Deploying Silver Peak With Emc Vplex

Deploying Silver Peak VXOA with EMC VPLEX Geo

November 2011

www.silver-peak.com

Overview ................................................................................................................................................................................................................... 3

Figure 1: Silver Peak with VPLEX ............................................................................................................................................................... 3

Solution Components ................................................................................................................................................................................................ 4

EMC VPLEX ..................................................................................................................................................................................................... 4

Silver Peak Appliances .................................................................................................................................................................................... 4

Deployment Architectures ........................................................................................................................................................................................ 6

Figure 2: One side of a Redundant Deployment with Single WAN ............................................................................................................ 6

Figure 3: One Side of a Redundant Deployment with Redundant WAN .................................................................................................... 7

MTU Configuration .................................................................................................................................................................................................... 7

VPLEX Configuration .................................................................................................................................................................................................. 8

Setting the VPLEX keepalive-timeout value .................................................................................................................................................... 8

Setting the VPLEX MTU size ............................................................................................................................................................................ 8

Silver Peak Configuration .......................................................................................................................................................................................... 9

Figure 4: Configuring Silver Peak tunnel options ....................................................................................................................................... 9

Router PBR Configuration .................................................................................................................................................................................. 10

Monitoring Performance ................................................................................................................................................................................... 11

Figure 5: VPLEX WAN Port Performance Monitoring .............................................................................................................................. 12

Figure 6: VPLEX System-wide WAN Link Usage ....................................................................................................................................... 13

Figure 7: VXOA WAN traffic report .......................................................................................................................................................... 13

Figure 8: VXOA Bandwidth Reduction and Throughput Report ............................................................................................................... 14

Conclusion ............................................................................................................................................................................................................... 14

Links ........................................................................................................................................................................................................................ 15

Table of Contents

© Copyright 2011 Silver Peak Systems, Inc. All rights reserved. All other brands, products, or service names are or may be trademarks or service marks of, and are used to identify. Products or services of their respective owners.

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Overview Silver Peak develops data center class network appliances that maximize WAN performance while

minimizing WAN costs. Offered in both physical and virtual (software) options, Silver Peak’s WAN

optimization solutions scale from Mbps to Gbps of WAN capacity. By optimizing primarily at the network

layer, Silver Peak can optimize all IP traffic, regardless of transport protocol. This provides a great deal of

flexibility for geographically distributed VPLEX environments, where different protocols may be

employed by the hosts attached on the front end and by the VPLEX clusters that move data over the

WAN.

Figure 1: Silver Peak with VPLEX

As shown in Figure 1, Silver Peak appliances are easily deployed between VPLEX Geo clusters on both

ends of the WAN. Silver Peak, when deployed with VPLEX Geo, mitigates many challenges associated

AccessAnywhere


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with deploying a geographically distributed architecture, including limited bandwidth, latency, and WAN

quality.

This document provides information on deployment architecture and best practices for EMC VPLEX Geo

and Silver Peak appliances.

Solution Components

EMC VPLEX

The EMC VPLEX family removes physical barriers and enables users to access a single copy of data at

different geographical locations. It also enables geographically stretched virtual and physical host

clusters with transparent load sharing between multiple sites. This provides the flexibility of relocating

workloads between sites in anticipation of planned events. In case of an unplanned event that could

cause disruption at one of the data centers, the failed services can be restarted at the surviving site with

minimal effort, minimizing time to recovery.

VPLEX is an appliance that resides between the servers and heterogeneous storage assets. It uses a

unique clustering architecture that enables servers at multiple data centers to have read/write access to

shared block storage devices. With its unique scale-up and scale-out architecture, VPLEX’s advanced

data caching and distributed cache coherency provides workload resiliency, automatic sharing,

balancing, and failover of storage domains. It also enables both local and remote data access with

predictable service levels.

VPLEX Geo dissolves the distance between data centers by introducing data mobility between sites

located at asynchronous distances (up to 50 ms of round trip latency). This is the industry’s first

platform for distributed federation over asynchronous distance.

