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man pages section 8: System Administration Commands

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Updated: Wednesday, July 27, 2022

sg_ses_microcode (8)


sg_ses_microcode - send microcode to a SCSI enclosure


sg_ses_microcode  [--bpw=CS]  [--dry-run]  [--ealsd] [--help] [--id=ID]
[--in=FILE]   [--length=LEN]   [--mode=MO]    [--non]    [--offset=OFF]
[--skip=SKIP]  [--subenc=MS]  [--tlength=TLEN]  [--verbose] [--version]


SG_SES_MICROCODE(8)                SG3_UTILS               SG_SES_MICROCODE(8)

       sg_ses_microcode - send microcode to a SCSI enclosure

       sg_ses_microcode  [--bpw=CS]  [--dry-run]  [--ealsd] [--help] [--id=ID]
       [--in=FILE]   [--length=LEN]   [--mode=MO]    [--non]    [--offset=OFF]
       [--skip=SKIP]  [--subenc=MS]  [--tlength=TLEN]  [--verbose] [--version]

       This utility attempts to download microcode to an enclosure (or one  of
       its  sub-enclosures)  associated with the DEVICE. The process for doing
       this is defined in the SCSI  Enclosure  Services  (SES)  standards  and
       drafts maintained by the T10 committee.

       The  process  is  to  send one or more sequences containing a SCSI SEND
       DIAGNOSTIC command followed optionally by a RECEIVE DIAGNOSTIC  RESULTS
       command.  The former sends a Download microcode Control diagnostic page
       (dpage) and the latter fetches a Download microcode status dpage  which
       can be viewed as a report on the former command.

       The  default action (i.e. when the --mode=MO option is not given) is to
       fetch the Download microcode status dpage and decode it. This does  not
       require  the microcode (firmware) itself so the --in=FILE option is not

       The most recent reference for this utility is the draft SCSI  Enclosure
       Services 3 (SES-3) document T10/2149-D Revision 7 at http://www.t10.org
       .  Existing standards for SES and SES-2 are ANSI  INCITS  305-1998  and
       ANSI INCITS 448-2008 respectively.

       Most  other  support  for  SES  in this package (apart from downloading
       microcode) can be found in the sg_ses utility. Another way of download-
       ing  firmware to a SCSI device is with the WRITE BUFFER command defined
       in SPC-4, see the sg_write_buffer utility.

       Arguments to long options are mandatory for short options as well.

       -b, --bpw=CS
              where CS is the chunk size in bytes and should be a multiple  of
              4.  This will be the maximum number of bytes sent per SEND DIAG-
              NOSTIC command.  So if CS is less than the effective  length  of
              the  microcode  then multiple SEND DIAGNOSTIC commands are sent,
              each taking the next chunk from the read data and increasing the
              buffer  offset  field in the Download microcode control dpage by
              the appropriate amount. The default is a chunk size of  0  which
              is  interpreted as a very large number hence only one SEND DIAG-
              NOSTIC command will be sent.
              The number in CS can optionally be followed by ",act" or ",acti-
              vate".   In  this case after the microcode has been successfully
              sent to the DEVICE, an  additional  Download  microcode  control
              dpage  with  its mode set to "Activate deferred microcode" [0xf]
              is sent.

       -d, --dry-run
              the actual calls to perform SEND DIAGNOSTIC and RECEIVE DIAGNOS-
              TIC  RESULTS  commands are skipped when this option is given. No
              SCSI commands are sent to the DEVICE but it is still opened  and
              is  required  to be given.  A dummy device such as /dev/null (in
              Unix) can be used.
              This utility expects a "sensible" response to the RECEIVE  DIAG-
              NOSTIC  RESULTS  command  it sends (and will abort if it doesn't
              receive one). So this option supplies dummy responses  with  one
              primary  enclosure and three sub-enclosures. The dummy responses
              include good status values.

       -e, --ealsd
              exit after last SEND DIAGNOSTIC command. A SES device should not
              start  its  firmware  update immediately after the last received
              "chunk" of its firmware.  Rather it should wait  till  at  least
              one  RECEIVE  DIAGNOSTIC  RESULTS  command  is  sent to give the
              device a chance to report any error.  However  some  devices  do
              start  the firmware update immediately which causes the trailing
              RECEIVE DIAGNOSTIC RESULTS command to be held up  and  often  be
              aborted with a "target reset" error.
              This  option causes the trailing RECEIVE DIAGNOSTIC RESULTS com-
              mand to be skipped. This option would be typically used with the
              --bpw=CS option.
              Prior  to  version  1.10  of  this utility [20180112] this (i.e.
              skipping the last RECEIVE DIAGNOSTIC RESULTS  command)  was  the
              default action.

