doc/sg_ses.8

.TH SG_SES "8" "October 2021" "sg3_utils\-1.47" SG3_UTILS
.SH NAME
sg_ses \- access a SCSI Enclosure Services (SES) device
.SH SYNOPSIS
.B sg_ses
[\fI\-\-all\fR] [\fI\-\-ALL\fR] [\fI\-\-descriptor=DES\fR]
[\fI\-\-dev\-slot\-num=SN\fR] [\fI\-\-eiioe=A_F\fR] [\fI\-\-filter\fR]
[\fI\-\-get=STR\fR] [\fI\-\-hex\fR] [\fI\-\-index=IIA\fR |
\fI\-\-index=TIA,II\fR] [\fI\-\-inner\-hex\fR] [\fI\-\-join\fR]
[\fI\-\-maxlen=LEN\fR] [\fI\-\-page=PG\fR] [\fI\-\-quiet\fR] [\fI\-\-raw\fR]
[\fI\-\-readonly\fR] [\fI\-\-sas\-addr=SA\fR] [\fI\-\-status\fR]
[\fI\-\-verbose\fR] [\fI\-\-warn\fR] \fIDEVICE\fR
.PP
.B sg_ses
\fI\-\-control\fR [\fI\-\-byte1=B1\fR] [\fI\-\-clear=STR\fR]
[\fI\-\-data=H,H...\fR] [\fI\-\-data=@FN\fR] [\fI\-\-descriptor=DES\fR]
[\fI\-\-dev\-slot\-num=SN\fR] [\fI\-\-index=IIA\fR | \fI\-\-index=TIA,II\fR]
[\fI\-\-mask\fR] [\fI\-\-maxlen=LEN\fR] [\fI\-\-nickname=SEN\fR]
[\fI\-\-nickid=SEID\fR]  [\fI\-\-page=PG\fR] [\fI\-\-readonly\fR]
[\fI\-\-sas\-addr=SA\fR] [\fI\-\-set=STR\fR] [\fI\-\-verbose\fR]
\fIDEVICE\fR
.PP
.B sg_ses
\fI\-\-data=@FN\fR \fI\-\-status\fR [\fI\-\-raw\fR \fI\-\-raw\fR]
[<all options from first form>]
.br
.B sg_ses
\fI\-\-inhex=FN\fR \fI\-\-status\fR [\fI\-\-raw\fR \fI\-\-raw\fR]
[<all options from first form>]
.PP
.B sg_ses
[\fI\-\-enumerate\fR] [\fI\-\-index=IIA\fR] [\fI\-\-list\fR] [\fI\-\-help\fR]
[\fI\-\-version\fR]
.SH DESCRIPTION
.\" Add any additional description here
.PP
Fetches management information from a SCSI Enclosure Service (SES) device.
This utility can also modify the state of a SES device. The \fIDEVICE\fR
should be a SES device which may be a dedicated enclosure services
processor in which case an INQUIRY response's Peripheral Device Type is
13 [0xd]. Alternatively it may be attached to another type of SCSI
device (e.g. a disk) in which case the EncServ bit is set in its INQUIRY
response.
.PP
If the \fIDEVICE\fR argument is given with no options then the names of all
diagnostic pages (dpages) supported are listed. Most, but not necessarily
all, of the named dpages are defined in the SES standards and drafts. The
most recent reference for this utility is the draft SCSI Enclosure Services
4 document T10/BSR INCITS 555 Revision 5 at https://www.t10.org . Existing
standards for SES, SES\-2 and SES\-3 are ANSI INCITS 305\-1998 and ANSI
INCITS 448\-2008 and ANSI INCITS 518\-2017 respectively.
.PP
SAS expanders typically have a SES device attached via a virtual port.
Some HBAs (SCSI initiators) choose to expose a SES device internally. That
means the SCSI subsystem on the host machine can see the SES device, but
devices connected to that HBA (e.g. a SAS expander) cannot see the HBA's
SES device. That internal SES device might report on the temperature(s)
of the HBA and whether anything is connected to its SCSI ports.
.PP
The first form shown in the synopsis is for fetching and decoding dpages or
fields from the SES \fIDEVICE\fR. A SCSI RECEIVE DIAGNOSTIC RESULTS command
is sent to the \fIDEVICE\fR to obtain each dpage response.  Rather than
decoding a fetched dpage, it may be output in hex or binary with the
\fI\-\-hex\fR or \fI\-\-raw \-\-raw\fR options.
.PP
The second form in the synopsis is for modifying dpages or fields held in
the SES \fIDEVICE\fR. A SCSI SEND DIAGNOSTIC command containing a "control"
dpage is sent to the \fIDEVICE\fR to cause changes. Changing the state of an
enclosure (e.g. requesting the "ident" (locate) LED to flash on a disk
carrier in an array) is typically done using a read\-modify\-write cycle.
See the section on CHANGING STATE below.
.PP
The third form in the synopsis has two equivalent invocations shown. They
decode the contents of a file (named \fIFN\fR) that holds a hexadecimal or
binary representation of one, or many, SES dpage responses. Typically an
earlier invocation of the first form of this utility with the '\-HHHH'
option would have generated that file. Since no SCSI commands are sent, the
\fIDEVICE\fR argument if given will be ignored.
.PP
The last form in the synopsis shows the options for providing command line
help (i.e. usage information), listing out dpage and field information tables
held by the utility (\fI\-\-enumerate\fR), or printing the version string
of this utility.
.PP
There is a web page discussing this utility at
https://sg.danny.cz/sg/sg_ses.html . Support for downloading microcode to
a SES device has been placed in a separate utility called sg_ses_microcode.
