bootc-docs/exec-in-host-mount-namespace/bootc-exec-in-host-mount-namespace-external-commands.md

bootc exec-in-host-mount-namespace - External Commands Reference

Overview

This document provides a comprehensive reference for all external commands used by bootc exec-in-host-mount-namespace operations. These commands are essential for understanding the dependencies and integration points of the exec-in-host-mount-namespace system.

Core Commands

bootc

Purpose: Main bootc command for exec-in-host-mount-namespace operations Usage: bootc exec-in-host-mount-namespace [ARGS]... Dependencies: None (core command)

Examples

# Execute command in host mount namespace
bootc exec-in-host-mount-namespace ls /

# Execute with arguments
bootc exec-in-host-mount-namespace mount /dev/sda1 /mnt

# Execute system command
bootc exec-in-host-mount-namespace systemctl status

System Commands

setns

Purpose: Change namespace membership Usage: setns [options...] <file> [program [arguments...]] Dependencies: util-linux

Examples

# Change to mount namespace
setns /proc/1/ns/mnt /bin/bash

# Change to PID namespace
setns /proc/1/ns/pid /bin/bash

# Change to network namespace
setns /proc/1/ns/net /bin/bash

unshare

Purpose: Run program in new namespaces Usage: unshare [options...] [program [arguments...]] Dependencies: util-linux

Examples

# Create new mount namespace
unshare -m /bin/bash

# Create new PID namespace
unshare -p /bin/bash

# Create new network namespace
unshare -n /bin/bash

# Create multiple namespaces
unshare -m -p -n /bin/bash

nsenter

Purpose: Enter namespaces Usage: nsenter [options...] [program [arguments...]] Dependencies: util-linux

Examples

# Enter mount namespace
nsenter -m -t 1 /bin/bash

# Enter PID namespace
nsenter -p -t 1 /bin/bash

# Enter network namespace
nsenter -n -t 1 /bin/bash

# Enter multiple namespaces
nsenter -m -p -n -t 1 /bin/bash

Filesystem Commands

mount

Purpose: Mount filesystems Usage: mount [options...] <device> <directory> Dependencies: util-linux

Examples

# Mount filesystem
mount /dev/sda1 /mnt

# Mount with options
mount -o ro,noexec /dev/sda1 /mnt

# Mount bind
mount --bind /source /target

# Mount tmpfs
mount -t tmpfs tmpfs /tmp

umount

Purpose: Unmount filesystems Usage: umount [options...] <directory> Dependencies: util-linux

Examples

# Unmount filesystem
umount /mnt

# Force unmount
umount -f /mnt

# Lazy unmount
umount -l /mnt

# Unmount all
umount -a

chroot

Purpose: Change root directory Usage: chroot [options...] <directory> <command> Dependencies: coreutils

Examples

# Change root
chroot /mnt /bin/bash

# Change root with specific command
chroot /mnt /bin/ls

# Change root with environment
chroot /mnt env -i /bin/bash

chdir

Purpose: Change working directory Usage: chdir <directory> Dependencies: coreutils

Examples

# Change to root directory
chdir /

# Change to specific directory
chdir /var/lib/bootc

# Change to home directory
chdir ~

Process Commands

exec

Purpose: Replace current process Usage: exec [command [arguments...]] Dependencies: coreutils

Examples

# Replace with new command
exec /bin/bash

# Replace with command and arguments
exec /bin/ls -la /

# Replace with shell
exec /bin/sh

ps

Purpose: Process status Usage: ps [options...] Dependencies: procps

Examples

# Show all processes
ps aux

# Show process tree
ps -ef

# Show specific process
ps -p 1234

# Show processes by user
ps -u username

kill

Purpose: Send signals to processes Usage: kill [options...] <pid> Dependencies: util-linux