Silver Peak Appliances

Silver Peak WAN optimization appliances maximize WAN performance while minimizing costs. Silver

Peak appliances can be deployed as physical or virtual machines and utilize the Virtual Acceleration

Open Architecture, VXOA. VXOA enables real-time optimization at the network (IP) layer with Network

Memory for deduplication and compression, Network Integrity for correct packet delivery issues and

Network Acceleration to mitigate the effects of latency.

Silver Peak appliances are deployed with EMC VPLEX Geo to mitigate the effects of latency, reduce the

bandwidth required for replication and maintain the transport integrity of the WAN.

• Network Memory: Reduces the amount of bandwidth required for VPLEX and associated

application traffic. The amount of reduction is dependent on the data set in use, with typical rates

from 50 to 90%. Reduction can vary within the data set and it is not uncommon to see reduction


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increase as more data in transmitted. Each Silver Peak appliance inspects WAN traffic at the byte

level and stores copies of content in local storage. Advanced finger-printing techniques recognize

repetitive patterns and, if the remote appliance already contains the information, the data will not

resent over the WAN. This dramatically increases the amount of bandwidth available, allowing

customers to use a significantly smaller WAN connection for their VPLEX deployments.

• Network Integrity: Even a small amount of packet loss on a WAN can greatly reduce throughput of

storage applications. Silver Peak Network Integrity is a collection of “line conditioning”

technologies which enable VPLEX to use a lower cost, shared WAN infrastructure instead of

significantly more expensive dedicated links. 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 they were sent.

Together, these features address packet delivery errors without requiring re-transmissions,

resulting in maximum performance across low cost, shared environments like Multiprotocol Label

Switching (MPLS) and IP Virtual Private Networks (VPNs). Advanced quality-of-service (QoS)

techniques can prioritize VPLEX traffic and guarantee that bandwidth requirements are met.

• Network Acceleration: As distance grows, latency becomes more of an issue and, when combined

with packet loss, the results can be extremely detrimental to application performance over the

WAN. Silver Peak Network Acceleration complements existing EMC VPLEX Geo technologies by

accelerating mobility across the WAN for host-based applications. Using techniques like TCP

window size management, TCP selective acknowledgements, and other methods to mitigate the

impact of latency, this enables enterprises to safely stretch the distance between data centers.

When combined, VPLEX and Silver Peak enable enterprises to safely stretch the distance between

data centers while maintaining Recovery Point Objectives (RPO) and Recovery Time Objectives

(RTO).

• Network Visibility and Monitoring: Provides simplified management, monitoring, and alerting in

VPLEX environments. Silver Peak Global Management System (GMS) and Silver Peak dashboards

can collect and display network conditions and associated VPLEX traffic across the WAN, enabling

customers to quickly diagnose and resolve any VPLEX or application-layer throughput issues as a

result of WAN conditions.

• Security: Silver Peak can enhance data security by using IPSec to secure data replicated across the

WAN. To ensure security of data-at-rest on the Silver Peak appliances themselves, AES encryption

is used to encrypt all data stored on Silver peak devices.


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Deployment Architectures Silver Peak VXOA can be deployed in the network in two different methods, Bridge mode or Router

mode. In Bridge mode, Silver Peak appliances are deployed as a “bump in the wire” between the LAN

infrastructure and the WAN router. In Router mode, Silver Peak appliances are deployed in “one-

armed”, or “lollipop”, fashion with a single connection to the WAN router. When Router mode is used, a

redirection method like Policy Based Routing or Web Cache Communications Protocol is used to direct

traffic to the appliance. For redundancy, Policy Based Routing deployments use the Virtual Router

Redundancy Protocol to fail over between appliances.

Review the Silver Peak WAN Optimization Appliances Network Deployment Guide for more information

on deployment methods.

VPLEX Geo relies on WAN bandwidth for replication and cache coherency. Because WAN bandwidth is

so important to VPLEX Geo, Silver Peak appliances must be deployed in a redundant configuration.

When used with VPLEX Geo, Silver Peak appliances should be deployed out of path with Policy Based

Routing (PBR) and the Virtual Router Redundancy Protocol (VRRP). WCCP and Bridge deployments with

VPLEX Geo are not supported at this time. For detailed instructions on configuring Silver Peak appliances

for PBR and VRRP please see the document “Silver Peak WAN Optimization Appliances Network

Deployment Guide”.