.PP
In the following sections "dpage" refers to a diagnostic page, either fetched
with a SCSI RECEIVE DIAGNOSTIC RESULTS command, sent to the \fIDEVICE\fR with
a SCSI SEND DIAGNOSTIC command, or fetched from data supplied by the
\fI\-\-data=\fR option.
.SH OPTIONS
Arguments to long options are mandatory for short options as well.
The options are arranged in alphabetical order based on the long
option name.
.TP
\fB\-a\fR, \fB\-\-all\fR
shows (almost) all status dpages, following references and presenting
the information as a long list whose indentation indicates the level
of nesting. This option is actually the same as \fI\-\-join\fR, see its
description for more information.
.br
If used twice, adds threshold elements to output (if they are available).
So it is the same as using \fI\-\-join\fRtwice.
.TP
\fB\-z\fR, \fB\-\-ALL\fR
shows (almost) all status dpages, following references and presenting
the information as a long list whose indentation indicates the level
of nesting. Also shows the threshold elements if they are available.
This option is the same as using  \fI\-\-join\fR rwice.
.TP
\fB\-b\fR, \fB\-\-byte1\fR=\fIB1\fR
some modifiable dpages may need byte 1 (i.e. the second byte) set. In the
Enclosure Control dpage, byte 1 contains the INFO, NON\-CRIT, CRIT and
UNRECOV bits. In the Subenclosure String Out, Subenclosure Nickname Control
and Download Microcode Control dpages, byte 1 is the Subenclosure identifier.
Active when the \fI\-\-control\fR and \fI\-\-data=H,H...\fR options are used
and the default value is 0. If the \fI\-\-clear=STR\fR or \fI\-\-set=STR\fR
option is used then the value read from byte 1 is written back to byte 1.
\fIB1\fR is in decimal unless it is prefixed by '0x' or '0X' (or has a
trailing 'h' or 'H').
.TP
\fB\-C\fR, \fB\-\-clear\fR=\fISTR\fR
Used to clear an element field in the Enclosure Control or Threshold Out
dpage. Must be used together with an indexing option to specify which element
is to be changed. The Enclosure Control dpage is assumed if the
\fI\-\-page=PG\fR option is not given. See the STR FORMAT and the CLEAR, GET,
SET sections below.
.TP
\fB\-c\fR, \fB\-\-control\fR
will send control information to the \fIDEVICE\fR via a SCSI SEND
DIAGNOSTIC command. Cannot give both this option and \fI\-\-status\fR.
The Enclosure Control, String Out, Threshold Out, Array Control (obsolete
in SES\-2), Subenclosure String Out, Subenclosure Nickname Control and
Download Microcode dpages can be set currently. This option is assumed if
either the \fI\-\-clear=STR\fR or \fI\-\-set=STR\fR option is given.
.TP
\fB\-d\fR, \fB\-\-data\fR=\fIH,H...\fR
permits a string of comma separated (ASCII) hex bytes to be specified (limit
1024). A (single) space separated string of hex bytes is also allowed but
the list needs to be in quotes. This option allows the parameters to a
control dpage to be specified. The string given should not include the first 4
bytes (i.e. page code and length). See the DATA SUPPLIED section below.
.TP
\fB\-d\fR, \fB\-\-data\fR=\-
reads one or more data strings from stdin, limit almost 2**16 bytes. stdin
may provide ASCII hex as a comma separated list (i.e. as with the
\fI\-\-data=H,H...\fR option). Additionally spaces, tabs and line feeds are
permitted as separators from stdin . Stops reading stdin when an EOF is
detected. See the DATA SUPPLIED section below.
.TP
\fB\-d\fR, \fB\-\-data\fR=@\fIFN\fR
reads one or more data strings from the file called \fIFN\fR, limit almost
2**16 bytes. The contents of the file is decoded in the same fashion as
stdin described in the previous option. See the DATA SUPPLIED section below.
.TP
\fB\-D\fR, \fB\-\-descriptor\fR=\fIDES\fR
where \fIDES\fR is a descriptor name (string) as found in the Element
Descriptor dpage. This is a medium level indexing alternative to the low
level \fI\-\-index=\fR options. If the descriptor name contains a space then
\fIDES\fR needs to be surrounded by quotes (single or double) or the space
escaped (e.g. preceded by a backslash). See the DESCRIPTOR NAME, DEVICE SLOT
NUMBER AND SAS ADDRESS section below.
.TP
\fB\-x\fR, \fB\-\-dev\-slot\-num\fR=\fISN\fR, \fB\-\-dsn\fR=\fISN\fR
where \fISN\fR is a device slot number found in the Additional Element Status
dpage. Only entries for FCP and SAS devices (with EIP=1) have device slot
numbers. \fISN\fR must be a number in the range 0 to 255 (inclusive). 255 is
used to indicate there is no corresponding device slot. This is a medium level
indexing alternative to the low level \fI\-\-index=\fR options. See the
DESCRIPTOR NAME, DEVICE SLOT NUMBER AND SAS ADDRESS section below.
.TP
\fB\-E\fR, \fB\-\-eiioe\fR=\fIA_F\fR
\fIA_F\fR is either the string 'auto' or 'force'. There was some fuzziness
in the interpretation of the 'element index' field in the Additional Element
Status (AES) dpage between SES\-2 and SES\-3. The EIIOE bit was introduced to
resolve the problem but not all enclosures have caught up. In the SES\-3
revision 12 draft the EIIOE bit was expanded to a 2 bit EIIOE field.
