bootc-docs/exec-in-host-mount-namespace/bootc-exec-in-host-mount-namespace-quick-reference.md

bootc exec-in-host-mount-namespace - Quick Reference

Command Summary

Command	Purpose	Usage
exec-in-host-mount-namespace	Execute command in host mount namespace	bootc exec-in-host-mount-namespace [ARGS]...

Quick Commands

Basic Operations

# 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 Operations

# Check host filesystem
bootc exec-in-host-mount-namespace df -h

# View host processes
bootc exec-in-host-mount-namespace ps aux

# Check host system status
bootc exec-in-host-mount-namespace systemctl status

Installation Operations

# Create directories in host filesystem
bootc exec-in-host-mount-namespace mkdir -p /var/lib/bootc

# Copy files to host filesystem
bootc exec-in-host-mount-namespace cp /source/file /host/destination/

# Set permissions
bootc exec-in-host-mount-namespace chmod 644 /host/file

Common Options

Option	Purpose	Example
--help	Show help	bootc exec-in-host-mount-namespace --help
--verbose	Verbose output	bootc exec-in-host-mount-namespace -v ls /
--quiet	Quiet output	bootc exec-in-host-mount-namespace -q ls /

Error Codes

Code	Meaning	Solution
1	General error	Check logs for details
2	Missing command	Provide command to execute
3	Namespace access error	Check /proc/1/ns/mnt exists
4	setns error	Run as root
5	Command not found	Use full path to command

Common Issues

Missing Command

# Error: Missing command
# Solution: Provide a command
bootc exec-in-host-mount-namespace ls /

# Or use a shell
bootc exec-in-host-mount-namespace /bin/bash

Namespace Access Error

# Error: open pid1 mountns: No such file or directory
# Solution: Check if /proc/1/ns/mnt exists
ls -la /proc/1/ns/mnt

# Run as root
sudo bootc exec-in-host-mount-namespace ls /

setns Error

# Error: setns: Operation not permitted
# Solution: Run as root
sudo bootc exec-in-host-mount-namespace ls /

# Check capabilities
getcap /usr/bin/bootc

Command Not Found

# Error: exec: command not found
# Solution: Use full path
bootc exec-in-host-mount-namespace /bin/ls /

# Check command availability
bootc exec-in-host-mount-namespace which ls

Environment Variables

Variable	Purpose	Default
RUST_LOG	Log level	info
BOOTC_DEBUG	Debug mode	false
BOOTC_CONFIG	Config file	/etc/bootc/config.toml

Configuration Files

File	Purpose	Location
Main config	Bootc configuration	/etc/bootc/config.toml
Namespace info	Namespace information	/proc/1/ns/mnt
Process info	Process information	/proc/self/ns/mnt

Log Files

File	Purpose	Location
System logs	System messages	/var/log/messages
Journal logs	Systemd journal	journalctl -u bootc-*
Bootc logs	Bootc specific	/var/log/bootc/

Performance Tips

Optimize Operations

# Check system load
uptime

# Check memory usage
free -h

# Check namespace overhead
time bootc exec-in-host-mount-namespace /bin/true
time /bin/true

Monitor System

# Check namespace availability
ls -la /proc/1/ns/mnt

# Check namespace differences
diff /proc/1/ns/mnt /proc/self/ns/mnt

# Check system performance
bootc exec-in-host-mount-namespace top -bn1 | head -20

Security Considerations

Root Privileges

• All exec-in-host-mount-namespace commands require root privileges
• Use sudo or switch to root user
• Check current user with whoami

Namespace Access

• Command accesses host mount namespace through /proc/1/ns/mnt
• Requires appropriate privileges for namespace switching
• Uses setns system call for namespace switching

Process Isolation

• Command executes in host mount namespace
• Current process is replaced with target command
• Provides access to host filesystem view

Best Practices

Regular Operations

• Use only when host mount namespace access is needed
• Check command availability before execution
• Implement proper error handling
• Monitor system performance

Development

• Use in container environments
• Test commands before production use
• Document procedures
• Monitor system health

Production

• Set up monitoring
• Configure alerts
• Regular testing
• Document procedures

Troubleshooting Steps

1. Check command availability

   bootc exec-in-host-mount-namespace which <command>
   

2. Check namespace availability

   ls -la /proc/1/ns/mnt
   

3. Check privileges

   whoami
   sudo bootc exec-in-host-mount-namespace <command>
   

4. Check logs

   journalctl -u bootc-* --since "1 hour ago"
   tail -f /var/log/bootc/main.log
   

5. Test command execution

   bootc exec-in-host-mount-namespace /bin/true
   

Quick Scripts

Health Check

#!/bin/bash
bootc exec-in-host-mount-namespace /bin/true && echo "System healthy"

Namespace Test

#!/bin/bash
bootc exec-in-host-mount-namespace ls / && echo "Namespace access OK"

Command Test

#!/bin/bash
bootc exec-in-host-mount-namespace which "$1" && echo "Command available"

System Check

#!/bin/bash
bootc exec-in-host-mount-namespace uname -a && echo "System check OK"

Integration Examples

Systemd Service

# Create service file
cat > /etc/systemd/system/bootc-exec-in-host-mount-namespace.service << EOF
[Unit]
Description=Bootc Exec in Host Mount Namespace Service
After=multi-user.target

[Service]
Type=oneshot
ExecStart=/usr/local/bin/bootc-exec-in-host-mount-namespace-script.sh
User=root
Group=root

[Install]
WantedBy=multi-user.target
EOF

# Enable service
systemctl daemon-reload
systemctl enable bootc-exec-in-host-mount-namespace.service

Cron Job

# Add to crontab
echo "0 2 * * * /usr/local/bin/bootc-exec-in-host-mount-namespace-maintenance.sh" | crontab -

Monitoring

# Check system health
if ! bootc exec-in-host-mount-namespace /bin/true > /dev/null 2>&1; then
    echo "WARNING: Exec-in-host-mount-namespace failed"
    # Send alert
fi

This quick reference provides essential information for using the bootc exec-in-host-mount-namespace system effectively.