Our Authentication & Quality Assurance Procedure For Creating Parabola GNU/Linux-libre Installation Media

Below are our authentication steps & quality assurance procedures for creating Parabola GNU/Linux-libre installation media:

# Download Parabola GNU/Linux-libre from parabola.nu

wget https://redirector.parabola.nu/iso/x86_64-systemd-cli-2022.04/parabola-x...

2023-02-13 19:13:28 (15.8 MB/s) - ‘parabola-x86_64-systemd-cli-2022.04-netinstall.iso’ saved [648019968/648019968]

# Download SHA512SUMS file & signature

wget https://repo.parabola.nu/iso/x86_64-systemd-cli-2022.04/SHA512SUMS

2023-02-13 19:14:18 (55.7 MB/s) - ‘SHA512SUMS’ saved [181/181]

wget https://repo.parabola.nu/iso/x86_64-systemd-cli-2022.04/parabola-x86_64-...

2023-02-13 19:15:29 (90.1 MB/s) - ‘parabola-x86_64-systemd-cli-2022.04-netinstall.iso.sig’ saved [310/310]

# Check the integrity of the downloaded ISO

sha512sum -b parabola-x86_64-systemd-cli-2022.04-netinstall.iso

58e521c90a68234cbb0935b41984af37852362ea3b953cc7493bcf7ff664334e267bd643e43e29eeb2b454a1d08cce0ead6dca2cccae0dffb471cc8b93caf5ec *parabola-x86_64-systemd-cli-2022.04-netinstall.iso

# Check the above string 58e52...f5ec matches the blow hash

cat SHA512SUMS

58e521c90a68234cbb0935b41984af37852362ea3b953cc7493bcf7ff664334e267bd643e43e29eeb2b454a1d08cce0ead6dca2cccae0dffb471cc8b93caf5ec parabola-x86_64-systemd-cli-2022.04-netinstall.iso

(and for us it did)

# Import signing key

gpg --keyid-format long --keyserver hkp://pgp.cyberbits.eu --recv-keys 0x5A8D4B40

# Verify the authenticity of ISO: The output of the below command should tell you that the file signature is a
# "good signature". If you see a warning about not being certified with a trusted signature this is normal.

gpg --keyid-format long --verify parabola-x86_64-systemd-cli-2022.04-netinstall.iso.sig parabola-x86_64-systemd-cli-2022.04-netinstall.iso

gpg: Signature made Sat 07 May 2022 06:26:26 AM EDT
gpg: using RSA key FBCC5AD7421197B7ABA72853908710913E8C7778
gpg: Good signature from "bill-auger " [unknown]
gpg: aka "bill-auger " [unknown]
gpg: aka "bill-auger " [unknown]
gpg: aka "[jpeg image of size 6017]" [unknown]
gpg: WARNING: This key is not certified with a trusted signature!
gpg: There is no indication that the signature belongs to the owner.
Primary key fingerprint: 3954 A7AB 837D 0EA9 CFA9 7989 25DB 7D9B 5A8D 4B40
Subkey fingerprint: FBCC 5AD7 4211 97B7 ABA7 2853 9087 1091 3E8C 7778

# Plug in a USB flash drive and unmount any auto-mounted partitions to ensure reliability of written image
# At a minimum make sure the size of the flash drive matches what you inserted to avoid accidentally
# overwriting important data

sudo fdisk -l

Disk /dev/sda: 59.75 GiB, 64160400896 bytes, 125313283 sectors
Disk model: Flash Drive
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: 07896644-3E61-4841-B41A-CA3F44823CCE

Device Start End Sectors Size Type
/dev/sda1 128 125313250 125313123 59.8G 7 HPFS/NTFS/exFAT

# So we're going to run the follow commands as the flash drive above we are using has mounted partitions

sudo umount /dev/sda1

# Write the Parabola GNU/Linux-libre ISO to disk

sudo dd if=parabola-x86_64-systemd-cli-2022.04-netinstall.iso of=/dev/sda bs=16M oflag=direct status=progress

637534208 bytes (638 MB, 608 MiB) copied, 18 s, 35.0 MB/s
38+1 records in
38+1 records out
648019968 bytes (648 MB, 618 MiB) copied, 18.5924 s, 34.9 MB/s

# Run the sync command to flush any data to disk and make sure it's written

sync

# Identify the size of the ISO image using the stat command

stat -c '%s' parabola-x86_64-systemd-cli-2022.04-netinstall.iso

648019968

# Along with the above number output use the head command to check the portion of the disk we've written
# the ISO to prior; also it isn't a bad idea to unplug the USB drive and connect it again
# Replace /dev/sda with your flash drive location

sudo head -c 648019968 /dev/sda | sha512sum

58e521c90a68234cbb0935b41984af37852362ea3b953cc7493bcf7ff664334e267bd643e43e29eeb2b454a1d08cce0ead6dca2cccae0dffb471cc8b93caf5ec -

# Make sure the output above matches what is in the sha256sum.txt file we downloaded earlier

cat SHA512SUMS

58e521c90a68234cbb0935b41984af37852362ea3b953cc7493bcf7ff664334e267bd643e43e29eeb2b454a1d08cce0ead6dca2cccae0dffb471cc8b93caf5ec parabola-x86_64-systemd-cli-2022.04-netinstall.iso

# In this case the above matches so we can conclude that the ISO image is fully and properly written to disk