Using '\-\-eiioe=force' will decode the AES dpage as if the EIIOE field is set
to 1.  Using '\-\-eiioe=auto' will decode the AES dpage as if the EIIOE field
is set to 1 if the first AES descriptor has its EIP bit set and its element
index field is 1 (in other words a heuristic to guess whether the EIIOE field
should be set to 1 or 0).
.br
If the enclosure sets the actual EIIOE field to 1 or more then this option has
no effect. It is recommended that HP JBOD users set \-\-eiioe=auto .
.TP
\fB\-e\fR, \fB\-\-enumerate\fR
enumerate all known diagnostic page (dpage) names and SES elements that this
utility recognizes plus the abbreviations accepted by this utility. Ignores
\fIDEVICE\fR if it is given. Essentially it is dumping out tables held
internally by this utility.
.br
If \fI\-\-enumerate\fR is given twice, then the recognised acronyms for the
\fI\-\-clear=STR\fR, \fI\-\-get=STR\fR and \fI\-\-set=STR\fR options are
listed. The utility exits after listing this information, so most other
options and \fIDEVICE\fR are ignored. Since there are many acronyms for
the Enclosure Control/Status dpage then the output can be further restricted
by giving the \fI\-\-index=IIA\fR option (e.g. "sg_ses \-ee \-I ts" to only
show the acronyms associated with the Enclosure Control/Status dpage's
Temperature Sensor Element Type).
.TP
\fB\-f\fR, \fB\-\-filter\fR
cuts down on the amount of output from the Enclosure Status dpage and the
Additional Element Status dpage. When this option is given, any line which
has all its binary flags cleared (i.e. 0) is filtered out (i.e.  ignored).
If a line has some other value on it (e.g. a temperature) then it is output.
When this option is used twice only elements associated with the "status=ok"
field (in the Enclosure status dpage) are output. The \fI\-\-filter\fR option
is useful for reducing the amount of output generated by the \fI\-\-join\fR
option.
.TP
\fB\-G\fR, \fB\-\-get\fR=\fISTR\fR
Used to read a field in a status element. Must be used together with a an
indexing option to specify which element is to be read. By default the
Enclosure Status dpage is read, the only other dpages that can be read are the
Threshold In and Additional Element Status dpages. If a value is found it is
output in decimal to stdout (by default) or in hexadecimal preceded by "0x"
if the \fI\-\-hex\fR option is also given. See the STR FORMAT and the CLEAR,
GET, SET sections below.
.TP
\fB\-h\fR, \fB\-\-help\fR
output the usage message then exit. Since there is a lot of information,
it is split into two pages. The most important is shown on the first page.
Use this option twice (e.g. '\-hh') to output the second page. Note: the
\fI\-\-enumerate\fR option might also be viewed as a help or usage type
option. And like this option it has a "given twice" form: '\-ee'.
.TP
\fB\-H\fR, \fB\-\-hex\fR
If the \fI\-\-get=STR\fR option is given then output the value found (if
any) in hexadecimal, with a leading "0x". Otherwise output the response
in hexadecimal; with trailing ASCII if given once, without it if given
twice, and simple hex if given three or more times. Ignored when all
elements from several dpages are being accessed (e.g. when the \fI\-\-join\fR
option is used). Also see the \fI\-\-raw\fR option which may be used
with this option.
.br
To dump one of more dpage responses to stdout in ASCII parsable hexadecimal
use \fI\-HHH\fR or \fI\-HHHH\fR. The triple H form only outputs hexadecimals
which is fine for a single dpage response. When all dpages are dumped (e.g.
with \fI\-\-page=all\fR) then the quad H form adds the name of each dpage
following a hash mark ('#'). The \fI\-\-data=\fR option parser ignores
everything from and including a hash mark to the end of the line. Hence the
output of the quad H form is still parsable plus it is easier for users to
view and possibly edit. \fI\-HHHHH\fR (that is 5) adds the page code in
hex after the page's name in the comment.
.TP
\fB\-I\fR, \fB\-\-index\fR=\fIIIA\fR
where \fIIIA\fR is either an individual index (II) or an Element type
abbreviation (A). See the INDEXES section below. If the \fI\-\-page=PG\fR
option is not given then the Enclosure Status (or Control) dpage is assumed.
May be used with the \fI\-\-join\fR option or one of the \fI\-\-clear=STR\fR,
\fI\-\-get=STR\fR or \fI\-\-set=STR\fR options. To enumerate the available
Element type abbreviations use the \fI\-\-enumerate\fR option.
.TP
\fB\-I\fR, \fB\-\-index\fR=\fITIA,II\fR
where \fITIA,II\fR is an type header index (TI) or Element type
abbreviation (A) followed by an individual index (II). See the INDEXES section
below. If the \fI\-\-page=PG\fR option is not given then the Enclosure
Status (or Control) dpage is assumed. May be used with the \fI\-\-join\fR
option or one of the \fI\-\-clear=STR\fR, \fI\-\-get=STR\fR or
\fI\-\-set=STR\fR options. To enumerate the available Element type
abbreviations use the \fI\-\-enumerate\fR option.
.TP
\fB\-X\fR, \fB\-\-inhex\fR=\fIFN\fR
where \fIFN\fR is a filename. It has the equivalent action of the
\fI\-\-data=@FN\fR option. If \fIFN\fR is '\-' then stdin is read. This
option has been given for compatibility with other utilities in this
package that use \fI\-\-inhex=FN\fR (or \fI\-\-in=FN\fR) is a similar
way. See the "FORMAT OF FILES CONTAINING ASCII HEX" section in the
sg3_utils manpage for more information.
