I need to install a non-PAE kernel for a 64-bit machine that supports PAE. 32-bit 12.04 currently comes with a PAE kernel but I need to get a non-PAE kernel. An older version of Ubuntu is also acceptable as long as it runs in 32-bit mode.
Ubuntu – How to install a non-PAE kernel on PAE-enabled hardware for Ubuntu 12.04
12.04kernelpae
Related Solutions
Simple: To support vast quantities of RAM in a 32bit environment.
Lots of people were installing the (then) recommended 32bit install and wondering why their new computers with 4 and even 8GB of RAM were only showing 2-3GB. By using the PAE kernel, the vast majority of that RAM is now addressable and usable.
This is fine for people who have computers built this century. To get a computer that doesn't have 32bit PAE support, we need a really old computer. We're talking PII/Geode level old, but also Pentium M machines like lots of Thinkpads.
These are computers that should be thrown into the sun. They are far below what people throw out and much better machines can be had for almost nothing on Ebay and the like.
There's an added side-effect of PAE that I've only just become aware of: NX. In 64bit mode all users get NX (No eXecute) which allows the system to separate out storage RAM from process RAM. This allows an application to suffer a buffer overflow without then being able to stuff a ton of malicious executable code in RAM and run it.
That's a obviously massive simplification but to further answer the question: it makes the computer more secure too.
And what's more to appease the super-low-end users the defaults for Lubuntu and Xubuntu will be a non-PAE kernel.
- https://bugs.launchpad.net/ubuntu-cdimage/+bug/955009
- https://bugs.launchpad.net/ubuntu-cdimage/+bug/958866
If you are on a lower-end computer, chances are you won't want Unity eating up the few remaining CPU cycles you have left, so they're a much saner starting point anyway.
On VirtualBox Manager, open your virtual machine configuration then select System on the left side and open the Processor tab. Be sure that Enable PAE/NX is checked.
For commandline
VBoxManage modifyvm <VM_name> --pae on
Best Answer
It's as simple as doing this on your existing 32-bit 12.04 installation:
sudo apt-get install linux-image-genericfollowed by a this to remove the PAE kernel (so the system boots from the non-PAE by default):
sudo apt-get remove linux-image-generic-paeGRUB_HIDDENlines in/etc/default/gruband runsudo update-grubto display the grub menu upon boot, from which you can select the kernel to use.If you want to install a non-PAE kernel as part of a new installation, start with Xubuntu or Lubuntu 12.04 32-bit, both of which come with the non-PAE kernel. Once running, you can run
sudo apt-get install ubuntu-desktopto get the full Unity desktop experience.In general, the two common kernel suffixes for 12.04 are:
-generic(non-PAE for 32-bit; standard for 64-bit)-generic-pae(PAE and default for 32-bit only)