Today the amount of data is increasing at an alarming rate
and backing it up has become a major challenge for system administrators. As a
result, the backup setup requirements have changed. Organizations now need
backup solutions that can scale up as their data grows. They can't depend upon
a solution that limits itself to single servers. That's where network backup
solutions come into play. This is a new trend in the backup industry, and offers
several benefits. For one, it improves the manageability of your entire backup
setup, since you're no oscillating between different servers to backup their
data. Everything's done over the network, including the management. Two, it
automates some of the tasks that were earlier done manually. These give your
backup administrators time to attend to other strategic issues. However, one
needs to do quite a bit of planning before implementing such a solution. Here,
we'll start off by helping you plan your backup strategy for network backup
and then take you through a sample implementation of the same.
Planning backups
The first step in this is of course to analyze your organizational data. Analyze
the type of data that you want to backup, how much data do you want to backup,
and how much is your data expected to grow in the future.
How much time does your current backup take, and how much
do you expect to reduce it by when it moves on the network. Next step is to
decide which business data is more important to your company. One possible
categorization of the value of data in your organization can be as follows:
Extremely Important Data: Identify data without
which your organization can't function. This would include things like orders
details, unpaid bills, proposals under negotiation, account statements of the
clients, salary information, etc.
Moderately important: Data that is critical, but can
be rebuilt with time and from other sources as well. This would include other
accounting data and HR information, central database.
Lesser Important: This would be departmental data.
Do the network backup from clients only during off-peak hours, |
Unimportant: Personal data of users (Pictures, MP3s,
videos, etc) is unimportant from an organization's point of view.
Backup Scenarios
Once you've categorized the data, you will have a clear idea of just how
much data needs to be backed up. Based on this, the next step is to look at the
various types of backup scenarios that are possible. Let's look at some of
them.
Server backup
This is the oldest and simplest of all backup scenarios, and is applicable
to departmental backups or small businesses. In this, all users have to
store their official data on servers and not on their personal machines.
You would then install a tape drive on the server and
follow the usual routine of backing up the data to tape. Since all the important
data is lying on the server, you don't really need to worry about the clients.
Even if they lose data, it can be retrieved from tapes.
The real challenge is in ensuring that users do use the
server for storing all their data. It also means that the traffic on the servers
will be quite high, so their configuration must be able to handle the load. The
challenge here would be to backup the users' email. That's where the next
level comes into play.
Large network backup
Today, it is normal for desktop systems to have 40-80 GB hard drives, and
users store most of their data to it. For medium to large enterprise networks,
which have a sizable number of such clients, following the usual server based
backup routine is not feasible. At the backend also, the number of servers has
also increased in these organizations. Therefore, it can become quite a
nightmare to put a tape drive on each server and backup data from it. At this
stage, you must consider going for network backup, which would create a separate
backup server to collect data from all the other servers and clients.
So a server connected to the backup devices would take the
backup from the other machines (clients/ servers) with the help of backup
agents, which are running on machines that need to be backed up.
Configure Netbackup 6.0 using a user-friendly wizard, which makes the configuration easy |
Personal backups
This is a typical environment for 5-20 users, where no central file server
is used. In this case, the backup has to be done on each machine using a common
shared device or even individual backup devices. You can even use a CD or
DVD-writer for this purpose, though given today's larger hard disks, you would
have to use quite a large number of CDs if you want to back up full hard disks
every time. Therefore you can use DVD instead of CDs, which these days have
become quite affordable. Whichever of the above you decide to choose, the
machines to be backed up, as well as the applications, the files and the folders
have to be identified first.
When to backup
Backup is a resource hungry process, which stresses both your systems and
your network. Typically you do not backup when the network is being used for
regular office work, because the data flow over the network for backup will slow
down the regular office work drastically. The usual option for doing back up is
to choose a time when the rest of the office is not working such as lunchtime or
after office hours, or even week ends. Everyone wants to back up at the least
time, but faster backup media and drives cost more than slower solutions.
Therefore, full backups should be done on weekends when
there is no user load and the backup window is about 24-36 hrs. Incremental
backups can be done on weekdays, after office hours with a backup window of 3-12
hrs. This is done by the backup software itself if you set your backup operation
on incremental mode. Here, the size of the data would be small compared to full
backup. Thus it takes lesser time too.
