Custom kernels with pv-grub

December 23, 2008 1:12 pm

It’s now possible to boot custom kernels and even alternate operating systems under your Linode instance by the use of pv-grub — a port of the GRUB bootloader into the Xen mini-os kernel.  Essentially, your Linode boots into the pv-grub kernel, looks for your menu.lst and associated kernel files, and then executes your kernel.

Although this feature sounds pretty neat, it’s definitely for you tweakers out there.  We won’t be providing any support for custom configurations or alternate operating systems beyond supporting pv-grub itself.  We still recommend that you run our kernels, unless you have some very specific needs or just want to mess around.

There’s a wiki article to get you started, and even another article that outlines freeing the BSD on Linode.

9 Responses

  1. […] Posted on December 24, 2008 – 8:19am I reckon the logo on Linode Wiki needs a change. Via Linode’s latest blog post, it is now possible to roll your own operating system with Linode’s pv-grub support. […]

  2. […] Linode Blog » Custom kernels with pv-grubThis would be enough to run selinux or app-armor on linode now. […]

  3. How stable is that? Is it stable enough for a production system?

  4. How stable is pv_grub? pv_grub boots your own kernel, and then it’s done, so it has little to do with stability. I think the question is: how stable the custom kernel that you’ve provided is.

  5. Well, the reason I’m asking is because I have experienced stability problems with vmware’s CONFIG_VMI kernel option in an otherwise very stable kernel.

  6. In case anyone else is thinking of going down the same path I tried, the CentOS 5.2 kernel-xen package wasn’t built with all of the options specified on the linked wiki page, so it won’t work with pv-grub without a custom compile (unless I did something wrong).

  7. That’s great news. I’m going to play around with this a bit.

    I suspect I won’t be able to get it to do what I ultimately want: boot an OpenSolaris (2008.11) instance. I’ve been able to get OpenSolaris running well on XenServer, but I can’t use pv_grub. The root filesystem is ZFS, so the script can’t reach in and pull out the menu.lst file unless it knows how to deal with that FS.

    In my experience, I have to use the PV-args and PV-kernel parameters in XenServer to make it work (see my website for details). If there’s a way that you can expose those configuration items, that would be awesome.

  8. I recently switched to Linode because of this. I’ve been running Gentoo with my own custom kernel for a few days now and it’s working great. This feature is awesome.

  9. I’m in the process of switching from slicehost because of this.

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