.TP
\fB\-i\fR, \fB\-\-inner\-hex\fR
the outer levels of a status dpage are decoded and printed out but the
innermost level (e.g. the Element Status Descriptor) is output in hex. Also
active with the Additional Element Status and Threshold In dpages. Can be
used with an indexing option and/or \fI\-\-join\fR options.
.TP
\fB\-j\fR, \fB\-\-join\fR
group elements from the Element Descriptor, Enclosure Status and Additional
Element Status dpages. If this option is given twice then elements from the
Threshold In dpage are also grouped. The order is dictated by the Configuration
dpage.
.br
There can be a bewildering amount of information in the "join" output. The
default is to output everything. Several additional options are provided to
cut down the amount displayed. If the indexing options is given, only the
matching elements and their associated fields are output. The \fI\-\-filter\fR
option (see its description) can be added to reduce the amount of output.
Also "\-\-page=aes" (or "\-p 0xa") can be added to suppress the output of
rows that don't have a "aes" dpage component. See the INDEXES and DESCRIPTOR
NAME, DEVICE SLOT NUMBER AND SAS ADDRESS sections below.
.TP
\fB\-l\fR, \fB\-\-list\fR
This option is equivalent to \fI\-\-enumerate\fR. See that option.
.TP
\fB\-M\fR, \fB\-\-mask\fR
When modifying elements, the default action is a read (status element),
mask, modify (based on \fI\-\-clear=STR\fR or \fI\-\-set=STR\fR) then write
back as the control element. The mask step is new in sg_ses version 1.98
and is based on what is allowable (and in the same location) in draft SES\-3
revision 6. Those masks may evolve, as they have in the past. This option
re\-instates the previous logic which was to ignore the mask step. The
default action (i.e. without this option) is to perform the mask step in
the read\-mask\-modify\-write sequence.
.TP
\fB\-m\fR, \fB\-\-maxlen\fR=\fILEN\fR
\fILEN\fR is placed in the ALLOCATION LENGTH field of the SCSI RECEIVE
DIAGNOSTIC RESULTS commands sent by the utility. It represents the maximum
size of data the SES device can return (in bytes). It cannot exceed 65535
and defaults to 65532 (bytes). Some systems may not permit such large sizes
hence the need for this option. If \fILEN\fR is less than 0 or greater than
65535 then an error is generated. If \fILEN\fR is 0 then the default value
is used, otherwise if it is less than 4 then it is ignored (and a warning is
sent to stderr).
.TP
\fB\-n\fR, \fB\-\-nickname\fR=\fISEN\fR
where \fISEN\fR is the new Subenclosure Nickname. Only the first 32
characters (bytes) of \fISEN\fR are used, if more are given they are
ignored. See the SETTING SUBENCLOSURE NICKNAME section below.
.TP
\fB\-N\fR, \fB\-\-nickid\fR=\fISEID\fR
where \fISEID\fR is the Subenclosure identifier that the new
Nickname (\fISEN\fR) will be applied to. So \fISEID\fR must be an existing
Subenclosure identifier. The default value is 0 which is the
main enclosure.
.TP
\fB\-p\fR, \fB\-\-page\fR=\fIPG\fR
where \fIPG\fR is a dpage abbreviation or code (a number). If \fIPG\fR
starts with a digit it is assumed to be in decimal unless prefixed by
0x for hex. Valid range is 0 to 255 (0x0 to 0xff) inclusive. Default is
dpage 'sdp' which is page_code 0 (i.e. "Supported Diagnostic Pages") if
no other options are given.
.br
Page code 0xff or abbreviation "all" is not a real dpage (as the highest
real dpage is 0x3f) but instead causes all dpages whose page code is 0x2f
or less to be output. This can be used with either the \fI\-HHHH\fR or
\fI\-rr\fR to send either hexadecimal ASCII or binary respectively to
stdout.
.br
To list the available dpage abbreviations give "xxx" for \fIPG\fR; the same
information can also be found with the \fI\-\-enumerate\fR option.
.TP
\fB\-q\fR, \fB\-\-quiet\fR
this suppresses the number of warnings and messages output. The exit status
of the utility is unaffected by this option.
.TP
\fB\-r\fR, \fB\-\-raw\fR
outputs the chosen status dpage in ASCII hex in a format suitable for a
later invocation using the \fI\-\-data=\fR option. A dpage less its first
4 bytes (page code and length) is output. When used twice (e.g. \fI\-rr\fR)
the full dpage contents is output in binary to stdout.
.br
when \fI\-rr\fR is used together with the \fI\-\-data=\-\fR or
\fI\-\-data=@FN\fR then stdin or file FN is decoded as a binary stream that
continues to be read until an end of file (EOF). Once that data is read then
the internal raw option is cleared to 0 so the output is not effected. So
the \fI\-rr\fR option either changes how the input or output is treated,
but not both.
.TP
\fB\-R\fR, \fB\-\-readonly\fR
open the \fIDEVICE\fR read\-only (e.g. in Unix with the O_RDONLY flag).
The default is to open it read\-write.
.TP
\fB\-A\fR, \fB\-\-sas\-addr\fR=\fISA\fR
this is an indexing method for SAS end devices (e.g. SAS disks). The utility
will try to find the element or slot in the Additional Element Status dpage
whose SAS address matches \fISA\fR. For a SAS disk or tape that SAS address
is its target port identifier for the port connected to that element or slot.
Most SAS disks and tapes have two such target ports, usually numbered
consecutively.
.br
SATA devices in a SAS enclosure often receive "manufactured" target port
identifiers from a SAS expander; typically will have a SAS address close to,
but different from, the SAS address of the expander itself. Note that this
manufactured target port identifier is different from a SATA disk's WWN.
