LUN identification for the VMware ESX console

This section provides LUN identification information for the VMware ESX console.

Each of the attached storage unit LUNs has a special device file in the Console OS directory /dev. There is a maximum of 128 fibre-channel disks entries with the following format /dev/vsd [0 -127].

From the VMware ESX console, the storage unit can be traced through several layers:

Host adapter level: the Host Adapter driver can provide the list of LUNs that are detected for each fibre-channel port.
Vmhba level: VMware virtualizes the Host Adapter as a vmhba from which you can retrieve the information that is related to the multipathing.

Host adapter level

The Host Adapter driver (lpfccd for Emulex) (qla23xx for QLogic) can provide information on the port base. The content of the information varies according to the driver. The directory /proc/scsi/ <driver name> / <adapter number> will provide the information for a specific adapter/port. See Figure 1 for an example of QLogic output and Figure 2 for an example of Emulex output.

Figure 1. Example of QLogic Output:

[root@denethor root]# cat /proc/scsi/qla2310/2
QLogic PCI to Fibre Channel Host Adapter for ISP23xx:
        Firmware version:  3.01.18, Driver version 6.04.02
Entry address = 0x4d8000
HBA: QLA2312 , Serial# H88769
Request Queue = 0x210ec000, Response Queue = 0x21100000
Request Queue count= 128, Response Queue count= 512
Total number of active commands = 0
Total number of interrupts = 4008395
Total number of IOCBs (used/max) = (0/600)
Total number of queued commands = 0
    Device queue depth = 0x10
Number of free request entries = 128
Number of mailbox timeouts = 0
Number of ISP aborts = 90
Number of loop resyncs = 300
Number of retries for empty slots = 0
Number of reqs in pending_q= 0, retry_q= 0, done_q= 0, scsi_retry_q= 0
Host adapter:loop state= <DOWN>, flags= 0x860813
Dpc flags = 0x0
MBX flags = 0x0
SRB Free Count = 4096
Port down retry =  30
Login retry count =  30
Commands retried with dropped frame(s) =0


SCSI Device Information:
scsi-qla1-adapter-node=200000e08b0c2109;
scsi-qla1-adapter-port=210000e08b0c2109;
scsi-qla1-target-0=5005076300c6a3bb;
scsi-qla1-target-1=200500a0b80f0a15;
scsi-qla1-target-2=5005076300c6a6b8;
scsi-qla1-target-3=5005076300c2a6b8;
scsi-qla1-target-4=5005076300cfa6b8;

SCSI LUN Information:
(Id:Lun)
( 4: 0): Total reqs 7, Pending reqs 0, flags 0x0, 1:0:81,
( 4: 1): Total reqs 7132, Pending reqs 0, flags 0x0, 1:0:81,
( 4: 2): Total reqs 7414, Pending reqs 0, flags 0x0, 1:0:81,
( 4: 3): Total reqs 2948, Pending reqs 0, flags 0x0, 1:0:81,
...

Figure 2. Example of Emulex Output:

HBA: Emulex LightPulse LP9002 on PCI bus 06 device 28 irq 49
Emulex LightPulse LPFC Driver Version: 4.20q
SerialNum: MI23710129
Firmware Version: 3.90A7
Hdw: 2002606d
VendorId: 0xf90010df
Portname: 10:00:00:00:c9:2e:78:cc   Nodename: 20:00:00:00:c9:2e:78:cc

Link Up - Ready:
   PortID 0x71000a
   Fabric
   Current speed 2G

lpfc1t00 DID 71000e WWPN 50:05:07:63:00:cf:a6:b8 WWNN 50:05:07:63:00:c0:a6:b8

Vmhba level

The /proc/vmware/scsi directory will present 1 directory vmhba<N> where <N> is the host adapter. The directory will contain 1 entry per device (with a format <scsi id> : <LUN number>). See Figure 3 for an example of a Vmhba directory.

Figure 3. Example listing of a Vmhba directory

[root@denethor root]# ls /proc/vmware/scsi/vmhba0/
4:0   4:14  4:2   4:25  4:30  4:36  4:41  4:47  4:52  4:58  4:63  4:69  stats
4:1   4:15  4:20  4:26  4:31  4:37  4:42  4:48  4:53  4:59  4:64  4:7
4:10  4:16  4:21  4:27  4:32  4:38  4:43  4:49  4:54  4:6   4:65  4:70
4:11  4:17  4:22  4:28  4:33  4:39  4:44  4:5   4:55  4:60  4:66  4:71
4:12  4:18  4:23  4:29  4:34  4:4   4:45  4:50  4:56  4:61  4:67  4:8
4:13  4:19  4:24  4:3   4:35  4:40  4:46  4:51  4:57  4:62  4:68  4:9

Note: In a multipathing configuration, only 1 vmhba directory displays entries for the shared device.

Each of the entries provides information on the drives that it points to, as shown in Figure 4:

Figure 4. Example of Vmhba entries

[root@denethor root]# cat /proc/vmware/scsi/vmhba0//4\:71
Vendor: IBM       Model: 2105800           Rev: 1.89
Type:   Direct-Access                             ANSI SCSI revision: 03
Size:   24795 Mbytes
Queue Depth: 16


Partition Info:
Block size: 512
Num Blocks: 50781312

     num:    Start     Size     Type
       1:       63 50765337       fb


Partition     VM       cmds      reads     KBread     writes  KBwritten   cmdsAbrt
     busRst   paeCmds  paeCopies  splitCmds  splitCopies   issueAvg   totalAvg
        0      -        168         87         46          0          0 0          0
          0          0          0            0      20788     936149
        1      -       8837       8581      33869        128         64 0          0
          0          0          0             0      14038     762180

     VM  Shares      cmds      reads     KBread     writes  KBwritten   cmdsAbrt     busRst
    paeCmds  paeCopies  splitCmds  splitCopies   issueAvg   totalAvg    active     queued          
virtTime
    127    1000      9005       8668      33915        128         64          0          0
          0          0          0             0      14164     765426          0          0        
8728000000
  Total    1000      9005       8668      33915        128         64          0          0 
         0          0         0             0      14164     765426          0          0        
8728000000

Paths:fixed
  vmhba0:4:71 on*#
  vmhba1:4:71 on

Active: 0  Queued: 0

Note: The last section displays information on multipathing; refer to VMware documentation for more information on the multipathing configuration. The storage unit can interact with both FIXED and MRU policies.