lsscsi version 0.19 beta

The last announcement I made to this list about lsscsi was back in March and that was a beta for lsscsi version 0.18 . The change proposed by James Bottomley that prompted the beta has not materialized. So I decided to release version 0.18 without fanfare a week ago and start adding transport information to lsscsi, dubbing it version 0.19 beta. See http://www.torque.net/scsi/lsscsi.html for downloads.

The mushrooming of information (and different representations) in /sys has made it possible for lsscsi to provide a lot more information than it has previously. Ironically what storage device identification really needs is not available, namely the logical unit _name_ which, for SCSI devices, is obtained from the device identification VPD page (0x83). As a consolation there is lots of transport information.

So this beta adds transport information, both target and initiator (host) for these transports:
- FC
- SAS

I hope to add iSCSI if I can find a way through its maze. Perhaps USB and 1394 are candidates as well, even SPI. In the case of SAS, both the SAS transport layer and the SAS class (i.e. Luben Tuikov's design) representations are supported.

The new options are '--transport' (or '-t') and '--list' (or '-L').

Here is an example where disk strings are insufficient:

# lsscsi
[4:0:0:0]    disk    ATA      ST3160812AS      D     /dev/sda
[4:0:1:0]    disk    SEAGATE  ST336754SS       0003  /dev/sdb
[4:0:2:0]    disk    SEAGATE  ST336754SS       0003  /dev/sdc
[4:0:3:0]    disk    ATA      ST380013AS       3.18  /dev/sdd
[4:0:4:0]    disk    SEAGATE  ST336754SS       0003  /dev/sde
[4:0:5:0]    disk    SEAGATE  ST336754SS       0003  /dev/sdf
[5:0:0:0]    disk    SEAGATE  ST336754SS       0003  /dev/sdg
[5:0:1:0]    disk    SEAGATE  ST336754SS       0003  /dev/sdh
[5:1:0:0]    disk    SEAGATE  ST336754SS       0003  /dev/sdi
[5:1:1:0]    disk    SEAGATE  ST336754SS       0003  /dev/sdj

How many disks are there? Looking at the transport information:

# lsscsi -t
[4:0:0:0]    disk    sas:0x0b1d2c035c7e5d4c          /dev/sda
[4:0:1:0]    disk    sas:0x5000c500005208ed          /dev/sdb
[4:0:2:0]    disk    sas:0x5000c50000520a29          /dev/sdc
[4:0:3:0]    disk    sas:0x500605b0000033e1          /dev/sdd
[4:0:4:0]    disk    sas:0x5000c500005208ee          /dev/sde
[4:0:5:0]    disk    sas:0x5000c50000520a2a          /dev/sdf
[5:0:0:0]    disk    sas:5000c500005208ed            /dev/sdg
[5:0:1:0]    disk    sas:5000c50000520a29            /dev/sdh
[5:1:0:0]    disk    sas:5000c500005208ee            /dev/sdi
[5:1:1:0]    disk    sas:5000c50000520a2a            /dev/sdj

So everything is SAS attached, including two SATA disks. Something strange is happening with 4:0:0:0 which is directly attached to the host4. From the target SAS addresses it can be seen that /dev/sdc and /dev/sdh are the same port (and because the lun is 0 in both cases, it must be the same lu). There are three other pairs there, reducing what looks like 10 disks to six. The adjacent SAS addresses are dual ports on the same disk, so the actual number of disks is 4. Why are some SAS addresses prefixed with 0x and other not? lsscsi simply prints out what is in /sys !

