This warning typically appears on systems using ASpeed AST2x00 series BMC controllers (common on ASRock server boards) when the kernel tries to load the ast display driver module. The ast_dp501_fw.bin is firmware for the DisplayPort controller.

For servers without graphical output requirements, this warning can be safely ignored because:

• The AST driver falls back to basic VGA mode without the firmware
• Console redirection via IPMI isn't affected
• No impact on server stability or performance

Option 1: Install the firmware package (recommended)

For Ubuntu 15.10, the firmware should be available in the linux-firmware package:

sudo apt-get update
sudo apt-get install --reinstall linux-firmware

Option 2: Manual firmware installation

If the package doesn't contain the firmware, download it manually:

wget https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git/plain/ast_dp501_fw.bin
sudo mkdir -p /lib/firmware/ast
sudo cp ast_dp501_fw.bin /lib/firmware/ast/
sudo update-initramfs -u

For completely headless servers, prevent the module from loading:

echo "blacklist ast" | sudo tee /etc/modprobe.d/blacklist-ast.conf
sudo update-initramfs -u

Check if the warning disappears after updates:

sudo update-initramfs -u -k all

For newer Ubuntu versions (18.04+), this firmware is included in the standard linux-firmware package. Consider upgrading if maintaining this server long-term.

When working with Ubuntu 15.10 Server on Asrock E3C226D2I motherboards, you might encounter this warning during kernel updates or initramfs regeneration:

root@fileserver:~# update-initramfs -u
update-initramfs: Generating /boot/initrd.img-4.2.0-27-generic
W: Possible missing firmware /lib/firmware/ast_dp501_fw.bin for module ast

This occurs because the system detects an Aspeed AST graphics controller (commonly used in server boards) but can't find the proper DisplayPort firmware.

For headless servers, this missing firmware typically has no operational impact since:

• No graphical output is required
• Remote management (like IPMI) uses separate hardware
• Console access works via serial or SSH

To eliminate the warning while maintaining system integrity:

# Create a dummy firmware file
sudo mkdir -p /lib/firmware
sudo touch /lib/firmware/ast_dp501_fw.bin

# Update initramfs to acknowledge the "found" firmware
sudo update-initramfs -u -k all

For a more robust solution in Debian-based systems:

# Install dummy firmware package
sudo apt-get install firmware-misc-nonfree

# Alternatively, blacklist the ast module
echo "blacklist ast" | sudo tee /etc/modprobe.d/blacklist-ast.conf
sudo update-initramfs -u

Prevent the module from loading by editing GRUB configuration:

# Edit GRUB configuration
sudo nano /etc/default/grub
# Append to GRUB_CMDLINE_LINUX_DEFAULT: "modprobe.blacklist=ast"
sudo update-grub

Confirm the solution worked by checking kernel messages:

dmesg | grep -i ast
# Should show either successful firmware load or module blacklisted

• Monitor for any unexpected behavior after changes
• Document the modification in your system configuration records
• Consider testing in staging before production deployment

The warning is harmless for server use, but these solutions provide cleaner system logs and eliminate potential confusion during maintenance.