       -h, --help
              output  the usage message then exit. If used multiple times also
              prints the mode names and their acronyms.

       -i, --id=ID
              this option sets the BUFFER ID field in the  Download  microcode
              control  dpage. ID is a value between 0 (default) and 255 inclu-

       -I, --in=FILE
              read data from file FILE that will be sent with the  SEND  DIAG-
              NOSTIC  command.  If FILE is '-' then stdin is read until an EOF
              is detected (this is the same action as  --raw).  Data  is  read
              from the beginning of FILE except in the case when it is a regu-
              lar file and the --skip=SKIP option is given.

       -l, --length=LEN
              where LEN is the length, in bytes, of data to be written to  the
              device.   If  not  given  (and the length cannot be deduced from
              --in=FILE or --raw) then defaults to  zero.  If  the  option  is
              given and the length deduced from --in=FILE or --raw is less (or
              no data is provided), then bytes of 0xff are used as fill bytes.

       -m, --mode=MO
              this option sets the MODE. MO is a value  between  0  (which  is
              dmc_status  and the default) and 255 inclusive. Alternatively an
              abbreviation can be given. See the MODES section below. To  list
              the available mode abbreviations at run time give an invalid one
              (e.g. '--mode=xxx') or use the '-h' option.

       -N, --non
              allow for non-standard implementations that reset their Download
              microcode engine after a RECEIVE DIAGNOSTIC RESULTS command with
              the Download microcode status dpage is sent. When this option is
              given  sending  that  command  and  dpage combination is avoided
              unless an error has already occurred.

       -o, --offset=OFF
              this option  sets  the  BUFFER  OFFSET  field  in  the  Download
              microcode  control dpage. OFF is a value between 0 (default) and
              2**32-1 . It is a byte offset. This option  is  ignored  (and  a
              warning sent to stderr) if the --bpw=CS option is also given.

       -s, --skip=SKIP
              this option is only active when --in=FILE is given and FILE is a
              regular file, rather than stdin. Data is read starting  at  byte
              offset  SKIP  to  the  end  of  file  (or  the  amount  given by
              --length=LEN).  If not given the byte offset defaults to 0 (i.e.
              the start of the file).

       -S, --subenc=SEID
              SEID  is  the  sub-enclosure identify. It defaults to 0 which is
              the primary enclosure identifier.

       -t, --tlength=TLEN
              TLEN is the total length in bytes of the  microcode  to  be  (or
              being) downloaded. It defaults to 0 which is okay in most cases.
              This option only comes into play when TLEN is greater than  LEN.
              In  this  case  TLEN  is sent to the SES DEVICE so that it knows
              when it only receives LEN bytes from this  invocation,  that  it
              should  expect  more  to  be  sent  in  the near future (e.g. by
              another invocation). This option is only needed when sections of
              microcode are being sent in separate invocations of this utility
              (e.g. the microcode is spread across two files).

       -v, --verbose
              increase the level of verbosity, (i.e. debug output).

       -V, --version
              print the version string and then exit.

       Following is a list accepted by the MO argument of this utility.  First
       shown  is  an  acronym followed in square brackets by the corresponding
       decimal and hex values that may also be given for MO.

       dmc_status  [0, 0x0]
              Use RECEIVE DIAGNOSTIC RESULTS to fetch the  Download  microcode
              status dpage and print it out.

       dmc_offs  [6, 0x6]
              Download microcode with offsets and activate.

       dmc_offs_save  [7, 0x7]
              Download microcode with offsets, save, and activate.

       dmc_offs_defer  [14, 0xe]
              Download microcode with offsets, save, and defer activate.

       activate_mc  [15, 0xf]
              Activate deferred microcode. There is no follow-up RECEIVE DIAG-
              NOSTIC RESULTS to fetch  the  Download  microcode  status  dpage
              since the DEVICE might be resetting.

       Apart  from dmc_status, these are placed in the Download microcode mode
       field in the Download microcode control dpage. In the case of  dmc_sta-
       tus  the  Download  microcode  status dpage is fetched with the RECEIVE
       DIAGNOSTIC RESULTS command and decoded.

       Firstly, if it succeeds, this utility should stay  silent  and  return.
       Typically vendors will change the "revision" string (which is 4 charac-
       ters long) whenever they release new firmware. That can be seen in  the
       response  to  a  SCSI  INQUIRY command, for example by using the sg_inq
       utility.  It is possible that the  device  needs  to  be  power  cycled
       before  the  new  microcode becomes active. Also if mode dmc_offs_defer
       [0xe] is used to download the microcode, then another  invocation  with
       activate_mc may be needed.

