topic Re: how to know the kernel features are enabled or disabled in Operating System - Linux

how to know the kernel features are enabled or disabled

Ming Zhao — Mon, 05 Jul 2004 21:14:03 GMT

Hi,

I am working on a RHEL3.0 without source code installed. Application team asked me to check if some kernel features are enabled:
COFNIG_NET
CONFIG_SYSVIPC
CONFIG_BINFMT_ELF
etc..

How to know if they are enabled or disabled.

Thanks,

Re: how to know the kernel features are enabled or disabled

Stuart Browne — Mon, 05 Jul 2004 22:39:02 GMT

Short of viewing the compiled-in '.config', (see /boot/config-2.4.xxxxx) some of them can be sorta difficult to figure out.

Short answers for the 3 listed:

If you have networking (at all), then CONFIG_NET is configured in.

If you can run most executables, CONFIG_BINFMT_ELF is configured in.

CONFIG_SYSVIPC will be compiled in, as it provides compatability with previous versions of SYS V IPC (Inter-Process communications). It's highly unlikely this one isn't compiled in.

Re: how to know the kernel features are enabled or disabled

Muthukumar_5 — Tue, 06 Jul 2004 01:24:53 GMT

Hai,

Kernel configuration settings are updated in the .config file. Features enablement uses "y" "n" or "m". Where

y - it is enabled
n - it is not enabled
m - modularised one

By default,

COFNIG_NET
CONFIG_SYSVIPC
CONFIG_BINFMT_ELF options are enabled.

Regards,
Muthukumar.

Re: how to know the kernel features are enabled or disabled

Jan Sladky — Tue, 06 Jul 2004 02:31:33 GMT

hi Ming,

perhaps "sysctl -a" will also be little usefull for your purposes, for more info see man sysctl

Hope this will help you

br Jan

Re: how to know the kernel features are enabled or disabled

Muthukumar_5 — Tue, 06 Jul 2004 03:56:43 GMT

Hai,

sysctl will be used to get the system control configuration settings. We can not ge t the kernel parameters with that.

.config file we be the source to know this. Default kernel's config will be located at /usr/src/linux-2.x.x/configs directory.
We can identify the kernel type and it's related .config file from grub loader or lilo loader.

Regards,
Muthukumar.

Re: how to know the kernel features are enabled or disabled

Ming Zhao — Tue, 06 Jul 2004 08:03:03 GMT

Thanks everybody!