.br
\fISA\fR is a hex number that is up to 8 digits long. It may have a
leading '0x' or '0X' or a trailing 'h' or 'H'. This option is a medium level
 indexing alternative to the low level \fI\-\-index=\fR options.
See the DESCRIPTOR NAME, DEVICE SLOT NUMBER AND SAS ADDRESS section below.
.TP
\fB\-S\fR, \fB\-\-set\fR=\fISTR\fR
Used to set an element field in the Enclosure Control or Threshold Out dpage.
Must be used together with an indexing option to specify which element is to
be changed. The Enclosure Control dpage is assumed if the \fI\-\-page=PG\fR
option is not given. See the STR FORMAT and CLEAR, GET, SET sections below.
.TP
\fB\-s\fR, \fB\-\-status\fR
will fetch dpage from the \fIDEVICE\fR via a SCSI RECEIVE DIAGNOSTIC RESULTS
command (or from \fI\-\-data=@FN\fR). In the absence of other options that
imply modifying a dpage (e.g.  \fI\-\-control\fR or \fI\-\-set=STR\fR) then
\fI\-\-status\fR is assumed, except when the \fI\-\-data=\fR option is given.
When the \fI\-\-data=\fR option is given there is no default action: either
the \fI\-\-control\fR or this option must be given to distinguish between
the two different ways that data will be treated.
.TP
\fB\-v\fR, \fB\-\-verbose\fR
increase the level of verbosity. For example when this option is given four
times (in which case the short form is more convenient: '\-vvvv') then if
the internal join array has been generated then it is output to stderr in
a form suitable for debugging.
.TP
\fB\-V\fR, \fB\-\-version\fR
print the version string and then exit.
.TP
\fB\-w\fR, \fB\-\-warn\fR
warn about certain irregularities with warnings sent to stderr. The join
is a complex operation that relies on information from several dpages to be
synchronized. The quality of SES devices vary and to be fair, the
descriptions from T10 drafts and standards have been tweaked several
times (see the EIIOE field) in order to clear up confusion.
.SH INDEXES
An enclosure can have information about its disk and tape drives plus other
supporting components like power supplies spread across several dpages.
Addressing a specific element (overall or individual) within a dpage is
complicated. This section describes low level indexing (i.e. choosing a
single element (or a group of related elements) from a large number of
elements). If available, the medium level indexing described in the
following section (DESCRIPTOR NAME, DEVICE SLOT NUMBER AND SAS ADDRESS)
might be simpler to use.
.PP
The Configuration dpage is key to low level indexing: it contains a list
of "type headers", each of which contains an Element type (e.g. Array
Device Slot), a Subenclosure identifier (0 for the primary enclosure) and
a "Number of possible elements". Corresponding to each type header, the
Enclosure Status dpage has one "overall" element plus "Number of possible
elements" individual elements all of which have the given Element type. For
some Element types the "Number of possible elements" will be 0 so the
Enclosure Status dpage has only one "overall" element corresponding to that
type header. The Element Descriptor dpage and the Threshold (In and Out)
dpages follow the same pattern as the Enclosure Status dpage.
.PP
The numeric index corresponding to the overall element is "\-1". If the
Configuration dpage indicates a particular element type has "n" elements
and n is greater than 0 then its indexes range from 0 to n\-1 .
.PP
The Additional Element Status dpage is a bit more complicated. It has
entries for "Number of possible elements" of certain Element types. It
does not have entries corresponding to the "overall" elements. To make
the correspondence a little clearer each descriptor in this dpage optionally
contains an "Element Index Present" (EIP) indicator. If EIP is set then each
element's "Element Index" field refers to the position of the corresponding
element in the Enclosure Status dpage.
.PP
Addressing a single overall element or a single individual element is done
with two indexes: TI and II. Both are origin 0. TI=0 corresponds to the
first type header entry which must be a Device Slot or Array Device Slot
Element type (according to the SES\-2 standard). To address the corresponding
overall instance, II is set to \-1, otherwise II can be set to the individual
instance index. As an alternative to the type header index (TI), an Element
type abbreviation (A) optionally followed by a number (e.g. "ps" refers to
the first Power Supply Element type; "ps1" refers to the second) can be
given.
.PP
One of two command lines variants can be used to specify indexes:
\fI\-\-index=TIA,II\fR where \fITIA\fR is either an type header index (TI)
or an Element type abbreviation (A) (e.g. "ps" or "ps1"). \fIII\fR is either
an individual index or "\-1" to specify the overall element. The second
variant is \fI\-\-index=IIA\fR where \fIIIA\fR is either an individual
index (II) or an Element type abbreviation (A). When \fIIIA\fR is an
individual index then the option is equivalent to \fI\-\-index=0,II\fR. When
\fIIIA\fR is an Element type abbreviation then the option is equivalent to
\fI\-\-index=A,\-1\fR.
.PP
Wherever an individual index is applicable, it can be replaced by an
individual index range. It has the form: <first_ii>\-<last_ii>. For
example: '3\-5' will select individual indexes 3, 4 and 5 .
.PP
To cope with vendor specific Element types (whose type codes should be in
the range 128 to 255) the Element type code can be given as a number with
a leading underscore. For example these are equivalent: \fI\-\-index=arr\fR
and \fI\-\-index=_23\fR since the Array Device Slot Element type code is 23.
Also \fI\-\-index=ps1\fR and \fI\-\-index=_2_1\fR are equivalent.
