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I am looking for a scsi command that I can use to get device max link capability.

Can I use scsi MODE SENSE (page 19) to read the phy descriptors and get the link speed? But how is it different than max link speed and negotiated linkspeed?

rain
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1 Answers1

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According to SPL-4, you many use SMP DISCOVER function or SCSI MODE SENSE page 19h Protocol Specific Port, subpage 01h Phy Control And Discover.

For link speed, you should use NEGOTIATED LOGICAL LINK RATE. The max link speed are HARDWARE MAXIMUM PHYSICAL LINK RATE (physical limitation) and PROGRAMMED MAXIMUM PHYSICAL LINK RATE (configured by PHY CONTROL function)

This is the example of using SMP DISCOVER way:

[fge@el7 ~]$ sudo smp_discover /dev/bsg/expander-0\:0
  phy   0:T:attached:[500015535990a300:00  t(SATA)]  3 Gbps
  phy   1:T:attached:[500015535990a301:00  t(SATA)]  3 Gbps
  phy   2:T:attached:[500015535990a302:00  t(SATA)]  1.5 Gbps
  phy   3:T:attached:[500015535990a303:00  t(SATA)]  3 Gbps
  phy   4:T:attached:[500015535990a304:00  t(SATA)]  3 Gbps
  phy   5:T:attached:[500015535990a305:00  t(SATA)]  3 Gbps
  phy   6:T:attached:[500015535990a306:00  t(SATA)]  3 Gbps
  phy   7:T:attached:[500015535990a307:00  t(SATA)]  3 Gbps
  phy   8:T:attached:[500015535990a308:00  t(SATA)]  3 Gbps
  phy   9:T:attached:[500015535990a309:00  t(SATA)]  3 Gbps
  phy  10:T:attached:[500015535990a30a:00  t(SATA)]  3 Gbps
  phy  11:T:attached:[500015535990a30b:00  t(SATA)]  3 Gbps
  phy  12:T:attached:[500015535990a30c:00  t(SATA)]  3 Gbps
  phy  13:T:attached:[500015535990a30d:00  t(SATA)]  3 Gbps
  phy  14:T:attached:[50014ee5aaab876f:01  t(SSP)]  3 Gbps
  phy  15:T:attached:[500015535990a30f:00  t(SATA)]  3 Gbps
  phy  16:S:attached:[5d4ae520995f8200:03  i(SSP+STP+SMP)]  3 Gbps
  phy  20:T:attached:[500015535956633f:16 exp i(SMP) t(SMP)]  3 Gbps
  phy  21:T:attached:[500015535956633f:17 exp i(SMP) t(SMP)]  3 Gbps
  phy  22:T:attached:[500015535956633f:18 exp i(SMP) t(SMP)]  3 Gbps
  phy  23:T:attached:[500015535956633f:19 exp i(SMP) t(SMP)]  3 Gbps
  phy  24:D:attached:[500015535990a33e:24  V i(SSP) t(SSP)]  3 Gbps
Gris Ge
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