How to setup VIP (Virtual IP) in a DG setup

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How to start databases in a DG setup

Scenario : Power outage at your data center brought down the databases in the DG configuration.

Solution : Start up the primary database
SQL> startup
: startup mount the standby database
SQL> startup mount

Login to Primary node and start dgmgrl
DGMGRL> connect sys/password
DGMGRL> enable configuration;
DGMGRL> enable fast_start failover;
DGMGRL> show configuration;

It should show you the primary database and physical standby database

Some Important Linux/Unix Commands

How to find bit level in Unix
$ isainfo -kv

In Linux
$ uname -a
gives you OS, version and bit level.

Find out KDE Desktop version:
konqueror --version

Find out Gnome Desktop version:
gnome-panel --version

Find out Mozilla browser version:
mozilla --version

Find out Firefox browser version:
firefox --version

Find out current Language:
set | egrep '^(LANG|LC_)'

Find out disk space usage:
df -h

Find/Estimate file space usage:
du -h

Find out version of Linux glibc:
ls -l /lib/libc-*.so /lib/libc.so*

Find out user limits:
ulimit -a

Find out installed device drivers (modules)
lsmod

Find out information about an X server:
xdpyinfo
It can find out:
• Name of display:
• Version number
• Vendor name (such as The XFree86 Project)
• Vendor release number
• And XFree86 version number

Find out information about Linux CPU
cat /proc/cpuinfo

Find out information about Linux Memory
cat /proc/meminfo
OR
free -m
OR
free -g

Find out user shell name:
ps -p $$ | tail -1 | awk '{ print $4 }'

Dump Linux kernel variables
/sbin/sysctl -a

Find out running Linux kernel version:
uname -mrs
uname -a
cat /proc/version

Dump or display memory information and swap information:
free -m

Network card and IP address information:
ifconfig -a
ifconfig -a|less

Debian / Ubuntu Linux network configuration file (all interface eth0,eth1,…ethN)
more /etc/network/interfaces
Redhat / CentOS / Fedora Linux network configuration file (eth0)
more /etc/sysconfig/network-scripts/ifcfg-eth0
Note replace eth1 for 2nd network card and so on.

Display routing information
route -n
route

Display list of all open ports
netstat -tulpn

View login related logs
tail -f /var/log/secure
vi /var/log/secure
grep 'something' /var/log/secure
View mail server related logs
tail -f /var/log/maillog
vi /var/log/maillog
grep 'something' /var/log/maillog

Find how long the system has been running
uname
w

Show who is logged on and what they are doing
w
who

Display list of tasks
top

Display all running process
ps aux
ps aux | grep process-name

Display list of all installed software on Redhat / CentOS / Fedora
rpm -qa
rpm -qa | grep 'software-name'
rpm -qa | less

Display list of all installed software on Debian / Ubuntu
dpkg --list

Once information collected it can be easily send as an email to help desk. You can use all above command to gathers information about a remote Linux system over secure ssh session (see related functions that gathers up information about a Linux and FreeBSD system). Best part is all above commands runs in non privileged