.PP
Another example: if the first type header in the Configuration dpage has
has Array Device Slot Element type then \fI\-\-index=0,\-1\fR is
equivalent to \fI\-\-index=arr\fR. Also \fI\-\-index=arr,3\fR is equivalent
to \fI\-\-index=3\fR.
.PP
The \fI\-\-index=\fR options  can be used to reduce the amount of
output (e.g. only showing the element associated with the second 12 volt
power supply). They may also be used together with with the
\fI\-\-clear=STR\fR, \fI\-\-get=STR\fR and \fI\-\-set=STR\fR options which
are described in the STR section below.
.SH DESCRIPTOR NAME, DEVICE SLOT NUMBER AND SAS ADDRESS
The three options: \fI\-\-descriptor=DES\fR, \fI\-\-dev\-slot\-num=SN\fR
and \fI\-\-sas\-addr=SA\fR allow medium level indexing, as an alternative
to the low level \fI\-\-index=\fR options. Only one of the three options
can be used in an invocation. Each of the three options implicitly set the
\fI\-\-join\fR option since they need either the Element Descriptor dpage
or the Additional Element Status dpage as well as the dpages needed by the
\fI\-\-index=\fR option.
.PP
These medium level indexing options need support from the SES device and
that support is optional. For example the \fI\-\-descriptor=DES\fR needs
the Element Descriptor dpage provided by the SES device however that is
optional. Also the provided descriptor names need to be useful, and having
descriptor names which are all "0" is not very useful. Also some
elements (e.g. overall elements) may not have descriptor names.
.PP
These medium level indexing options can be used to reduce the amount of
output (e.g. only showing the elements related to device slot number 3).
They may also be used together with with the \fI\-\-clear=STR\fR,
\fI\-\-get=STR\fR and \fI\-\-set=STR\fR options which are described in the
following section. Note that even if a field can be set (e.g. "do not
remove" (dnr)) and that field can be read back with \fI\-\-get=STR\fR
confirming that change, the disk array may still ignore it (e.g. because it
does not have the mechanism to lock the disk drawer).
.SH STR FORMAT
The \fISTR\fR operands of the \fI\-\-clear=STR\fR, \fI\-\-get=STR\fR and
\fI\-\-set=STR\fR options all have the same structure. There are two forms:
.br
      <acronym>[=<value>]
.br
      <start_byte>:<start_bit>[:<num_bits>][=<value>]
.PP
The <acronym> is one of a list of common fields (e.g. "ident" and "fault")
that the utility converts internally into the second form. The <start_byte>
is usually in the range 0 to 3, the <start_bit> must be in the range 0 to
7 and the <num_bits> must be in the range 1 to 64 (default 1). The
number of bits are read in the left to right sense of the element tables
shown in the various SES draft documents. For example the 8 bits of
byte 2 would be represented as 2:7:8 with the most significant bit being
2:7 and the least significant bit being 2:0 .
.PP
The <value> is optional but is ignored if provided to \fI\-\-get=STR\fR.
For \fI\-\-set=STR\fR the default <value> is 1 while for \fI\-\-clear=STR\fR
the default value is 0 . <value> is assumed to be decimal, hexadecimal
values can be given in the normal fashion.
.PP
The supported list of <acronym>s can be viewed by using the
\fI\-\-enumerate\fR option twice (or "\-ee").
.SH CLEAR, GET, SET
The \fI\-\-clear=STR\fR, \fI\-\-get=STR\fR and \fI\-\-set=STR\fR options can
be used up to 8 times in the same invocation. Any <acronym>s used in the
\fISTR\fR operands must refer to the same dpage.
.PP
When multiple of these options are used (maximum: 8), they are applied in the
order in which they appear on the command line. So if options contradict each
other, the last one appearing on the command line will be enforced. When
there are multiple \fI\-\-clear=STR\fR and \fI\-\-set=STR\fR options, then
the dpage they refer to is only written after the last one.
.SH DATA SUPPLIED
This section describes the two scenarios that can occur when the
\fI\-\-data=\fR option is given. These scenarios are the same irrespective
of whether the argument to the \fI\-\-data=\fR option is a string of
hex bytes on the command line, stdin (indicated by \fI\-\-data=\-\fR) or
names a file (e.g. \fI\-\-data=@thresh_in_dpage.hex\fR).
.PP
The first scenario is flagged by the \fI\-\-control\fR option. It uses the
supplied data to build a 'control' dpage that will be sent to the
\fIDEVICE\fR using the SCSI SCSI SEND DIAGNOSTIC command. The supplied dpage
data should not include its first 4 bytes. Those 4 bytes are added by this
utility using the \fI\-\-page=PG\fR option with \fIPG\fR placed at byte
offset 0). If needed, the \fI\-\-byte1=B1\fR option sets byte offset 1,
else 0 is placed in that position. The number of bytes decoded from the data
provided (i.e. its length) goes into byte offsets 2 and 3.
.PP
The second scenario is flagged by the \fI\-\-status\fR option. It decodes
the supplied data assuming that it represents the response to one or more
SCSI RECEIVE DIAGNOSTIC RESULTS commands. Those responses have typically
been captured from some earlier invocation(s) of this utility. Those earlier
invocations could use the '\-HHH' or '\-HHHH' option and file redirection to
capture that response (or responses) in hexadecimal. The supplied dpage
response data is decoded according to the other command line options. For
example the \fI\-\-join\fR option could be given and that would require the
data from multiple dpages typically:  Configuration, Enclosure status,
Element descriptor and Additional element status dpages. If in doubt use
\fI\-\-page=all\fR in the capture phase; having more dpages than needed
is not a problem.
