Dell EqualLogic replication and Silver Peak WAN optimization

Solution Brief
Dell EqualLogic replication and Silver Peak WAN optimization
enhance offsite data protection and multi-site backup
The Silver Peak and Dell EqualLogic
solution can enable enterprises of all
sizes to achieve the following:
• Improve Recovery Point Objectives (RPO)
and Recovery Time Objectives (RTO)
• Reduce WAN bandwidth costs
• Maximize replication throughput across
the WAN
• Mitigate the constraints of distances
among data centers, remote operations
and disaster recovery sites
Dell™ EqualLogic™ PS Series virtualized iSCSI Storage Area Networks (SANs) leverage
numerous benefits inherent in the standard iSCSI protocol, including its high
ease-of-use, low networking infrastructure costs and low total cost of ownership
(TCO). When layered on top of TCP/IP, iSCSI storage can utilize IP-based Wide
Area Networks (WANs) as the foundation for consolidating backup processes
and enabling disaster recovery. The PS Series Auto-Replication feature (which
comes standard – no additional activation fees or licenses – with all PS Series
arrays) can leverage enterprise WANs to cost-effectively replicate data between
geographically distributed sites.
Dell EqualLogic SANs, in combination with Silver Peak’s data-center class WAN
optimization, offer a proven solution for offsite data protection and centralized
backup. With the combined Dell and Silver Peak solution, enterprises can
protect more data across longer distances, while leveraging cost-effective
shared WAN technologies (such as MPLS, Internet VPNs) to help lower ongoing
IT costs.
Simplified operations for disaster recovery and multi-site backup
The WAN-optimized replication solution provided by Dell EqualLogic SANs and
Silver Peak appliances effectively support two strategic imperatives: disaster
recovery and multi-site backup. Disaster recovery strategies address the need
to safeguard data against natural disasters, human error and malice. Enterprises
can manage against these risks by replicating primary data at secondary sites.
EqualLogic Auto-Replication periodically replicates data from primary sites to
designated disaster recovery sites, while Silver Peak appliances help optimize
data center replication across the WAN. Should cataclysmic outages occur, IT
managers can leverage these secondary sites as interim data centers, utilizing
this remote data until primary sites recover, to help maintain high business
continuity with minimal loss.
Silver Peak appliances are seamlessly deployed on both ends of a WAN link, between the WAN router
and storage array. Out-of-path deployment options also exist.
Multi-site backup strategies, on the other hand, can help
centralize the management, processing and protection of
enterprise data that may – as a result of distributed operations
– be decentralized across regional, national, or international
boundaries. This distribution of business-critical data across
physical sites can compound the challenges of data backup and
security. Silver Peak appliances and Dell EqualLogic PS Series
arrays can help maximize WAN performance and efficiency in
this process, and allow enterprises to consolidate data backup
processes into primary data centers.
Boosting replication throughput using real-time
network optimization
Dell EqualLogic PS Series Auto-Replication enables the
creation and updating of replicas of volumes (i.e. LUNs) on a
recurring, scheduled basis. Replication refresh rates depend
upon a volume’s ongoing page-level changes and the effective
bandwidth that has been dedicated between replication partners.
Although ongoing replications are very efficient, WAN bandwidth,
latency and quality challenges still can prevent replication
from performing at its true potential. When these challenges
exist, WAN optimization is recommended to boost replication
performance and minimize the risk of data loss. Optimizing WAN
throughput specifically for replication traffic, therefore, can be
critical for achieving target performance levels for both multi-site
backup and disaster recovery operations.
Silver Peak’s VX and NX appliances complement the Dell
EqualLogic SAN solution by overcoming the common WAN
challenges that adversely impact replication performance between
source and target locations. More specifically, the Silver Peak
solution mitigates bandwidth, distance and WAN quality issues by
using the following real-time network optimization techniques:
• Network integrity: Silver Peak’s VX and NX appliances
provides a variety of real-time optimization techniques to
“clean up” WAN links for better effective throughput. Forward
Error Correction (FEC) rebuilds lost packets on the far end
of a WAN connection, and Packet Order Correction (POC)
ensures that all packets are delivered in the order in which
they were sent. Silver Peak appliances also use advanced
Quality of Service (QoS) techniques to prioritize traffic and
ensure that necessary bandwidth requirements are met.
• Network memory: Silver Peak’s appliances use diskbased deduplication to eliminate the transfer of duplicate
information sent across the WAN during the replication
process. By working at the byte level, Silver Peak typically
delivers an additional 60% to 90% more “virtual bandwidth”
for data replication and remote SAN access. The Silver
Peak solution has the unique advantage of performing
compression and deduplication on all IP traffic (e.g.,
replication and other application data) traversing the WAN.
• Network acceleration: TCP acceleration helps to overcome
latency between source and target locations. By adjusting the
TCP window size and performing selective acknowledgements,
Silver Peak’s Network Acceleration techniques mitigate the
impact of latency on long-distance replication.
Silver Peak’s Global Management System (GMS) also provides
real-time and historical analysis of WAN performance, including
detailed reports on bandwidth, latency, and packet loss. This can
be used for capacity planning, ongoing network and application
monitoring, and rapid troubleshooting. With Silver Peak’s GMS,
IT administrators can monitor the performance of all IP traffic
traversing the WAN and export key information to third-party
systems using Netflow.
Maximize replication performance across the WAN
The combined Dell EqualLogic and Silver Peak solution
maximizes the utilization of WAN bandwidth when doing offsite
replication. In addition, Silver Peak ensures Dell EqualLogic
replication performs at its full potential on shared networks,
which delivers substantial WAN bandwidth cost savings to
enterprises. Lastly, the combined Silver Peak and Dell EqualLogic
solution enables replication to take place across long distances
with little or no decrease in throughput.
By deploying Dell EqualLogic with Silver Peak’s VX and NX
appliances, enterprises have more flexibility in how they setup
their disaster recovery processes, and can substantially lower
their disaster recovery costs. Perhaps most importantly, the
combined Silver Peak and Dell Equallogic solution minimizes
Recovery Point Objectives (RPO), which ultimately reduces
exposure to data loss.
Simplify your Storage at www.dell.com/PSseries
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