Policy Pages Reference : Optimization policy settings : SRDF
  
SRDF
You can enable and modify SRDF storage module optimization settings.
EMC’s Symmetrix Remote Data Facility/Asynchronous (SRDF/A) is a SAN replication product. It performs the data replication over GigE (instead of the Fibre Channel), using gateways that implement the SRDF protocol.
SRDF storage optimization provides support for environments using storage technology that originates traffic through Symmetrix GigE ports. For details about storage technologies that originate traffic through GigE RE ports, see the SteelHead Deployment Guide.
To increase the data reduction LAN-to-WAN ratio with either equal or greater data throughput in environments with SRDF traffic, RiOS separates the SRDF headers from the application data workload written to storage. The SRDF headers contain changing protocol state information, such as sequence numbers. These headers interrupt the network stream and reduce the ability of scalable data replication (SDR) to match large, contiguous data patterns. After isolating the header data, the appliance performs SDR network deduplication on the larger, uninterrupted storage data workload and LZ compression on the headers. RiOS then optimizes, reassembles, and delivers the data to the TCP consumer as originally presented to the SteelHead network.
Traffic originated through Symmetrix GigE ports (RE ports) requires configuration of the RiOS SRDF storage optimization module. Environments with SRDF traffic originated through Symmetrix FC ports (RF ports) require configuration of the RiOS FCIP storage optimization module.
For detailed information about SRDF, see the SteelHead User Guide. For details about data replication deployments, see the SteelHead Deployment Guide - Protocols.
Complete the configuration as described in this table.
Control
Description
Enable SRDF
Enables SRDF protocol. By default, RiOS directs all traffic on the standard port 1748 through the SRDF module for enhanced SRDF header isolation. For most environments, the configuration is complete.
SRDF Ports
Optionally, specify nonstandard individual SRDF port numbers separated by commas. Don’t specify a port range.
The SRDF ports field must always contain at least one port.
Apply
Applies your settings.
Add a Symm ID or Group Policy
Displays the tabs for adding a Symmetrix ID or group policy.
Add a Symm ID
Select this tab to display the controls for adding a Symmetrix ID.
Symm ID
Specify the Symmetrix ID. The Symmetrix ID is an alphanumeric string (for example, a standard Symmetrix serial number is 000194900363).
Each Symmetrix ID can have 0-254 group override policies.
Source IPs
Specify the connection source IP address of the Symmetrix DMX or VMAX GigE ports (RE ports) originating the replication.
Add a Group Policy
Select this tab to display the controls for adding a group policy.
RDF Group
Specify the RDF group number. Symmetrix arrays that are serving Open Systems hosts and are using EMC Solutions Enabler report RDF group numbers in decimal—ranging from 1 to 255 (this is the RiOS default).
Mainframe-attached Symmetrix arrays report RDF group numbers in hexadecimal, ranging from 0 - 255.
You can’t add an RDF group until a Symmetrix ID exists.
Symmetrix ID
Specify an IP address of the of the Symmetrix DMX or VMAX GigE ports (RE ports) originating the replication. The Symmetrix ID is an alphanumeric string (for example, a standard Symmetrix serial number is 000194900363).
Data Reduction Policy
By default, SDR uses the in-path rule data reduction policy. Select one of these data reduction policies from the drop-down list to override the in-path rule data reduction policy:
• Default—Performs LZ compression and SDR.
• LZ—Performs LZ compression; doesn’t perform SDR.
• None—Disables SDR and LZ compression.
Description
Describe the policy to facilitate administration: for example, Oracle 1 DB.
Add a New Rule
Displays the controls for adding a new rule.
Source IP
Specify the connection source IP address of the Symmetrix hosts originating the replication.
The source IP address can’t be the same as the destination IP address.
Destination IP
Specify the connection destination IP address of the Symmetrix hosts receiving the replication.
Enable DIF
Isolates and optimizes the Data Integrity Fields embedded within the SRDF data workload.
DIF Data Block Size (bytes)
Specify the size of a standard block of storage data, in bytes, after that a DIF header begins. The valid range is from 1 to 2048 bytes. The default value is 512, which is a standard block size for Open System environments. When you enable DIF, RiOS SRDF optimization looks for a DIF header after every 512 bytes of storage data unless you change the default setting.