       If  something  goes wrong, there will typically be messages printed out
       by this utility. The first thing to check is the  microcode  (firmware)
       file  itself.  Is  it  designed  for the device model; has it been cor-
       rupted, and if downgrading (i.e. trying to reinstate  older  firmware),
       does the vendor allow that?

       Getting  new  firmware  on a device is a delicate operation that is not
       always well defined by T10's standards and drafts. One might  speculate
       that  they are deliberately vague. In testing this utility one vendor's
       interpretation of the  standard  was  somewhat  surprising.  The  --non
       option  was  added  to  cope with their interpretation. So if the above
       suggestions don't help, try adding the --non option.

       See attributes(7) for descriptions of the following attributes:

       |Availability   | system/storage/sg3_utils |
       |Stability      | Pass-through uncommitted |

       This utility can handle a maximum size of 128  MB  of  microcode  which
       should be sufficient for most purposes. In a system that is memory con-
       strained, such large allocations of memory may fail.

       The user should be aware that most operating systems have limits on the
       amount  of  data  that can be sent with one SCSI command. In Linux this
       depends on the pass through mechanism used (e.g. block SG_IO or the  sg
       driver) and various setting in sysfs in the Linux lk 2.6/3 series (e.g.
       /sys/block/sda/queue/max_sectors_kb). Devices (i.e. logical units) also
       typically  have limits on the maximum amount of data they can handle in
       one command. These two limitations suggest that  modes  containing  the
       word  "offset"  together  with  the  --bpw=CS  option  are  required as
       firmware files get larger and larger. And CS can be  quite  small,  for
       example  4096  bytes,  resulting in many SEND DIAGNOSTIC commands being

       The exact error from the non-standard implementation was a sense key of
       ILLEGAL  REQUEST  and  an  asc/ascq  code of 0x26,0x0 which is "Invalid
       field in parameter list". If that is seen  try  again  with  the  --non

       Downloading incorrect microcode into a device has the ability to render
       that device inoperable. One would hope that the device vendor  verifies
       the data before activating it.

       A  long  (operating system) timeout of 7200 seconds is set on each SEND
       DIAGNOSTIC command.

       All numbers given with options are assumed  to  be  decimal.   Alterna-
       tively  numerical values can be given in hexadecimal preceded by either
       "0x" or "0X" (or has a trailing "h" or "H").

       Source code for open source software components in Oracle  Solaris  can
       be found at https://www.oracle.com/downloads/opensource/solaris-source-

       This    software    was    built    from    source     available     at
       https://github.com/oracle/solaris-userland.    The  original  community
       source was downloaded from  http://sg.danny.cz/sg/p/sg3_utils-1.46.tgz.

       Further information about this software can be found on the open source
       community website at http://sg.danny.cz/sg/sg3_utils.html.

       If  no  microcode/firmware  file is given then this utility fetches and
       decodes the Download microcode status dpage which could  possibly  show
       another  initiator  in  the  process of updating the microcode. Even if
       that is happening, fetching the status page should not cause any  prob-

         sg_ses_microcode /dev/sg3
       Download microcode status diagnostic page:
         number of secondary sub-enclosures: 0
         generation code: 0x0
          sub-enclosure identifier: 0 [primary]
            download  microcode  status:  No  download  microcode operation in
       progress [0x0]
            download microcode additional status: 0x0
            download microcode maximum size: 1048576 bytes
            download microcode expected buffer id: 0x0
            download microcode expected buffer id offset: 0

       The following sends new microcode/firmware to an enclosure.  Sending  a
       1.5  MB file in one command caused the enclosure to lock up temporarily
       and did not update the firmware. Breaking the firmware file into  4  KB
       chunks (an educated guess) was more successful:

         sg_ses_microcode -b 4k -m dmc_offs_save -I firmware.bin /dev/sg4

       The  firmware  update  occurred in the following enclosure power cycle.
       With a modern enclosure the Extended Inquiry VPD page gives indications
       in which situations a firmware upgrade will take place.

       The  exit status of sg_ses_microcode is 0 when it is successful. Other-
       wise see the sg3_utils(8) man page.

       Written by Douglas Gilbert.

       Report bugs to <dgilbert at interlog dot com>.

       Copyright (C) 2014-2018 Douglas Gilbert
       This software is distributed under a FreeBSD license. There is NO  war-
       ranty;  not  even  for MERCHANTABILITY or FITNESS FOR A PARTICULAR PUR-

       sg_ses, sg_write_buffer, sg_inq(sg3_utils)

sg3_utils-1.43                   January 2018              SG_SES_MICROCODE(8)