How to do a network backup
In order to demonstrate how network backup is setup, we took a product of
this class and deployed it. This was the Symantec NetBackup 6.0, which is an
enterprise class network backup software.
It's very easy to setup and lets you manage all backup
operations from a single point. It allows you to take backups from both server
and desktop class machines and a host of Operating Systems. These include
various versions of Windows, UNIX, Linux, and NetWare. It supports all types of
tape libraries and disk based backup devices. The administrator can initiate
backups remotely, and even setup periodic or calendar-based backup schedules to
perform automatic, unattended backups for clients across the network.
This can be useful to perform backups when the network is
free, such as lunch-time, after-office hours, weekends, etc. You can take full
backup from all the servers and clients or do incremental (backing up only the
files that have changed since the last backups. Everything in NetBackup can be
administered through policies. For instance, you can define a policy, which will
determine whether a user is allowed to perform restore operations or not. The
main component of NetBackup is the Media Manager, which manages all the storage
devices. To check its functionality, we used it to control backup operations on
a tape library.
The Server Setup
The server that connects to the tape library has to be made as the Master
Server. For this, you have to install the NetBackup server 6.0 on that machine.
The software has three install options, called the Master Server, Media Server,
and Remote Administration Console. Select the first option. The installation
will prompt you to enter your media server's name, which by default is the
same as the machine's name. Don't change it. Once installed, you need to
install the Veritas device drivers, which will automatically install the drivers
for the connected tape library.
Next, the Master Server has to be configured to take the
backup jobs from clients and servers running on your network, and back them up
to the tape library. For this, the Removable Media Service or RMS has to be
disabled from services. After that, run the NetBackup Administration Console
from the Start Menu. Before starting it, you will be asked to enter the
server's name where you have installed the Master Server. In our case, it was
on the same machine, so we use used 'localhost' instead of the server's
name. Then left pane of the console contains a node for each major area of
NetBackup administration. Clicking a node displays information related to that
node in the Details pane on the right. NetBackup is very easy to setup using its
'Get Started' wizard.
From the right pane, select 'Getting Started'. This
wizard is used if you are configuring NetBackup for the first time. It will take
you through the essential steps and other wizards to get you up and running with
a working NetBackup configuration. It includes wizards to configure your storage
devices, volumes, configure Catalog Backup, create backup policies, and
configure storage devices.
Backup process is initiated automatically from the master server according to defined policies |
Device setup
There's a device configuration wizard to guide you through the entire
process of configuring a device and storage unit connected to the master server.
It automatically detects the connected tape library and fetches the drive
parameters, which is required by the master server to manage the tapes
inventory. The next part is to configure volumes from the backup data; a volume
pool is created to add volumes that the administrator can assign to explicit
backup policies or schedules. The Volume Configuration Wizard guides you through
the entire process and configuring removable media accordingly. Another
important part of NetBackup is configuring catalog backup. It helps you set up
your catalog backups, which are essential for recovering your data in case of a
server failure or crash. This basically creates an index file, which helps the
Master Server recover data quickly from the storage media.
Backup policy
This wizard lets you create automated backup policies, which allow you to
take scheduled backups of your connected machines on tapes. The Backup Policy
wizard configuration wizard adds a backup policy to your configuration. Besides
these, there are several other useful wizards in NetBackup. There's the Import
Images wizard, which can import backups that have expired, backups from another
NetBackup server, or backups that were written by Backup Exec for Windows. It
imports images in a two-part process. First it creates a list of expired catalog
entries for the backups on the imported volume. No actual import occurs in this
process. In the next process images are selected from the expired list of image
generated from process one and then you can import the Netbackup. There's also
a wizard to configure shared devices. This let's you configure NetBackup to
use shared drives or reconfigure an existing shared drive. There's another
wizard for recovering the catalog, which lets you recover data from the backup
media when disaster strikes.
Client Setup
NetBackup has client agents for all types of clients including Windows, Unix,
Solaris and even 64-bit
OSs
. You need to install it on all the clients to backup data remotely from them.
The backup process can be initiated directly from the client, or you can setup a
schedule backup policy on the Master Server so that NetBackup can automatically
take backup of that machine on the tape periodically. If you want to take
backups from the clients directly, then lunch “Backup, Archive and Restore”
program and select the data that you want to take backup and then click the
backup button. This will open a backup options window; here select the master
server, where you Netbackup server and backup devices are connected. Finally
click 'Start' button to initiate the backup process.
Sanjay Majumder