Linux Bootmisc Script Reference

Overview

The bootmisc initialization script handles critical system startup tasks and filesystem preparation.

Core Functions

Login Management

# Prevent premature logins
touch /etc/nologin

# Setup user tracking
touch /var/run/utmp
chmod 664 /var/run/utmp

System Configuration

# Load kernel parameters
/sbin/sysctl -p /etc/sysctl.conf

# Update environment
/usr/sbin/env-update.sh

Filesystem Cleanup

# Clear stale files
rm -f /var/lock/*
rm -f /var/run/*
rm -rf /tmp/* /tmp/.*

# Preserve lock directory
touch /var/lock/.keep

X11 Setup

# Create X11 directories
mkdir -p /tmp/.X11-unix
mkdir -p /tmp/.ICE-unix
chown root:root /tmp/.X11-unix /tmp/.ICE-unix
chmod 1777 /tmp/.X11-unix /tmp/.ICE-unix

# SELinux context
restorecon -R /tmp/.X11-unix /tmp/.ICE-unix

Logging

# Save boot messages
dmesg > /var/log/dmesg

Configuration Files

• /etc/sysctl.conf: Kernel parameters
• /etc/env.d/*: Environment variables
• /etc/security/console.perms: PAM console permissions

Dependencies

• SELinux (optional, for restorecon)
• PAM (for console permissions)
• sysctl
• env-update

Common Issues

Troubleshooting

1. X11 socket errors:

ls -la /tmp/.X11-unix
restorecon -v /tmp/.X11-unix

2. Login issues:

ls -l /var/run/utmp
ls -l /etc/nologin

3. Environment problems:

env-update
source /etc/profile

Prevention

• Don’t remove /var/lock or /var/run
• Maintain correct permissions on /tmp
• Keep PAM properly configured