linux 32 bit or 64 bit

[manoj.linux]

Hi,

I want to know how to find out wheather Linux is 32 bit or 64 bit os?

Regards,

Manoj

[MikeTbob]

Usually when you download a 64 bit ISO, it will have a name with 64 in the title, like this
http://ubuntu.univ-nantes.fr/ubuntu-...ktop-amd64.iso

[L4Linux]

Open a terminal and type:

uname -a

Mine shows:

Linux ubuntu 2.6.27-11-generic #1 SMP Thu Jan 29 19:24:39 UTC 2009 i686 GNU/Linux

This i686 means it is 32bit. 386, 586 and 686 all mean 32bit.
If yours is 64bit, it will say so in the output of uname -a.

[vonbiber]

If you have the kernel sources and your machine supports the 64-bit
architecture and your current kernel is 32-bit you can rebuild it so as
it is 64-bit
In the config file, you can see it
# zcat /proc/config.gz > ~/config
# less config

you should see lines like
# CONFIG_64BIT is not set
CONFIG_x86_32=y
# CONFIG_x86_64 is not set

you can change it by first reconfiguring it:
cd /usr/src/linux-$(uname -r)
# make menuconfig

and then rebuilding it