Safe interactive log cleanup script

 You can use a safe interactive log cleanup script that:

1. Scans /var/log for the largest files.

2. Shows their sizes.

3. Asks for confirmation before clearing each file.

4. Clears only files you approve.

5. Keeps the log files in place, so services can continue writing to them.

Script: cleanup_logs.sh

###################################################




#!/bin/bash

LOG_DIR="/var/log"

MIN_SIZE="+100M"

if [[ $EUID -ne 0 ]]; then

    echo "Please run this script as root."

    exit 1

fi

echo "========== Disk Usage Before =========="

df -h "$LOG_DIR"

du -sh "$LOG_DIR"

echo

echo "Scanning log files larger than 100 MB..."

echo

find "$LOG_DIR" -type f -size "$MIN_SIZE" -print0 |

while IFS= read -r -d '' file; do

    # Skip symlinks

    [[ -L "$file" ]] && continue

    size=$(du -h "$file" | cut -f1)

    echo "--------------------------------------"

    echo "File : $file"

    echo "Size : $size"

    read -r -p "Clear this file? (yes/no): " answer </dev/tty

    if [[ "$answer" == "yes" ]]; then

        if truncate -s 0 -- "$file"; then

            echo "CLEARED: $file"

        else

            echo "FAILED: $file"

        fi

    else

        echo "SKIPPED: $file"

    fi

done

echo

echo "========== Disk Usage After =========="

df -h "$LOG_DIR"

du -sh "$LOG_DIR"

echo "Cleanup completed."


#######################################

How to run

Save the script:

vi /root/cleanup_logs.sh

Make it executable:

chmod +x /root/cleanup_logs.sh

Run:

/root/cleanup_logs.sh

Example output

========== Disk Usage Before ==========
45G    /var/log

Scanning log files larger than 100 MB...

--------------------------------------
File : /var/log/messages
Size : 28G
Clear this file? (yes/no): yes
CLEARED: /var/log/messages

--------------------------------------
File : /var/log/secure
Size : 9G
Clear this file? (yes/no): no
SKIPPED: /var/log/secure

--------------------------------------
File : /var/log/httpd/access_log
Size : 850M
Clear this file? (yes/no): no
SKIPPED: /var/log/httpd/access_log

========== Disk Usage After ==========
17G    /var/log
Cleanup completed.

Important safety precautions

The script clears file contents permanently, not just old log entries. In particular, audit logs, security logs, and application logs may be needed for troubleshooting, retention requirements, or investigations.

For production servers, I recommend reviewing files first and using logrotate or journalctl --vacuum-size for managed logs where appropriate. This script requires typing the full word yes for every file; anything else skips it.