Our legacy software only works on a v2.6 kernel and the new KVM nodes don't offer that kernel. I know that Linode wants everyone to eventually move over, but it's difficult when they don't provide comparable kernels. We've asked for the config they used to build the 2.6, so we can try to build a kernel from scratch, but Linode has refused to provide it. We feel we're on a clock to get these nodes migrated to KVM, with no easy path to do so.

Any one know how to build a custom kernel for KVM? We have no idea where to start with it, since we don't know what needs to be built into it to work in the Linode environment -- that's why we've always used the Linode-provided kernels.

The config should be available in /proc/config.gz on a running system. The exact kernel config settings you need are in the Linode KVM Reference doc: https://www.linode.com/docs/platform/kv ... figuration

That said, you do have more flexibility to run custom environments with KVM. Depending on what distribution you're running, you might want to try using their stock kernel and it could just work. You can also try switching to full virtualization mode.

_________________

/* TODO: need to add signature to posts */

We did try running on the new system and had strange software behavior that led us to believe it was kernel-related. As to running in full virtualization mode, we didn't try that, but since the issue were with the software crashing and nothing related to drivers, we assumed it was the kernel.

In any case, thanks very much for the information -- this gives us a good place to start.

Can you clarify why you feel this is the case?

- Les