Kernels available in the archive

[Breno Leitao]

Hi,

I recently found that some of the kernel I am using disappear from the
archive, as in the exact version of it.

For example, I have a machine running kernel 3.13.0-43.72, and when I
try to download the source code, it is not available any more in the
repository. I am using the following command, that I got from [1]

  # apt-get source linux-image-$(uname -r)

And then I get:

  E: Failed to fetch http://archive.ubuntu.com/ubuntu/pool/main/l/linux/linux_3.13.0-43.72.dsc  404  Not Found [IP: 91.189.91.13 80]

Because the version 3.13.0-43.72 is not available anymore in the repo.

Should I move to the latest kernel before trying to download the source?
Isn't it possible to download the exact source code of the kernel I
have?

Thank you,
Breno

[1] https://wiki.ubuntu.com/Kernel/BuildYourOwnKernel