HP P6000 Continuous Access Implementation Guide (T3680-96431, August 2012)

NOTE: With HP B-series switches the SID/DID protocol is known as Port-based routing; with HP
C-series switches the SID/DID protocol is known as Flow based load balancing. Both B-series and
C-series switches use exchange-based routing terminology for SID/DID and originator exchange
ID (OXID) routing.
The original replication protocol used with HP P6000 Continuous Access is HP FC Data Replication
Protocol (HP-FC). This protocol uses multiple exchanges for each data replication transfer. One or
more exchanges are used to transfer data, and an additional exchange is used for command
information. HP-FC requires that all frames in the transfer be delivered in order using the same
path even if they are for different exchanges. Therefore, if HP-FC is enabled, the fabric must use
SID/DID routing.
The new HP SCSI FC Compliant Data Replication Protocol (HP SCSI-FCP) is a full SCSI protocol
implementation and can take advantage of the exchange-based routing available in fabric switches.
Replication data transfer SCSI exchanges can use alternate paths.
HP SCSI-FCP and HP-FC protocols are supported on controller software versions 0953xxxx or later;
earlier versions of the controller software support HP-FC only. The successful creation of DR groups
requires that both the source and destination arrays be configured for compatible replication
protocols.
NOTE: H-series FC switches are only supported with XCS 09534000 or later and the HP SCSI-FCP
protocol. For the latest information about supported firmware, see the P6000/EVA Array Streams
and the H-series FC Switch Connectivity Stream on the HP Single Point of Connectivity Knowledge
(SPOCK) website at http://www.hp.com/storage/spock.
You must sign up for an HP Passport to enable access.
Selecting the data replication protocol
When selecting the data replication protocol for the array, three options are available. The three
available options are shown in “Data replication protocol selection” (page 40). The option currently
being used is indicated by the option selected.
• HP FC Data Replication Protocol (HP-FC)—Choosing this option requires that all transfers be
completed in order, which is accomplished by the proper configuration of the SAN fabric
switches for SID/DID. For more information on the required switch settings, see “Verifying
Fibre Channel switch configuration” (page 51).
NOTE: HP-FC protocol should not be used with a SAN configured for exchange-based
routing.
An array configured for HP-FC will successfully create a DR group only with another array
using HP-FC. HP-FC is the default protocol for controller software versions prior to XCS
0953xxxx and can be selected as a protocol in later versions. Use of HP-FC with improper
fabric configuration will result in significant performance degradation.
• HP SCSI FC Compliant Data Replication Protocol (HP SCSI-FCP)—Choosing this option supports
the transfer of data replication traffic in a fabric configured for exchange-based (SID/DID
OXID) routing. This protocol takes advantage of the exchange-based fabric setting, but is not
dependent on the fabric setting. Exchange-based routing is not required when using this
protocol. For more information on the required switch settings, see “Verifying Fibre Channel
switch configuration” (page 51).
• Either—Choose this option when the SAN contains arrays running both HP-FC and HP SCSI-FCP
protocols. This option enables arrays capable of HP-FC only to successfully create DR groups
with arrays running controller software version 0953xxxx or later. This facilitates the migration
of data from older arrays to newer arrays. The same fabric considerations for HP FC Data
Replication Protocol also apply to the Either option.
Planning the data replication protocol 39