flash_archive(4)
NAME
flash_archive - format of flash archive
SYNOPSIS
flash_archive
DESCRIPTION
A flash archive is an easily transportable version of a
reference configuration of the Solaris operating environ-
ment, plus optional other software. Such an archive is used
for the rapid installation of Solaris on large numbers of
machines. The machine that contains a flash archive is
referred to as a master system. A machine that receives a
copy of a flash archive is called a clone system.
There are two types of flash archives: full and differen-
tial. A full archive is used for initial installation or
whenever a complete, fresh installation is called for. A
differential archive is used to update an installation. A
full archive contains all of the files from a master and
overwrites the installed software on a clone completely. A
differential archive contains only the differences between
the software on a master and on a clone. These differences
include new files, changed files, and deleted files. (These
will be deleted on clones, as well). Installation of a dif-
ferential archive is faster and consumes fewer resources
than installation of a full archive.
You create a flash archive, full or differential, with the
flar(1M) or flarcreate(1M) command. You view information
about a given flash archive with flar. flar also enables you
to split or combine the sections of a flash archive.
Flash archives are monolithic files containing both archive
identification information and the actual files that have
been copied from a master system and that will be extracted
onto a clone system. The standard extension for a flash
archive is .flar.
The flash archive is laid out in the following sections:
o archive cookie
o archive identification
o manifest (for differential archives only)
o predeployment
o postdeployment
o reboot
o summary
o user-defined (optional)
o archive files
The only assumptions regarding section number and placement
that an application processing the archive can make is that
there is an identification section located immediately after
the archive cookie and that the last section in the archive
is an archive files section.
These sections are described in the following subsections.
Archive Cookie
The very beginning of the archive contains a cookie, which
serves to identify the file as a flash archive. It is also
used by the deployment code for identification and valida-
tion purposes.
The case-sensitive, newline-terminated cookie that identi-
fies version 1.n flash archives, is FlAsH-aRcHiVe-1.n, where
n is an integer in the range 0 through 9.
The archive version is designed to allow for the future evo-
lution of the flash archive specification while allowing
applications that process flash archives to determine
whether specific archives are of a format that can be han-
dled correctly. The archive version is a number of the form
x.y, where x is the major version number, and y is the minor
version number.
When an application encounters a flash archive with an
unknown major version number, it should issue an error mes-
sage and exit.
Archive Identification Section
The archive identification section is plain text, delimited
with newline characters. It is composed of a series of
keyword/value pairs, with one pair allowed per line. Key-
words and values are separated by a single equal sign. There
are no limits to the length of individual lines. Binary data
to be included as the value to a keyword is base64 encoded.
The keywords themselves are case-insensitive. The case-
sensitivity of the values is determined by the definition of
the keyword, though most are case-insensitive.
The global order of the keywords within the identification
section is undefined, save for the section boundary key-
words. The identification section must begin with
section_begin=ident and must end with section_end=ident.
In addition to the keywords defined for the flash archive
and enumerated below, users can define their own. These
user-defined keywords are ignored by the flash mechanisms,
but can be used by user-provided scripts or programs that
process the identification section. User-defined keywords
must begin with X, and contain characters other than
linefeeds, equal signs, and null characters. For example,
X-department is a valid user-defined keyword. department,
which lacks the X- prefix, is not. Suggested naming conven-
tions for user-defined keyword include the underscore-
delimited descriptive method used for the pre-defined key-
words, or a federated convention similar to that used to
name Java packages.
Applications that process the identification section will
process unrecognized non-user-defined keywords differently,
depending on whether the archive version is known. If the
application recognizes the archive specification version, it
will reject any unrecognized non-user-defined keyword. If
the application does not recognize the specification ver-
sion, that is, if the minor version number is higher than
the highest minor version it knows how to process, unrecog-
nized non-user-defined keywords will be ignored. These
ignored keyword are reported to the user by means of a non-
fatal warning message.
The keywords defined for this version of the Flash archive
specification are listed below.
Keyword Value Required
section_begin text yes
section_end text yes
archive_id text no
files_archived_method text no
files_compressed_method text no
files_archived_size numeric no
files_unarchived_size numeric no
creation_date text no
creation_master text no
content_name text yes
content_type text no
content_description text no
content_author text no
content_architectures text list no
creation_node text no
creation_hardware_class text no
creation_platform text no
creation_processor text no
creation_release text no
creation_os_name text no
creation_os_version text no
Future versions of the identification section might define
additional keywords. The only guarantee regarding the new
keywords is that they will not intrude upon the user-defined
keyword namespace as given above.