To fetch further information about the target that contains /dev/sdf using a filter to reduce clutter:

# lsscsi --transport --list 4:0:5:0
[4:0:5:0]    disk    sas:0x5000c50000520a2a          /dev/sdf
  transport=sas
  initiator_port_protocols=none
  initiator_response_timeout=0
  I_T_nexus_loss_timeout=1744
  phy_identifier=11
  ready_led_meaning=0
  sas_address=0x5000c50000520a2a
  target_port_protocols=ssp

A similar check on the target containing /dev/sdj

# lsscsi -t -L 5:1:1
[5:1:1:0]    disk    sas:5000c50000520a2a            /dev/sdj
  transport=sas
  sub_transport=sas_class
  device_name=0000000000000000
  dev_type=end device
  iproto=
  iresp_timeout=0x0000
  linkrate=3,0 Gbps
  max_linkrate=3,0 Gbps
  max_pathways=1
  min_linkrate=3,0 Gbps
  pathways=1
  ready_led_meaning=0
  rl_wlun=0
  sas_addr=5000c50000520a2a
  tproto=SSP
  transport_layer_retries=0

Finally here is a listing of hosts, then a listing of hosts with their initiator identifier (if known) and finally a closer look at host4 (with and without transport specific information):

# lsscsi --hosts
[0]    sata_nv
[1]    sata_nv
[2]    sata_nv
[3]    sata_nv
[4]    mptsas
[5]    aic94xx

# lsscsi --hosts --transport
[0]    sata_nv
[1]    sata_nv
[2]    sata_nv
[3]    sata_nv
[4]    mptsas        sas:0x500605b00006f260
[5]    aic94xx       sas:50000d10002dc000

# lsscsi -H -t --list 4
[4]    mptsas        sas:0x500605b00006f260
  transport=sas
  device_type=end device
  initiator_port_protocols=smp, stp, ssp
  invalid_dword_count=0
  loss_of_dword_sync_count=0
  maximum_linkrate=3.0 Gbit
  maximum_linkrate_hw=3.0 Gbit
  minimum_linkrate=1.5 Gbit
  minimum_linkrate_hw=1.5 Gbit
  negotiated_linkrate=Unknown
  phy_identifier=0
  phy_reset_problem_count=0
  running_disparity_error_count=0
  sas_address=0x500605b00006f260
  target_port_protocols=none

# lsscsi -H --list host4
[4]    mptsas
  can_queue=127
  cmd_per_lun=7
  host_busy=0
  sg_tablesize=128
  state=running
  unchecked_isa_dma=0
  unique_id=0

Doug Gilbert

In case you find the ieee1394/sbp2 transport insufficiently integrated, please point it out. I'd try to implement what's missing as spare time permits and as far as it doesn't add excessive baggage.

Stefan Richter
-=====-=-==- ==-- --===
http://arcgraph.de/sr/

You'll have to remind me: which change was this?

James

James,
Yes, I'm fuzzy on the details as well. Here is part of the lsscsi ChangeLog. Do the last two entries ring a bell?

Version 0.19 2006/12/06
- add transport identifiers (target+initiator, port+node)
- enhance host name search when proc_name is "<NULL>"
- implement filter option for '--hosts'
- accept 'host<n>' as first item in filter to mean host <n>
- output more host attributes when '-Hll' given
- add '--list' (or '-L') option output attribute=value entries, one per line

Version 0.18 2006/3/24
- cope with dropping of 'generic' symlink post lk 2.6.16
- anticipate the future removal of 'tape' symlink

Doug Gilbert

This one was supposed to be because you already have the class link:

generic@

and

scsi_generic:sg0@

So the necessary kernel changes (apart from the generic link removal) are already there.

I think this one is the same: st has its own class, which will have a symlink.

James

Further to the announcement 1 month ago (shown below), there is another lsscsi-0.19 beta at:
http://www.torque.net/sg [News section].
It provides target (and sometimes host) transport information for:
- IEEE1394 (sbp)
- FC
- ISCSI
- SAS (two representations)
- SPI

It has tested with lk 2.6.20-rc3 . Unfortunately fetching information out of sysfs could become a maze of kernel version dependencies as various maintainers change representations. This beta was tested with the intriguingly named SYSFS_DEPRECATED config option deselected. Sysfs is not deprecated yet (sigh) but deselecting SYSFS_DEPRECATED removes various symlinks which breaks earlier lsscsi betas.

Thanks to the maintainers of various SCSI transports for helping me find what information is available in sysfs and testing code for me. They are named in the CREDITS file.

Doug Gilbert

Douglas Gilbert wrote [2006/12/7]: