clear-log-ubuntu/README.md

# Clear Logfiles for Ubuntu 24.04 Server  
[![OS](https://img.shields.io/badge/ubuntu-24.04-E95420)](#)
[![Shell](https://img.shields.io/badge/shell-bash-121011)](#)
[![Feature](https://img.shields.io/badge/feature-log_cleanup-0078D7)](#)
[![License](https://img.shields.io/badge/License-MIT-green)](./LICENSE)

Install log cleanup and logfile reporting on Ubuntu 24.04 server.

Not a demo, not a quick hack.  
This script is built for production systems and safe unattended execution.

---

## Why this installer exists

Ubuntu systems accumulate rotated logfiles over time.  
While `logrotate` handles rotation, old rotated logs are not automatically removed, and custom or installer-generated logs can grow unnoticed.

Disk space is rarely the real problem.  
Operator clarity is.

An unmanaged `/var/log` directory becomes noisy over time and increases the risk of misreading timestamps or confusing old incidents with new ones during troubleshooting — especially under pressure.

In environments without centralized log storage, keeping `/var/log` clean ensures it remains a usable, live operational workspace.

---

## What this script does

✔ Scans `/var/log` recursively  
✔ Deletes classic rotated logfiles created by logrotate  
✔ Detects and reports large unrotated logfiles  
✔ Detects non-logrotate numeric logfiles (installer and debug logs)  
✔ Writes a full execution report to a logfile  
✔ Designed for unattended cron execution  

---

## What this script does NOT do

It won’t stop you from running the script without reading the documentation like there’s no tomorrow.  
Skip the README, and whatever happens next is your headache, not a bug report.

---

## 1. Download

```
git clone https://git.x-files.dk/system/clear-log-ubuntu.git
```

---

```
cd clear-log-ubuntu
```

---

## 2. Install

```
sudo cp clear-log-files /usr/local/sbin/
```

---

## Recommended first run

The script is published in dry-run mode by default so nothing gets deleted.

Run the script manually the first time.

```
sudo /usr/local/sbin/clear-log-files
```

Review the generated report in:

```
/var/log/clear-log-files.log
```

Once you are satisfied with the behavior, edit the script and set:

```
dryrun=false
```

Only then should the script be deployed via cron.

---

## Cron usage

Once verified, add a weekly cron job. This can quickly be done from the command line like this:

```
sudo tee /etc/cron.d/clear-log-files >/dev/null <<EOF
0 2 * * 5 root /usr/local/sbin/clear-log-files >/dev/null 2>&1

EOF
```

## Configuration

The two most important variables are defined at the top of the script.

```
dryrun=true
extended_cleanup=false
```

### dryrun

- `true`  
  Default. No files are removed. All actions are simulated and reported.

- `false`  
  Enables real cleanup. Intended for cron usage after verification.

### extended_cleanup

- `false`  
  Non-logrotate numeric logs are reported only (default and recommended).

- `true`  
  Non-logrotate numeric logs are deleted during real runs.

Deletion of extended logs requires both:
- `dryrun=false`
- `extended_cleanup=true`

This is intentional.

---

## Script output

Each run writes a full report to:

```
/var/log/clear-log-files.log
```

The report includes:
- which files were removed
- which files were reported only
- warnings about large active logfiles
- execution timestamp and configuration state

This makes audits and troubleshooting straightforward.

---

## Logfile cleanup policy

The script separates logfiles into three distinct classes.

### Classic rotated logs (auto-removed)

Examples:

```
auth.log.1
auth.log.2.gz
kern.log.4.gz
dpkg.log.1
```

---

### Extended rotated logs (reported only by default).

Examples:

```
subiquity-client-debug.log.1946
installer-info.log.1990
customapp.log.999
```

These files are not created by `logrotate`.

By default, they are detected and reported but not deleted. Setting extended_cleanup to true changes this.

---

### Large unrotated logs (warnings only)

Any active `.log` file exceeding the configured size threshold is reported as a warning no action is taken.  

---

### What this script will "NEVER" delete are:

Kernel logs and audit logs. These are allways kept for forensic needs. This is intentionally by design. 

---

## Configuration

The two most important variables are defined at the top of the script.

```
dryrun=true
extended_cleanup=false
```

### dryrun

- `true`  
  Default. No files are removed. All actions are simulated and reported.

- `false`  
  Enables real cleanup. Intended for cron usage after verification.

### extended_cleanup

- `false`  
  Non-logrotate numeric logs are reported only (default and recommended).

- `true`  
  Non-logrotate numeric logs are deleted during real runs.

Deletion of extended logs requires both:
- `dryrun=false`
- `extended_cleanup=true`

This is intentional.

---

## Script output

Each run writes a full report to:

```
/var/log/clear-log-files.log
```

The report includes:
- which files were removed
- which files were reported only
- warnings about large active logfiles
- execution timestamp and configuration state

This makes audits and troubleshooting straightforward.

---

### More Information

More guides and documentation can be found on [wiki.x-files.dk](https://wiki.x-files.dk)

---

### License

Licensed under the [MIT License](./LICENSE).