The following diagrams show one side of a link with a single and redundant WAN router and circuit.

Figure 2: One Side of a Redundant Deployment with Single WAN

VPLEX

Router

Silver Peak

Silver Peak

Storage

WAN

VRRP

1 GbE/10 GbE

Fibre Channel

WAN


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Figure 3: One Side of a Redundant Deployment with Redundant WAN

MTU Configuration During testing Silver Peak and EMC discovered that increasing the MTU size on the VPLEX can increase

replication performance by as much as 25%. Increasing the MTU size on the VPLEX also requires

increasing the MTU size on the Silver Peak tunnel. If the MTU is not increased on the Silver Peak tunnel,

packets from the VPLEX will be broken apart to match the MTU of the WAN, typically 1500. When the

Silver Peak tunnel is configured for the larger MTU size, it will manage the transmission of data across

the WAN, maintaining the performance increase from the VPLEX, and will maintain an MTU size that is

compatible with the WAN. If the Silver Peak appliance experiences a failure and a redundant device is

not deployed, the VPLEX will see reduced performance. The reduced VPLEX performance will be greater

than if the MTU size had not been changed. Because of the potential for performance degradation, the

Silver Peak appliances must be deployed in a redundant configuration. If redundant Silver Peak

appliances are not deployed, the VPLEX MTU size should be left at the default setting of 1500.

VPLEX

RouterRouter

Silver Peak

Silver Peak

Storage

WAN

VRRP

1 GbE/10 GbE

Fibre Channel

WAN


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VPLEX Configuration VPLEX Geo should be configured according to the EMC VPLEX with GeoSynchrony Configuration Guide

with two exceptions: the port-group MTU size should be set to 2300 (please see the section MTU

Configuration before making this change) and the UDT keepalive-timeout value needs to be increased.

Setting the VPLEX keepalive-timeout value

In order to set the UDT keepalive-timeout value, use the following commands from the VPLEX CLI:

VPlexcli:/> set /clusters/<cluster-ID>/cluster-connectivity/options-sets/optionset-com-[01]::keepalive-timeout

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Setting the VPLEX MTU size

To set the MTU size to 2300 use the following command at the VPLEX CLI:

VPlexcli:> set /clusters/<cluster-ID>/cluster-connectivity/subnets/default-subnet::mtu 2300

This command needs to be repeated on each cluster at the local and remote site.

For complete VPLEX Geo configuration, please see the following VPLEX documentation available at

powerlink.emc.com:

EMC VPLEX with GeoSynchrony CLI Guide

EMC VPLEX with GeoSynchrony Configuration Guide


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Silver Peak Configuration The following settings need to be configured on the Silver Peak appliances:

WAN Bandwidth = environment dependent Network Memory = mode 1

FEC = enabled (1:5 or 1:10) Window Scale Factor = 8

MTU = 2400

Tunnel Retry Count = 3

Congestion Control = optimized

When the MTU is changed to 2300 on the VPLEX port groups, a corresponding change must be made to

the Silver Peak appliances (please see the section MTU Configuration before making this change). In the

Silver Peak VXOA GUI change the MTU to 2400 for any tunnel that carries VPLEX traffic. The Silver Peak

VXOA MTU setting is higher than the VPLEX MTU setting to reserve some capacity for overhead.

FEC is also set per tunnel and should be enabled at either 1:5 or 1:10 based on the amount of loss on the

WAN. For WAN connections with higher loss, a value of 1:5 should be used. More information is

available in the Silver Peak Appliance Manager Operator’s Guide.

Figure 4: Configuring Silver Peak tunnel options

The following CLI commands are used to set congestion control, Network Memory mode, tunnel retry

count and window scale factor:

interface tunnel <tunnel name> acceleration tcp congest-control optimized

interface tunnel <tunnel name> acceleration tcp window-scale <tcp-ws-factor>

system network-memory mode 1


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interface tunnel <tunnel name> threshold retry-count 3

Router PBR Configuration The PBR configuration on the router must use either IP SLA or the Silver Peak appliance must be directly

connected to a physical router interface. This setting makes sure to keep the Silver Peak appliance in the

same state as the WAN. For example, if the WAN connection fails, the PBR policy will also disable the

connection to the Silver Peak appliance, allowing the VPLEX to recognize the connectivity failure faster.

