Definitons

  • DKC - Disk controller, can also hold 128 drives in a USP-V
  • DKU - Disk expansion unit, holds 256 drives in a USP-V
  • CHA - Channel adapters, cache to host, contain host ports
  • DKA - Disk adapters, cache to disk, connec to back end drives
  • CSW - Cache switch, controls movement from cache to hosts and drives

This can be represented as follows:

USP-V CSW

CSW + 1D/2P controls CHA0+1 and DKA0+1. If additional CHAs/DKAs are added, an additional CSW is required at 1J/2V

The USP-V is split into Cluster 1 (front) and Cluster 2 (back). These contain 16 or 8 port CHAs. The port numbers are as follows:

CL1 CL1 CL2
CHA0 CHA1
1A 3A 1E 3E 2A 4A
5A 7A 5E 7E 6A 8A
1B 3B etc etc
5B 7B
1C 3C
5C 7C
1D 3D
5D 7D
(odd numbers)(even numbers)

A 16 port CHA has 8 processors, CHP00 controls 1A & 5A, CHP01 3A & 7A, etc

Queue depths

USP-V USP
1024 queued commands per port 512
32 queued commands per LUN 32

So if a SCSI queue depth on a server (sd_max_throttle on Solaris) is set to 32, the maximum recommended LUNs per port will be 32 (32 x 32 = 1024)

Recent Changes