Examples

# Kill process
kill 1234

# Force kill process
kill -9 1234

# Send signal
kill -TERM 1234

# Kill by name
pkill process_name

System Information Commands

uname

Purpose: System information Usage: uname [options...] Dependencies: coreutils

Examples

# Show system name
uname

# Show all information
uname -a

# Show kernel name
uname -s

# Show kernel version
uname -r

# Show machine type
uname -m

hostname

Purpose: Hostname operations Usage: hostname [options...] Dependencies: hostname

Examples

# Show hostname
hostname

# Show FQDN
hostname -f

# Show short hostname
hostname -s

# Show domain name
hostname -d

lscpu

Purpose: CPU information Usage: lscpu [options...] Dependencies: util-linux

Examples

# Show CPU information
lscpu

# Show in JSON format
lscpu -J

# Show in extended format
lscpu -e

# Show in parseable format
lscpu -p

free

Purpose: Memory information Usage: free [options...] Dependencies: procps

Examples

# Show memory usage
free

# Show in human readable format
free -h

# Show in bytes
free -b

# Show with total
free -t

# Show with wide format
free -w

File Commands

ls

Purpose: List directory contents Usage: ls [options...] [file...] Dependencies: coreutils

Examples

# List files
ls

# List with details
ls -l

# List all files
ls -a

# List with human readable sizes
ls -lh

# List with recursive
ls -R

# List with sort by time
ls -lt

find

Purpose: Find files Usage: find [path...] [expression] Dependencies: findutils

Examples

# Find files by name
find /path -name "*.txt"

# Find files by type
find /path -type f

# Find files by size
find /path -size +100M

# Find files by modification time
find /path -mtime -7

# Find files by permissions
find /path -perm 644

stat

Purpose: File status Usage: stat [options...] [file...] Dependencies: coreutils

Examples

# Show file status
stat file.txt

# Show in custom format
stat -c "%n %s %Y" file.txt

# Show filesystem status
stat -f /path

# Show with format
stat --format="%n: %s bytes" file.txt

Storage Commands

df

Purpose: Disk space usage Usage: df [options...] [file...] Dependencies: coreutils

Examples

# Show disk usage
df -h

# Show specific filesystem
df -h /var/lib/bootc

# Show inode usage
df -i

# Show all filesystems
df -a

du

Purpose: Directory space usage Usage: du [options...] [file...] Dependencies: coreutils

Examples

# Show directory usage
du -h /var/lib/bootc

# Show total usage
du -sh /var/lib/bootc

# Show usage by subdirectory
du -h --max-depth=1 /var/lib/bootc

# Show usage of all files
du -ah /var/lib/bootc

lsblk

Purpose: List block devices Usage: lsblk [options...] Dependencies: util-linux

Examples

# List block devices
lsblk

# Show device tree
lsblk -f

# Show device sizes
lsblk -b

# Show device types
lsblk -d

Network Commands

curl

Purpose: HTTP client for registry operations Usage: curl [options...] <url> Dependencies: curl

Examples

# Download file
curl -O https://example.com/file.tar

# Get HTTP headers
curl -I https://example.com

# POST data
curl -X POST -d "data" https://example.com

# With authentication
curl -u username:password https://example.com

# With custom headers
curl -H "Authorization: Bearer token" https://example.com

wget

Purpose: HTTP client for downloading files Usage: wget [options...] <url> Dependencies: wget

Examples

# Download file
wget https://example.com/file.tar

# Download with progress
wget --progress=bar https://example.com/file.tar

# Download recursively
wget -r https://example.com/

# Download with authentication
wget --user=username --password=password https://example.com

Systemd Commands

systemctl

Purpose: Systemd service management Usage: systemctl <subcommand> [options...] Dependencies: systemd

Examples

# Check service status
systemctl status bootc-*

# Start service
systemctl start bootc-*

# Enable service
systemctl enable bootc-*

# Reload systemd configuration
systemctl daemon-reload

journalctl

Purpose: Systemd journal viewing Usage: journalctl [options...] Dependencies: systemd

Examples

# Show all logs
journalctl

# Show logs for service
journalctl -u bootc-*

# Show recent logs
journalctl -n 100

# Follow logs
journalctl -f

# Show logs since time
journalctl --since "1 hour ago"

# Show logs with priority
journalctl -p err

Container Commands

podman

Purpose: Container runtime Usage: podman <subcommand> [options...] Dependencies: podman

Examples

# List containers
podman ps

# List images
podman images

# Pull image
podman pull quay.io/myorg/image:latest

# Run container
podman run -it image:latest

# Build image
podman build -t myimage:latest .

# Inspect image
podman inspect image:latest

docker

Purpose: Alternative container runtime Usage: docker <subcommand> [options...] Dependencies: docker

