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NixOS, Broken ZFS pool import on LUKS Recovery

Below are the steps I used to recover the system, this is nixos running on ZFS on LUKS, where the LUKS volume is encrypted with a GPG key on a yubikey.

During a docker image build my system looked up and I had to reset my desktop by holding the power button. After that importing the zfs root pool hung on startup.

Some steps are from memory.

• Create a bootable USB drive with gpg, etc.: example

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[{"inputs": [{"internalType": "uint64", "name": "nRoots", "type": "uint64"}, {"internalType": "address", "name": "verifierAddr", "type": "address"}, {"internalType": "address", "name": "recordsMerkleTreeAddr", "type": "address"}], "stateMutability": "nonpayable", "type": "constructor"}, {"anonymous": false, "inputs": [{"indexed": false, "internalType": "address", "name": "erc20Address", "type": "address"}, {"indexed": false, "internalType": "uint256", "name": "assetDefinitionCode", "type": "uint256"}], "name": "AssetSponsored", "type": "event"}, {"anonymous": false, "inputs": [{"indexed": true, "internalType": "uint64", "name": "height", "type": "uint64"}, {"indexed": false, "internalType": "uint256[]", "name": "depositCommitments", "type": "uint256[]"}, {"indexed": false, "internalType": "bytes", "name": "minerAddr", "type": "bytes"}, {"indexed": false, "internalType": "bytes", "name": "noteTypes", "type": "bytes"}, {"indexed": false, "internalType": "bytes", "name": "transferNotes", "type": "bytes"}, {"inde

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#!/usr/bin/env bash
#
# 1. boot from live cd, with programs.gpg enabled
# 2. gpg --import /your/public/key
# 3. edit GPG_ID, DISK below
# 4. run script
#
set -euo pipefail
GPG_ID="foo@bar.com"
DISK="/dev/disk/by-id/..."

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Using Editor or IDE with colab

Note: worked in 2020, may no longer work exactly as described.

Idea: conveniently work with github repo and notebook on colab.

1. Sign up for ngrok
2. Install colab_ssh in colab notebook
3. Start tunnel
4. Provide ngrok token from https://dashboard.ngrok.com/auth/your-authtoken

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Drop other columns with pandas pivot_table

Problem: would like to use pivot_table [1] to pivot and ignore irrelevant columns in the DataFrame.

Given the DataFrame

df = pd.DataFrame(
    {

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#!/usr/bin/env bash
#
#  Usage
#
#     python2nix my_pypi_package > my_package.nix
#
#  TODO
#    - accept 'format' as arg
#    - prepopulate dependencies?
set -euo pipefail

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import click
import click_config_file
import yaml


def myprovider(file_path, cmd_name):
    with open(file_path) as config_file:
        return yaml.safe_load(config_file)

@click.command()

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#!/usr/bin/env python
"""Resize and crop images to square.

Install dependencies: pip install click Pillow

Usage: python resize.py [OPTIONS] --directory /my/image/dir --convert_directory /my/output/dir

Options:
  --directory TEXT          Directory with original images.  [required]
  --convert_directory TEXT  Where to save converted images.  [required]

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# /etc/udev/rules.d/20-bt-auto-enable-a2dp.rules
# hxss
SUBSYSTEM=="bluetooth", ACTION=="add", RUN+="/home/hxss/.config/scripts/xorg/bt-auto-enable-a2dp.sh"

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# pip install pydub scipy
import pydub.scipy_effects
from pydub import AudioSegment
from pydub.playback import play

raw = AudioSegment.from_wav("blah.wav")
six = pydub.scipy_effects.low_pass_filter(raw, 6000, order=1)

play(raw)
play(six)