.PP
By default the user supplied data is assumed to be ASCII hexadecimal in
lines that don't exceed 512 characters. Anything on a line from and
including a hash mark ('#') to the end of line is ignored. An end of
line can be a LF or CR,LF and blank lines are ignored. Each separated
pair (or single) hexadecimal digits represent a byte (and neither a
leading '0x' nor a trailing 'h' should be given). Separators are either
space, tab, comma or end of line.
.PP
Alternatively binary can be used and this is flagged by the '\-rr' option.
The \fI\-\-data=H,H...\fR form cannot use binary values for the 'H's, only
ASCII hexadecimal. The other two forms (\fI\-\-data=\-\fR and
\fI\-\-data=@FN\fR) may contain binary data. Note that when the '\-rr'
option is used with \fI\-\-data=@FN\fR that it only changes the
interpretation of the input data, it does not change the decoding and output
representation.
.SH CHANGING STATE
This utility has various techniques for changing the state of a SES device.
As noted above this is typically a read\-modify\-write type operation.
Most modifiable dpages have a "status" (or "in") page that can be read, and
a corresponding "control" (or "out") dpage that can be written back to change
the state of the enclosure.
.PP
The lower level technique provided by this utility involves outputting
a "status" dpage in hex with \fI\-\-raw\fR. Then a text editor can be used
to edit the hex (note: to change an Enclosure Control descriptor the SELECT
bit needs to be set). Next the control dpage data can fed back with the
\fI\-\-data=H,H...\fR option together with the \fI\-\-control\fR option;
the \fI\-\-byte1=B1\fR option may need to be given as well.
.PP
Changes to the Enclosure Control dpage (and the Threshold Out dpage) can be
done at a higher level. This involves choosing a dpage (the default in this
case is the Enclosure Control dpage). Next choose an individual or overall
element index (or name it with its Element Descriptor string). Then give
the element's name (e.g. "ident" for RQST IDENT) or its position within that
element (e.g. in an Array Device Slot Control element RQST IDENT is byte 2,
bit 1 and 1 bit long ("2:1:1")). Finally a value can be given, if not the
value for \fI\-\-set=STR\fR defaults to 1 and for \fI\-\-clear=STR\fR
defaults to 0.
.SH SETTING SUBENCLOSURE NICKNAME
The format of the Subenclosure Nickname control dpage is different from its
corresponding status dpage. The status dpage reports all Subenclosure
Nicknames (and Subenclosure identifier 0 is the main enclosure) while the
control dpage allows only one of them to be changed. Therefore using the
\fB\-\-data\fR option technique to change a Subenclosure nickname is
difficult (but still possible).
.PP
To simplify changing a Subenclosure nickname the \fI\-\-nickname=SEN\fR and
\fI\-\-nickid=SEID\fR options have been added. If the \fISEN\fR string
contains spaces or other punctuation, it should be quoted: surrounded by
single or double quotes (or the offending characters escaped). If the
\fI\-\-nickid=SEID\fR is not given then a Subenclosure identifier of 0 is
assumed. As a guard the \fI\-\-control\fR option must also be given. If
the \fI\-\-page=PG\fR option is not given then \fI\-\-page=snic\fR is
assumed.
.PP
When \fI\-\-nickname=SEN\fR is given then the Subenclosure Nickname Status
dpage is read to obtain the Generation Code field. That Generation Code
together with no more than 32 bytes from the Nickname (\fISEN\fR) and the
Subenclosure Identifier (\fISEID\fR) are written to the Subenclosure Nickname
Control dpage.
.PP
There is an example of changing a nickname in the EXAMPLES section below.
.SH NVME ENCLOSURES
Support has been added to sg_ses (actually, its underlying library) for
NVMe (also known as NVM Express) Enclosures. It can be considered
experimental in sg3_utils package version 1.43 and sg_ses version 2.34 .
.PP
This support is based on a decision by NVME\-MI (Management Interface)
developers to support the SES\-3 standard. This was facilitated by adding
NVME\-MI SES Send and SES Receive commands that tunnel dpage contents as
used by SES.
.SH NOTES
This utility can be used to fetch arbitrary (i.e. non SES) dpages (using
the SCSI READ DIAGNOSTIC command). To this end the \fI\-\-page=PG\fR and
\fI\-\-hex\fR options would be appropriate. Non\-SES dpages can be sent to
a device with the sg_senddiag utility.
.PP
The most troublesome part of the join operation is associating Additional
Element Status descriptors correctly. At least one SES device vendor has
misinterpreted the SES\-2 standard, specifically with its "element index"
field interpretation. The code in this utility interprets the "element
index" field as per the SES\-2 standard and if that yields an inappropriate
Element type, adjusts its indexing to follow that vendor's
misinterpretation. The SES\-3 drafts have introduced the EIIOE (Element
Index Includes Overall Elements) bit which later became a 2 bit field to
resolve this ambiguity. See the \fI\-\-eiioe=A_F\fR option.
.PP
In draft SES\-3 revision 5 the "Door Lock" element name was changed to
the "Door" (and an OPEN field was added to the status element). As a
consequence the former 'dl' element type abbreviation has been changed
to 'do'.
.PP
Some RAID controllers hide SES device nodes from the host Operating System.
It has been reported that some MegaRAID controllers do this and the
following command is needed to expose them:
.PP
   perccli /cx set backplane expose=<on/off>
.PP
where perccli is Dell's version of BroadCom's (LSI) storcli utility.