When IP SLA is used with PBR, the IP SLA tracker must have the delay up value set to 60 and the delay

down value set to 3.

In the following example we will create an IP SLA with ID 2 on a router, enable access to VLAN 170 on

the router LAN port, and apply PBR on the router. The Silver Peak appliance WAN port is 10.1.14.200

and the VPlex Ethernet ports are on subnets 10.1.10.0, 10.1.12.0, 10.1.20.0 and 10.1.22.0.

The following commands configure an IP SLA with ID2 and the following attributes:

1. Ping 10.1.14.200 once every second (icmp-echo 10.1.14.200, frequency 1).

2. Max wait time for the ping response before it is declared a miss is 1000ms (timeout 1000).

3. Threshold value of ping response time is 100ms (threshold 100).

ip sla 2

icmp-echo 10.1.14.200

timeout 1000

threshold 100

frequency 1

This command activates IP SLA with ID 2 immediately and specifies that it run indefinitely:

ip sla schedule 2 life forever start-time now

The following commands create a track object with ID 123 to track IP SLA with ID 2. The client is notified

of a state change from down to up after a 30 second delay and up to down after a 5 second delay.

track 123 ip sla 2 reachability

delay down 5 up 30

The following commands enable VLAN 170 access on the 1- GbE router LAN port 3/5:

interface TenGigabitEthernet3/5

description VPlex

switchport

switchport access vlan 170

switchport mode access

mtu 9126


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Next PBR is applied (ip policy route-map VPlex) on VLAN 170, the router for VLAN 170 is using

the IP address 10.1.11.3:

interface vlan 170

description VPlex

mtu 9216

ip address 10.1.11.3 255.255.255.0

no ip redirects

ip policy route-map VPlex

With these commands the PBR policy will redirect all traffic meeting the criteria specified in ACL 170

(Extend IP access list 170) to IP address 10.1.14.200, the Silver Peak appliance, while track 123

is used to verify the reachability of the IP address:

route-map VPlex permit 10

match ip address 170

set ip next-hop verify-availability 10.1.14.200 1 track 123

Extended IP access list 170

10 permit ip 10.1.10.0 0.0.0.255 10.1.20.0 0.0.0.255 (2050083501 matches)

20 permit ip 10.1.12.0 0.0.0.255 10.1.22.0 0.0.0.255 (2004833373 matches)

Monitoring Performance

VPLEX Reporting

The VPLEX management GUI provides reporting on replication traffic and includes graphs for WAN Port

Performance and System-wide WAN Usage as seen by the VPLEX. These charts provide data on the

bandwidth being used by the VPLEX system; the actual WAN bandwidth usage will be lower due to Silver

Peak Network Memory.


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Figure 5: VPLEX WAN Port Performance Monitoring


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Figure 6: VPLEX System-wide WAN Link Usage

Silver Peak Reporting

The Silver Peak appliances provide detailed reporting on the current and historic state of the WAN with

performance, integrity, application and protocol specifics. Silver Peak reports can be used to verify

throughput and utilization of the WAN, traffic flow by application and data reduction.

Figure 7: VXOA WAN traffic report


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Figure 8: VXOA Bandwidth Reduction and Throughput Report

Conclusion EMC VPLEX Geo allows enterprises to manage data storage and usage in new ways. Data sharing over

distance requires efficient and stable WAN connections. Silver Peak appliances help to optimize VPLEX

Geo deployments and enable rapid movement of data across longer distances. Together, EMC VPLEX

and Silver Peak appliances provide a complete solution for managing data and availability across

distance.


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Links Silver Peak documentation: http://www.silver-peak.com/Support/user_docs.asp

Silver Peak information: http://www.silver-peak.com/

EMC VPLEX information: http://www.emc.com/storage/vplex/vplex.htm

EMC VPLEX documentation: https://powerlink.emc.com

Documents

Deploying Silver Peak With Emc Vplex