3306:localhost:3306 remotehost

	Banco:
	<select name="banco">
	<option value=""></option>
	<option value="0156">100%BANCO</option>
	<option value="0196">ABN AMRO BANK</option>
	<option value="0172">BANCAMIGA BANCO MICROFINANCIERO, C.A.</option>
	<option value="0171">BANCO ACTIVO BANCO COMERCIAL, C.A.</option>
	<option value="0166">BANCO AGRICOLA</option>
	<option value="0175">BANCO BICENTENARIO</option>
	<option value="0128">BANCO CARONI, C.A. BANCO UNIVERSAL</option>