The following is an example identification section:
section_begin=identification
files_archived_method=cpio
files_compressed_method=compress
files_archived_size=259323342
files_unarchived_size=591238111
creation_date=20000131221409
creation_master=pumbaa
content_name=Finance Print Server
content_type=server
content_description=Solaris 8 Print Server
content_author=Mighty Matt
content_architectures=sun4u
creation_node=pumbaa
creation_hardware_class=sun4u
creation_platform=SUNW,Sun-Fire
creation_processor=sparc
creation_release=5.9
creation_os_name=SunOS
creation_os_version=s81_49
x-department=Internal Finance
section_end=identification
The following are descriptions of the identification section
keywords:
o section_begin
o section_end
These keywords are used to delimit sections in the archive
and are not limited exclusively to the identification sec-
tion. For example, the archive files section includes a
section_begin keyword, though with a different value. User-
defined archive sections will be delimited by section_begin
and section_end keywords, with values appropriate to each
section. The currently defined section names are given in
the table below. User-defined names should follow the same
convention as user-defined identification sections, with the
additional restriction that they not contain forward slashes
( / ).
Section Boundary
identification identification
archive files archive
archive cookie cookie
Note that while the archive cookie does not use section
boundaries, and thus has no need for a section name within
the archive itself, the flar(1M) command uses section names
when splitting the archive, and thus requires a section name
for the archive cookie. The name cookie is reserved for that
purpose.
The following keywords, used in the archive identification
section, describe the contents of the archive files section.
archive_id
This optional keyword uniquely describes the contents
of the archive. It is computed as a unique hash value
of the bytes representing the archive. Currently this
value is represented as an ASCII hexadecimal 128-bit
MD5 hash of the archive contents. This value is used
by the installation software only to validate the con-
tents of the archive during archive installation.
If the keyword is present, the hash value is recom-
puted during extraction based on the contents of the
archive being extracted. If the recomputed value does
not match the stored value in the identification sec-
tion, the archive is deemed corrupt, and appropriate
actions can be taken by the application.
If the keyword is not present, no integrity check is
performed.
files_archived_method
This keyword describes the archive method used in the
files section. If this keyword is not present, the
files section is assumed to be in CPIO format with
ASCII headers (the -c option to cpio). If the keyword
is present, it can have the following value:
cpio The archive format in the files section is CPIO
with ASCII headers.
The compression method indicated by the
files_compressed_method keyword (if present) is applied to
the archive file created by the archive method.
The introduction of additional archive methods will
require a change in the major archive specification
version number, as applications aware only of cpio
will be unable to extract archives that use other
archive methods.
files_compressed_method
This keyword describes the compression algorithm (if
any) used on the files section. If this keyword is not
present, the files section is assumed to be
uncompressed. If the keyword is present, it can have
one of the following values:
none The files section is not compressed.
compress
The files section is compressed using
compress(1).
The compression method indicated by this keyword is applied
to the archive file created by the archive method indicated
by the value of the files_archived_method keyword (if any).
gzip compression of the flash archive is not currently sup-
ported, as the gzip decompression program is not included in
the standard miniroot.
Introduction of an additional compression algorithm
would require a change in the major archive specifica-
tion version number, as applications aware only of the
above methods will be unable to extract archives that
use other compression algorithms.
files_archived_size
The value associated with this keyword is the size of
the archived files section, in bytes. This value is
used by the deployment software only to give extrac-
tion progress information to the user. While the
deployment software can easily determine the size of
the archived files section prior to extraction, it
cannot do so in the case of archive retrieval via a
stream. To determine the compressed size when extract-
ing from a stream, the extraction software would have
to read the stream twice. This double read would
result in an unacceptable performance penalty compared
to the value of the information gathered.
If the keyword is present, the value is used only for
the provision of status information. Because this key-
word is only advisory, deployment software must be
able to handle extraction of archives for which the
actual file section size does not match the size given
in files_archive_size.
If files_archive_size is not present and the archive
is being read from a stream device that does not allow
the prior determination of size information, such as a
tape drive, completion status information will not be
generated. If the keyword is not present and the
archive is being read from a random-access device such
as a mounted file system, or from a stream that pro-
vides size information, the compressed size will be
generated dynamically and used for the provision of
status information.
files_unarchived_size
This keyword defines the cumulative size in bytes of
the extracted archive. The value is used for file sys-
tem size verification. The following verification
methods are possible using this approach:
No checking
If the files_unarchived_size keyword is absent,
no space checking will be performed.
Aggregate checking
If the files_unarchived_size keyword is present
and the associated value is an integer, the
integer will be compared against the aggregate
free space created by the requested file system
configuration.
The following keywords provide descriptive information about
the archive as a whole. They are generally used to assist
the user in archive selection and to aid in archive manage-
ment. These keywords are all optional and are used by the
deployment programs only to assist the user in distinguish-
ing between individual archives.
creation_date
The value of the creation_date keyword is a textual
timestamp representing the time of creation for the
archive. The value of this keyword can be overridden
at archive creation time through the flarcreate(1M).
