Справочник Пользователя для ASUS PEM-FDR

Rev 2.0-3.0.0

Mellanox Technologies

41

As described in 

, the SCSI RDMA Protocol (SRP) is designed to take full advantage 

of the protocol off-load and RDMA features provided by the InfiniBand architecture. SRP allows 
a large body of SCSI software to be readily used on InfiniBand architecture. The SRP Initiator 
controls the connection to an SRP Target in order to provide access to remote storage devices 
across an InfiniBand fabric. The SRP Target resides in an IO unit and provides storage services.

 describes the SRP Initiator included in Mellanox OFED for Linux. This package, 

however, does not include an SRP Target.

This SRP Initiator is based on open source from OpenFabrics (

www.openfabrics.org

) that imple-

ments the SCSI RDMA Protocol-2 (SRP-2). SRP-2 is described in Document # T10/1524-D 
available from 

http://www.t10.org

.

The SRP Initiator supports
• Basic SCSI Primary Commands -3 (SPC-3)

(www.t10.org/ftp/t10/drafts/spc3/spc3r21b.pdf)

• Basic SCSI Block Commands -2 (SBC-2)

(www.t10.org/ftp/t10/drafts/sbc2/sbc2r16.pdf)

• Basic functionality, task management and limited error handling

To load the SRP module, either execute the “

modprobe ib_srp

” command after the OFED driver 

is up, or change the value of SRP_LOAD in 

/etc/infiniband/openib.conf

 to “yes”.

For the changes to take effect, run: /etc/init.d/openibd restart

When loading the ib_srp module, it is possible to set the module parameter 
srp_sg_tablesize. This is the maximum number of gather/scatter entries per I/O 
(default: 12).