Ensuring Business Continuity in a SAP Environment
Disaster Recovery is about protecting data. Datacenter availability
involves protecting both the data and the application.
Planned or unplanned, downtime signals the certainty of real,
quantifiable, losses for businesses that rely on SAP applications. After all,
for companies around the globe, SAP applications are fundamental to their daily
operations. Any disruption in the critical business processes to which SAP applications
are linked could result in the loss of millions of dollars or more every hour.
Research suggests that many companies experiencing a major disaster are at risk
of going out of business within the next two months.
As a result, a growing number of organisations are recognising the importance
of developing a business continuity plan that protects their SAP environment.
To be effective, this plan must address the three primary areas of concern within
SAPavailability, manageability, and support for data centre availability
through a combination of end-to-end technology solutions and practices.
Its important to understand what is being implied when we say datacentre
availability in the context of this article. Disaster Recovery (DR) is about
protecting data. Typically companies back up their data to tapes or disk
and recover it to a back up server. This may also entail replicating data
from one storage system to a storage system in another location.
Datacenter availability is the protection of both the data and the application
itself. The key differentiator is that datacenter availability recognises
the importance of keeping an organisations applications up and running and protects
the application by allowing the application to be failed over from one
server to another server regardless of whether or not the server is part of
a local, stretch or remote cluster.
SAP applications must be available not only on a daily basis but they must also
be protected against loss of service and data resulting from a disaster or widespread,
However, the SAP environment is highly complex, with multiple services deployed
across multiple servers for an SAP application instance. Each servicefrom
the messaging service to the enqueue service, database instance, and Network
File System (NFS) or CIFS servicesrepresents a potential single point
of failure. Redundancy must be built at the component level for each layer,
which, in turn, increases the complexity and challenges of managing the environment.
Also, while maintaining an alternative location that is geographically
separate from the primary production environment is an effective business continuity
option, it can also be costly. Traditional SAP recovery solutions often require
that identical, expensive hardware be deployed at all locations. Secondary sites
often must also be maintained at the same update and patch levels as the primary
Switching an application to the disaster recovery site is also cumbersome and
challenging, often requiring IT to move tapes and personnel from one facility
to another, rebuild servers, load operating systems, and back up software. Also,
at the secondary site, IT personnel must be available to manually walk through
complicated, urgent, but potentially error-prone procedures for restarting interdependent
Available, Manageable, Recoverable
In an SAP environment, ensuring business continuity starts locally. For example,
local redundancy can be achieved by utilising a single interface for starting,
stopping, monitoring, and maintaining SAP application services. Change can be
managed by proactively moving application services to enable dynamic maintenance
Local availability can be improved with automated, application-specific monitoring
and failover when problems do occur and fast reconfiguration when the problem
is resolved. Local clustering and the virtualisation of critical services can
enable the organisation to consolidate servers, make better use of existing
resources, and protect against potential single points of failure. And policy-based
storage management can significantly improve storage utilisation and enhance
Once the local availability infrastructure is in place, organisations can then
leverage their existing architecture and build an alternative site for remote
datacenter availability. Adding global clustering and data replication enables
organisations to quickly and accurately switch over an entire SAP application
between geographically dispersed datacenters.
A growing number of SAP availability solutions eliminate the cost concerns typically
associated with having duplicate data centers. For example, solutions that do
not require secondary sites to be identical in computing resources to primary
sites obviate the need for organisations to invest in expensive, matching servers.
Solutions that do not require secondary
sites to be identical in computing resources to primary sites obviate
the need for organisations to invest in expensive, matching servers
Moreover, organisations can realise significant cost savings by using their
secondary site for other, less essential processes and then simply shut them
down before bringing more critical processes online in the event of a disaster.
Global clustering capabilities link together clusters from geographically separate
sites and connect SAP applications across them. By providing SAP application
failover to a remote site, this capability helps ensure service level protection
against the failure of an entire site.
The most advanced global clustering solutions continuously monitor and communicate
SAP application events between clusters, thereby making sure that if a system
or application service fails, the affected services fail over to another system
in the same cluster or, if an entire cluster or site fails, the SAP application
itself fails over to the remote cluster. Then, once the application is online,
clients are automatically redirected to the new location. This not only ensures
the availability of SAP in the event of a disaster, but it also enhances manageability
by providing a single point of management for the entire SAP application rather
than offering management on a per-SAP-component basis only.
Software-based volume replication solutions further enhance data center availability
and protect business continuity by enabling site migration at the click of a
button. Replication tools that work over any IP network ensure maximum efficiency
and flexibility, while solutions that support a variety of replication configurationsincluding
one-to-one, one-to-many, and many-to-onehelp streamline business continuity
efforts and ease management.
For global failover scenarios, organisations often use volume replication tools
that support asynchronous replication. With asynchronous replication, replication
operations queue for network availability, which produces the highest performance
but introduces the potential for data loss.
A number of replication tools also offer synchronous replication, which guards
against data loss but may impact performance. However, a small number of replication
solutions today offer enhanced asynchronous replication by enforcing write order
on the replicated site, which ensures data integrity and consistency and guarantees
that data will be recoverable at the secondary site.
Technical solutions to business continuity needs help automate critical procedures,
reduce administrative costs, increase efficiency, and minimise error. These
technologies can be complemented by a business continuity plan that incorporates
best practices for assessing risk factors, implementing a datacenter availability
strategy, testing without disrupting production servers and validating the technologies
and activities established to protect essential business services.
A business continuity plan provides a structured approach for the development
of the architecture, processes, and practices for both identifying and reaching
recovery time and recovery point objectives.
To help build the most comprehensive and effective strategy and plan, organisations
can leverage the expertise of certified business continuity professionals who
can provide benchmarks, identify bottlenecks, and recommend solutions that address
the requirements of auditors, shareholders, C-level executives, and other corporate
Protecting the availability, manageability, and recoverability of SAP applications
is critical to ensuring business continuity. SAP applications form the foundation
of an organisations most vital processes. As a result, downtime is simply
not an option.
By leveraging advanced technologies that provide global clustering and replication
of the SAP environment across geographically distributed, heterogeneous sites,
and by complementing these technologies with sound best practices, organisations
can not only keep their businesses up and running, but growing as well.
By Vishal Dhupar, Managing Director, Symantec India