Open System environments (such as Windows, UNIX, and Linux) inject the DIF header into the data stream after every 512 bytes of storage data. AS/400 host environments inject the DIF header into the data stream after every 520 bytes.
This field is required when you enable DIF.
Add
Adds the rule to the list.
Remove Selected
Select the check box next to the name and click Remove Selected.
Symmetrix IDs and group override policies
Complete the configuration as described in this table.
Control
Description
Add a Symm ID or Group Policy
Displays the tabs for adding a Symmetrix ID or group policy.
Add a Symmetrix ID
Select to display the controls for adding a Symmetrix ID.
Symm ID
Specify the Symmetrix ID. The Symmetrix ID is an alphanumeric string that can contain hyphens and underscores (for example, a standard Symmetrix serial number is 000194900363). Don’t use spaces or special characters.
Each Symmetrix ID can have 0 to 254 group override policies.
Source IPs
Specify the connection source IP address of the Symmetrix DMX or VMAX GigE ports (RE ports) originating the replication.
Add a Group Policy
Select to display the controls for adding a group policy.
RDF Group
Specify the RDF group number. Symmetrix arrays that are serving Open Systems hosts and are using EMC Solutions Enabler report RDF group numbers in decimal, ranging from 1 to 255 (this is the RiOS default).
Mainframe-attached Symmetrix arrays report RDF group numbers in hexadecimal, ranging from 0 to 254.
You can’t add an RDF group until a Symmetrix ID exists.
Symmetrix ID
Specify an IP address of the Symmetrix DMX or VMAX GigE ports (RE ports) originating the replication.
Data Reduction Policy
By default, SDR uses the in-path rule data reduction policy. Select one of these data reduction policies from the drop-down list to override the in-path rule data reduction policy:
• Default—Performs LZ compression and SDR.
• LZ—Performs LZ compression; doesn’t perform SDR.
• None—Disables SDR and LZ compression.
Description
Describe the policy to facilitate administration: for example, Oracle 1 DB.
Add
Adds the ID or policy to the list. The Management Console redisplays the list and applies your modifications to the running configuration, which is stored in memory.
Remove Selected
Select the check box next to the name and click Remove Selected.
Rules
The default rule optimizes all remaining traffic that hasn’t been selected by another rule. It always appears as the last in the list. You can’t remove the default rule; however, you can change the DIF setting of the default rule. The default rule uses 0.0.0.0 in the source and destination IP address fields, specifying all IP addresses. You can’t specify 0.0.0.0 as the source or destination IP address for any other rule.
Complete the configuration as described in this table.
Control
Description
Add a New Rule
Displays the controls for adding a manual rule. Use this control when the R1 Symmetrix array is running Enginuity microcode version 5874 or earlier.
Source IP
Specify the connection source IP address of the Symmetrix DMX or VMAX GigE ports (RE ports) originating the replication.
The source IP address can’t be the same as the destination IP address.
Destination IP
Specify the connection destination IP address of the Symmetrix DMX or VMAX GigE ports (RE ports) receiving the replication.
Enable DIF
Isolates and optimizes the Data Integrity Fields embedded within the SRDF data workload.
DIF Data Block Size
Specify the size of a standard block of storage data, in bytes, after which a DIF header begins. The valid range is from 1 to 2048 bytes. The default value is 512, which is a standard block size for Open System environments. When you enable DIF, RiOS SRDF optimization looks for a DIF header after every 512 bytes of storage data unless you change the default setting.
Open System environments (such as Windows, UNIX, and Linux) inject the DIF header into the data stream after every 512 bytes of storage data.
IBM iSeries (AS/400) host environments inject the DIF header into the data stream after every 520 bytes.
Don’t add a manual rule isolating DIF headers in mainframe environments, as SRDF environments that replicate mainframe traffic don’t currently include DIF headers.
This field is required when you enable DIF.
Add
Adds the manual rule to the list. The Management Console redisplays the Rules table and applies your modifications to the running configuration, which is stored in memory.
Remove Selected
Select the check box next to the name and click Remove Selected.
Move Selected
Moves the selected rules. Click the arrow next to the desired rule position; the rule moves to the new position.