Linux

Check number of CPU’s

$cat /proc/cpuinfo

Check memory information

cat /proc/meminfo

Check swap

$swapon -s

Kernel parameter

#/sbin/sysctl -a
cat /etc/sysctl.conf

System error log

/var/log/messages

Nic configuration

ifconfig -a

Useful Links-

Linux file and related commands - http://www.oracle.com/technology/pub/articles/advanced-linux-commands/part1.html

Top,find and snice commands – http://www.oracle.com/technology/pub/articles/advanced-linux-commands/part2.html

free,vmstat,iostat and sar – http://www.oracle.com/technology/pub/articles/advanced-linux-commands/part3.html

ifconfig,netstat (network commands)  - http://www.oracle.com/technology/pub/articles/advanced-linux-commands/part4.html

cpio,tar and Oracle VM – http://www.oracle.com/technology/pub/articles/advanced-linux-commands/part5.html