Fixing Disk Space Issues

Running out of disk space is a common issue that can lead to several problems like performance degradation, inability to write new data, and service outages. This guide provides a set of guidelines to help you diagnose and resolve disk space issues on Ubuntu and AWS EC2 servers.

Preliminaries

Before proceeding, make sure you have:

SSH access to the server facing disk space issues.
Necessary permissions to delete or modify files and directories.
Backups of critical data, just in case.

Diagnostics

For Any Server

After SSHing into a server, run the following commands to identify disk space usage:

Initial Diagnostic
Terminal window
```
df -h
```
Be cautious if the Use% column shows over 90% for any partitions.
Detailed Directory Info
Terminal window
```
ls -lh /path/to/directory
```

This command provides detailed information about a directory’s child files and folders, formatted in a more human-readable way (-h).

For Ubuntu Specific

Check APT Cache Size: Ubuntu keeps a cache of downloaded updates, which can grow over time.
Terminal window
```
du -sh /var/cache/apt/archives
```

For AWS EC2 Instances

Check EBS Volume Details: Login to the AWS Management Console, identify the EC2 instance, and look for the details of the Root and block devices.

Remediation Steps

For Any Server

Remove Unnecessary Files/Directories: Based on the diagnostic info, try to remove any large or unnecessary files.
Terminal window
```
rm -r /path/to/unnecessary/files_or_directories
```

For Ubuntu Specific

Clean the APT Cache
Terminal window
```
sudo apt-get clean
```
Remove Old Kernels
Terminal window
```
sudo apt-get autoremove --purge
```

Uninstall Unused Apps

sudo apt-get remove package-name1 package-name2
sudo apt-get autoremove

Use System Cleaner (BleachBit)
- Install BleachBit from the Ubuntu Software Center.
- Run the app as root and choose files/directories to clean.

Keep the System Updated

sudo apt-get update && sudo apt-get upgrade

For AWS EC2 Instances

Phase 1: Prepare EBS Blocks

Login to the AWS Management Console.
Identify the EC2 instance(s) you need to extend.
Click on the EBS ID (vol-xxxx) to modify the EBS volume and set a new size.

Phase 2: Update Linux Servers

SSH into the EC2 instance.
Determine the block name and partition:
Terminal window
```
lsblk
```
Check existing disk space:
Terminal window
```
df -h
```

Run the resize commands:

growpart /dev/xvda 1
resize2fs /dev/xvda1

Confirm that disk space has increased:
Terminal window
```
df -h
```

Next Steps

If the issue persists, consider increasing the server size.
Keep monitoring disk usage to avoid future space issues.