.PP
There is a related command set called SAF\-TE (SCSI attached fault\-tolerant
enclosure) for enclosure (including RAID) status and control. SCSI devices
that support SAF\-TE report "Processor" peripheral device type (0x3) in their
INQUIRY response. See the sg_safte utility in this package or the
safte\-monitor utility on the Internet.
.PP
The internal join array is statically allocated and its size is controlled
by the MX_JOIN_ROWS define. Its current value is 520.
.SH EXAMPLES
Examples can also be found at https://sg.danny.cz/sg/sg_ses.html
.PP
The following examples use Linux device names. For suitable device names
in other supported Operating Systems see the sg3_utils(8) man page.
.PP
To view the supported dpages:
.PP
   sg_ses /dev/bsg/6:0:2:0
.PP
To view the Configuration Diagnostic dpage:
.PP
   sg_ses \-\-page=cf /dev/bsg/6:0:2:0
.PP
To view the Enclosure Status dpage:
.PP
   sg_ses \-\-page=es /dev/bsg/6:0:2:0
.PP
To get the (attached) SAS address of that device (which is held in the
Additional Element Sense dpage (dpage 10)) printed on hex:
.PP
   sg_ses \-p aes \-D ArrayDevice07 \-G at_sas_addr \-H /dev/sg3
.PP
To collate the information in the Enclosure Status, Element Descriptor
and Additional Element Status dpages the \fI\-\-join\fR option can be used:
.PP
   sg_ses \-\-join /dev/sg3
.PP
This will produce a lot of output. To filter out lines that don't contain
much information add the \fI\-\-filter\fR option:
.PP
   sg_ses \-\-join \-\-filter /dev/sg3
.PP
Fields in the various elements of the Enclosure Control and Threshold dpages
can be changed with the \fI\-\-clear=STR\fR and \fI\-\-set=STR\fR
options. [All modifiable dpages can be changed with the \fI\-\-raw\fR and
\fI\-\-data=H,H...\fR options.] The following example looks at making
the "ident" LED (also called "locate") flash on "ArrayDevice07" which is a
disk (or more precisely the carrier drawer the disk is in):
.PP
   sg_ses \-\-index=7 \-\-set=2:1:1 /dev/sg3
.PP
If the Element Descriptor diagnostic dpage shows that "ArrayDevice07" is
the descriptor name associated with element index 7 then this invocation
is equivalent to the previous one:
.PP
   sg_ses \-\-descriptor=ArrayDevice07 \-\-set=2:1:1 /dev/sg3
.PP
Further the byte 2, bit 1 (for 1 bit) field in the Array Device Slot Control
element is RQST IDENT for asking a disk carrier to flash a LED so it can
be located. In this case "ident" (or "locate") is accepted as an acronym
for that field:
.PP
   sg_ses \-\-descriptor=ArrayDevice07 \-\-set=ident /dev/sg3
.PP
To stop that LED flashing:
.PP
   sg_ses \-\-dev\-slot\-num=7 \-\-clear=ident /dev/sg3
.PP
The above assumes the descriptor name 'ArrayDevice07' corresponds to device
slot number 7.
.PP
Now for an example of a more general but lower level technique for changing
a modifiable diagnostic dpage. The String (In and Out) diagnostics dpage is
relatively simple (compared with the Enclosure Status/Control dpage). However
the use of this lower level technique is awkward involving three steps: read,
modify then write. First check the current String (In) dpage contents:
.PP
   sg_ses \-\-page=str /dev/bsg/6:0:2:0
.PP
Now the "read" step. The following command will send the contents of the
String dpage (from byte 4 onwards) to stdout. The output will be in ASCII
hex with pairs of hex digits representing a byte, 16 pairs per line,
space separated. The redirection puts stdout in a file called "t":
.PP
   sg_ses \-\-page=str \-\-raw /dev/bsg/6:0:2:0 > t
.PP
Then with the aid of the SES\-3 document (in revision 3: section 6.1.6)
use your favourite editor to change t. The changes can be sent to the
device with:
.PP
   sg_ses \-\-page=str \-\-control \-\-data=\- /dev/bsg/6:0:2:0 < t
.PP
If the above is successful, the String dpage should have been changed. To
check try:
.PP
   sg_ses \-\-page=str /dev/bsg/6:0:2:0
.PP
To change the nickname on the main enclosure:
.PP
   sg_ses \-\-nickname='1st enclosure' \-\-control /dev/bsg/6:0:2:0
.PP
To capture the whole state of an enclosure (from a SES perspective) for
later analysis, this can be done:
.PP
   sg_ses \-\-page=all \-HHHH /dev/sg5 > enc_sg5_all.hex
.PP
Note that if there are errors or warnings they will be sent to stderr so
they will appear on the command line (since only stdout is redirected).
A text editor could be used to inspect enc_sg5_all.hex . If all looks in
order at some later time, potentially on a different machine where
enc_sg5_all.hex has been copied, a "join" could be done. Note that join
reflects the state of the enclosure when the capture was done.
.PP
   sg_ses \-\-data=@enc_sg5_all.hex \-\-status \-\-join
.SH EXIT STATUS
The exit status of sg_ses is 0 when it is successful. Otherwise see
the sg3_utils(8) man page.
.SH AUTHORS
Written by Douglas Gilbert.
.SH "REPORTING BUGS"
Report bugs to <dgilbert at interlog dot com>.
.SH COPYRIGHT
Copyright \(co 2004\-2021 Douglas Gilbert
.br
This software is distributed under a BSD\-2\-Clause license. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
.SH "SEE ALSO"
.B sg_inq, sg_safte, sg_senddiag, sg_ses_microcode, sg3_utils (sg3_utils);
.B safte\-monitor (Internet)