Examples

# List containers
docker ps

# List images
docker images

# Pull image
docker pull quay.io/myorg/image:latest

# Run container
docker run -it image:latest

# Build image
docker build -t myimage:latest .

Bootloader Commands

grub-mkconfig

Purpose: Generate GRUB configuration Usage: grub-mkconfig [options...] Dependencies: grub2

Examples

# Generate GRUB config
grub-mkconfig -o /boot/grub/grub.cfg

# Generate with specific output
grub-mkconfig -o /boot/grub2/grub.cfg

# Generate with verbose output
grub-mkconfig -v -o /boot/grub/grub.cfg

grub-install

Purpose: Install GRUB bootloader Usage: grub-install [options...] <device> Dependencies: grub2

Examples

# Install GRUB
grub-install /dev/sda

# Install with specific directory
grub-install --boot-directory=/boot /dev/sda

# Install with verbose output
grub-install -v /dev/sda

efibootmgr

Purpose: EFI boot manager Usage: efibootmgr [options...] Dependencies: efibootmgr

Examples

# List boot entries
efibootmgr

# Create boot entry
efibootmgr -c -d /dev/sda -p 1 -L "Bootc" -l /EFI/bootc/grubx64.efi

# Delete boot entry
efibootmgr -b 0000 -B

# Set boot order
efibootmgr -o 0000,0001,0002

Archive Commands

tar

Purpose: Archive operations Usage: tar [options...] <archive> [file...] Dependencies: tar

Examples

# Create archive
tar -cf archive.tar file1 file2

# Extract archive
tar -xf archive.tar

# List archive contents
tar -tf archive.tar

# Create compressed archive
tar -czf archive.tar.gz file1 file2

# Extract compressed archive
tar -xzf archive.tar.gz

gzip

Purpose: Compression Usage: gzip [options...] [file...] Dependencies: gzip

Examples

# Compress file
gzip file.txt

# Decompress file
gzip -d file.txt.gz

# Compress with custom level
gzip -9 file.txt

# Keep original file
gzip -k file.txt

Monitoring Commands

top

Purpose: Process monitoring Usage: top [options...] Dependencies: procps

Examples

# Show processes
top

# Show specific user
top -u username

# Show specific process
top -p 1234

# Show with custom delay
top -d 5

# Show with custom sort
top -o %CPU

htop

Purpose: Interactive process monitoring Usage: htop [options...] Dependencies: htop

Examples

# Show processes
htop

# Show specific user
htop -u username

# Show specific process
htop -p 1234

# Show with custom delay
htop -d 5

iotop

Purpose: I/O monitoring Usage: iotop [options...] Dependencies: iotop

Examples

# Show I/O usage
iotop

# Show only processes doing I/O
iotop -o

# Show with custom delay
iotop -d 5

# Show with custom refresh
iotop -n 10

Security Commands

openssl

Purpose: SSL/TLS operations Usage: openssl <command> [options...] Dependencies: openssl

Examples

# Generate private key
openssl genrsa -out key.pem 2048

# Generate certificate
openssl req -new -x509 -key key.pem -out cert.pem

# Verify certificate
openssl verify cert.pem

# Check certificate details
openssl x509 -in cert.pem -text -noout

# Generate hash
openssl dgst -sha256 file.txt

gpg

Purpose: GPG operations Usage: gpg [options...] Dependencies: gnupg

Examples

# Generate key pair
gpg --gen-key

# List keys
gpg --list-keys

# Sign file
gpg --sign file.txt

# Verify signature
gpg --verify file.txt.asc

# Encrypt file
gpg --encrypt file.txt

Development Commands

make

Purpose: Build automation Usage: make [target...] Dependencies: make

Examples

# Build project
make

# Clean build
make clean

# Install
make install

# Run tests
make test

# Update generated files
make update-generated

cargo

Purpose: Rust package manager Usage: cargo <subcommand> [options...] Dependencies: rust

Examples

# Build project
cargo build

# Run project
cargo run

# Run tests
cargo test

# Check code
cargo check

# Update dependencies
cargo update

git

Purpose: Version control Usage: git <subcommand> [options...] Dependencies: git

Examples

# Clone repository
git clone https://github.com/containers/bootc.git

# Check status
git status

# Add files
git add .

# Commit changes
git commit -m "message"

# Push changes
git push

This comprehensive reference covers all external commands used by the bootc exec-in-host-mount-namespace system, providing examples and usage patterns for each command.