To start with linux security do the following:

  1. Check version of kernel
cd /var/log
less dmesg

The first line should give the kernel installed currently and this should match the installed version with any patches.
Also you could give the following command:
uname -a

Which would also give the installed version of the kernel
View the total amount of memory by:
grep -i mem /var/log/dmesg
Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-ShareAlike 3.0 License