Linux

--version
cat /etc/SuSE-release

--oracle sudo without password
vi /etc/sudoers
add
oracle ALL=(ALL) NOPASSWD:ALL

--FIND ENV FOR PMON AND TNS ONLY SHOWS FOR ORACLE USER
f=$(ps -ef | egrep 'pmon|tnslsnr' | grep -v grep | awk '{print $2}')
for i in $f
do
   p=$(ps eww $i)
   echo ''
   echo 'PROCESS:'
   ps -ef | grep $i | grep -v grep
   echo 'ENV: '
   echo $p | grep -o 'TNS_ADMIN=[^ ]*'
   echo $p | grep -o 'ORACLE_HOME=[^ ]*'
   echo ''
done  
 

--actual free-able memory for new application (new Oracle SID for example)
linux-p7fm:~ # free -m
                   total       used       free     shared    buffers     cached
Mem:          2516       2436         80          0          5        255 
-/+ buffers/cache:      2175        341 
Swap:         2047        406       1641
actual free-able memory =
341 ~= 80 (free ram) + (5 + 255) (FS cache)
Note:
Using that memory by application will work as Linux will reduce FS cache,
from other point of view that can impact performance as more i/o will 
be on the system

--How to enable ip for network adapter
ping xxx
Connect: network is unreachable
[root@grid2 ~]# vi /etc/sysconfig/network-scripts/*eth0
DEVICE="eth0"
BOOTPROTO=none
NM_CONTROLLED="yes"
ONBOOT="no" - replace by "yes" and reboot
TYPE="Ethernet"
UUID="c4a0e7f8-afe8-4e15-8fe7-a3b6c5eed4b6"
IPADDR=192.168.56.102
PREFIX=24
GATEWAY=192.168.56.1
DEFROUTE=yes
IPV4_FAILURE_FATAL=yes
IPV6INIT=no
NAME=eth0
HWADDR=08:00:27:D8:87:55