When working with Ubuntu 8.04 LTS (Hardy Heron), you'll often encounter this scenario:

$ sudo apt-get upgrade
Reading package lists... Done
The following packages have been kept back:
  apache2 mysql-server php5
0 upgraded, 0 newly installed, 0 to remove and 3 not upgraded.

This indicates that while updates exist for these packages, they're being held back due to dependency constraints that apt-get upgrade won't automatically resolve.

The key differences between these commands:

# Standard upgrade (safe)
sudo apt-get update && sudo apt-get upgrade

# Distribution upgrade (more aggressive)
sudo apt-get update && sudo apt-get dist-upgrade

• upgrade: Only upgrades existing packages without installing/removing dependencies
• dist-upgrade: Smartly handles dependency changes, may add/remove packages

For your specific concern about Ubuntu 8.04 LTS:

# Check current release
lsb_release -a

Using dist-upgrade won't automatically upgrade you to 8.10 (Intrepid Ibex) because:

1. LTS releases have separate repositories
2. You'd need to explicitly change your /etc/apt/sources.list
3. LTS-to-LTS upgrades require different commands (do-release-upgrade)

Before running dist-upgrade on a production server:

# 1. Check what would change
sudo apt-get -s dist-upgrade

# 2. Create a snapshot if using virtualization
# 3. Check for held packages
apt-mark showhold

# 4. Review important config files
sudo apt-get -o Debug::pkgProblemResolver=yes dist-upgrade

Here's how we recently handled a kept-back MySQL package:

# Initial state
$ apt-cache policy mysql-server
mysql-server:
  Installed: 5.0.51a-3ubuntu5.4
  Candidate: 5.0.51a-3ubuntu5.6
  Version table:
     5.0.51a-3ubuntu5.6 0
        500 http://archive.ubuntu.com hardy-updates/main Packages
        500 http://security.ubuntu.com hardy-security/main Packages
 *** 5.0.51a-3ubuntu5.4 0
        100 /var/lib/dpkg/status

# Safe upgrade approach
$ sudo apt-get install mysql-server=5.0.51a-3ubuntu5.6

Instead of immediately jumping to dist-upgrade, consider:

# Option 1: Install specific versions
sudo apt-get install package=version

# Option 2: Use aptitude (often handles dependencies better)
sudo aptitude safe-upgrade

# Option 3: Temporary ignore dependencies
sudo apt-get -o Dpkg::Options::="--force-overwrite" upgrade

Always verify after major updates:

# Check services
sudo service --status-all

# Verify config files
sudo dpkg --verify

# Review changed files
sudo apt-get install debian-goodies
sudo debchanges -a

When managing an Ubuntu 8.04 LTS server, you might encounter this common scenario:

$ sudo apt-get upgrade
Reading package lists... Done
The following packages have been kept back:
  libapache2-mod-php5 mysql-server-5.0
0 upgraded, 0 newly installed, 0 to remove and 2 not upgraded.

The key distinction between regular upgrades and dist-upgrade:

• apt-get upgrade: Updates existing packages without changing distribution version
• apt-get dist-upgrade: Handles dependencies and may install/remove packages

For a controlled approach:

# First check what would change
$ sudo apt-get -s dist-upgrade

# Then perform the actual upgrade
$ sudo apt-get dist-upgrade

For mission-critical systems:

# Create a snapshot of current package states
$ sudo apt-get install debconf-utils
$ sudo debconf-get-selections > debconf-selections-backup.txt
$ dpkg --get-selections > dpkg-selections-backup.txt

# Review changed dependencies
$ apt-cache policy [package-name]
$ apt-cache depends [package-name]

Essential checks after upgrading kept-back packages:

# Verify successful upgrades
$ dpkg -l | grep -i [package-name]

# Check service status
$ sudo service --status-all

# Review config file changes
$ sudo dpkg --configure -a