The timestamp must be in ISO-8601 complete basic
calendar format without the time designator (ISO-8601,
f5.4.1(a)) as follows:
CCYYMMDDhhmmss
For example:
20000131221409
(January 31st, 2000 10:14:09pm)
The date and time included in the value should be in
GMT.
creation_master
The value of the creation_master keyword is the name
of the master machine used to create the archive. The
value can be overridden at archive creation time.
content_name
The value of the content_name keyword should describe
the archive's function and purpose. It is similar to
the NAME parameter found in Solaris packages.
The value of the content_name keyword is used by the
deployment utilities to identify the archive and can
be presented to the user during the archive selection
process and/or the extraction process. The value must
be no longer than 256 characters.
content_type
The value of this keyword specifies a category for the
archive. This category is defined by the user and is
used by deployment software for display purposes. This
keyword is the flash analog of the Solaris packaging
CATEGORY keyword.
content_description
The value of this keyword is used to provide the user
with a description of what the archive contains and
should build on the description provided in
content_name. In this respect, content_description is
analogous to the DESC keyword used in Solaris pack-
ages.
There is no length limit to the value of
content_description. To facilitate display, the value
can contain escaped newline characters. As in C, the
escaped newline takes the form of 0. Due to the
escaped newline, backlashes must be included as \.
The description is displayed in a non-proportional
font, with at least 40 characters available per line.
Lines too long for display are wrapped.
content_author
The value of this keyword is a user-defined string
identifying the creator of the archive. Suggested
values include the full name of the creator, the
creator's email address, or both.
content_architectures
The value of this keyword is a comma-delimited list of
the kernel architectures supported by the given
archive. The value of this keyword is generated at
archive creation time, and can be overridden by the
user at that time. If this keyword is present in the
archive, the extraction mechanism validates the kernel
architecture of the clone system with the list of
architectures supported by the archive. The extraction
fails if the kernel architecture of the clone is not
supported by the archive. If the keyword is not
present, no architecture validation is performed.
The keywords listed belowhave values filled in by uname(2)
at the time the flash archive is created. If you create a
flash archive in which the root directory is not /, the
flash archive software inserts the string UNKNOWN for all of
the creation_* keywords except creation_node,
creation_release, and creation_os_name. For creation_node,
the flash software uses the contents of the nodename(4)
file. For creation_release and creation_os_name, the flash
software attempts to use the contents of
<root_directory>/var/sadm/system/admin/INST_RELEASE. If it
is unsuccessful in reading this file, it assigns the value
UNKNOWN.
Regardless of their sources, you cannot override the values
of the creation_* keywords.
creation_node
The return from uname -n.
creation_hardware_class
The return from uname -m.
creation_platform
The return from uname -i.
creation_processor
The return from uname -p.
creation_release
The return from uname -r.
creation_os_name
The return from uname -s.
creation_os_version
The return from uname -v.
Manifest Section
The manifest section is used only for differential flash
archives. It contains a filter that specifies selection of
an operating environment image and a list of the files to be
retained in, added to, and deleted from a clone system. The
list contains permissions, modification times, and other
information on each file. The flash software uses this sec-
tion to perform a consistency check prior to deployment of
an archive on a clone. If the user who created the
differential archive used the -M option to flar(1M) or
flarcreate(1M), this section will not be present.
The manifest section is for the exclusive use of the flash
software. The format of this section is internal to Sun and
is subject to change.
Predeployment, Postdeployment, and Reboot Sections
Contain internal information that the flash software uses
before and after deploying an operating environment image.
These sections are for the exclusive use of the flash
software.
Summary Section
Contains a summary of archive creation. This section records
the activities of predeployment and postdeployment scripts.
User-Defined Sections
Following the identification section can be zero or more
user-defined sections. These sections are not processed by
the archive extraction code and can be used for any purpose.
User-defined sections must be line-oriented, terminated with
newline (ASCII 0x0a) characters. There is no limit on the
length of individual lines. If binary data is to be included
in a user-defined section, it should be encoded using base64
or a similar algorithm.
Archive Files Section
The archive files section contains the files gathered from
the master system. While the length of this section should
be the same as the value of the files_archived_size keyword
in the identification section, you should not assume that
these two values are equal. This section begins with
section_begin=archive, but it does not have an ending sec-
tion boundary.
ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:
____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|_____________________________|
| Availability | SUNWinst |
|_____________________________|_____________________________|
SEE ALSO
compress(1), cpio(1), flar(1M), flarcreate(1M), md5(3EXT),
attributes(5)
Man(1) output converted with
man2html