MMS Disk Archiving [PSARC/2008/621 FastTrack timeout 10/10/2008]

Dean Roehrich Dean.Roehrich at sun.com
Fri Oct 3 12:45:22 PDT 2008


I am submitting this case on behalf of David Major.  It is set to timeout on
October 10th, 2008.

The new mmsadm.1 manpage and manpage diffs are in the case directory.

Dean

-------------

Template Version: @(#)onepager.txt 1.35 07/11/07 SMI
Copyright 2007 Sun Microsystems

1. Introduction
   1.1. Project/Component Working Name:
	MMS (Media Management System) Disk Archiving

   1.2. Name of Document Author/Supplier:
	David Major

   1.3. Date of This Document:
	09/22/08
	
	1.3.1. Date this project was conceived:
		08/14/08

   1.4. Name of Major Document Customer(s)/Consumer(s):
	1.4.1. The PAC or CPT you expect to review your project:
		Solaris PAC

	1.4.2. The ARC(s) you expect to review your project:
		PSARC

	1.4.3. The Director/VP who is "Sponsoring" this project:
		Karen.Jourdenais at Sun.COM

	1.4.4. The name of your business unit:
		Archive Software BU353

   1.5. Email Aliases:
    	1.5.1. Responsible Manager: Gregory.Matthews at Sun.COM
    	1.5.2. Responsible Engineer: David.Major at Sun.COM
    	1.5.3. Marketing Manager: Margaret.Hamburger at Sun.COM 
	1.5.4. Interest List: smms-developer at sun.com

2. Project Summary
   2.1. Project Description:
	MMS (Media Management System) Disk Archiving Improvements

   2.2. Risks and Assumptions:
	Existing disk archiving configurations and data will not be
	valid. The only user of disk archiving is ADM (PSARC/2007/210
	Automatic Data Migration).  The MMS and ADM products have not
	yet shipped in a release of Solaris.

3. Business Summary
   3.1. Problem Area:
	Disk archiving media must be usable by hosts with different
	architectures and directory structures.

   3.2. Market/Requester:
	Sun

   3.3. Business Justification:
	Provide customers with disk archiving configuration options.

   3.4. Competitive Analysis:
	Most backup applications provide disk as a storage option.

   3.5. Opportunity Window/Exposure:
	Work should be completed before Nevada RR.

   3.6. How will you know when you are done?:
	When MMS QA can use the same disk archiving media on hosts
	with different library directory structures.

	When MMS QA can export and import a ZFS filesystem
	containing disk archiving media between x64 and sparc.

4. Technical Description:
    4.1. Details:

	I. DDA (Driver for Disk Archiving) File Data

	The disk archiving DDA file data will be stored in big endian to
	support x64 and sparc media. Media written by big-endian hosts
	are unaffected by the change and can continue to use existing
	media.

	II. DDA Performance

	The disk archiving DDA index file record will be cached in memory
	until a change in block size, tape motion or filemark occurs then
	the record is written to disk.

	III. Disk Archiving Configuration Changes

	Current implementation:
	1. Current implementation of DISK cartridges allows one path for
	   each DISK cartridge. This works for MMS that runs on only one host. 
	   In a multi hosts  environment, DMs on different hosts have to access 
	   the same cartridge using the same path. In some cases this is not 
	   possible because the file system on which a DISK cartridge resides 
	   may have different mountpoint names.
   
	2. Using the current implementation in a distributed environment, MM 
	   does not know which DM and LM have access to a DISK cartridge. This
	   makes it impossible for MM to mount DISK cartridges.

	New implementation:
	1. A DISK library emulates a SCSI attached library with multiple ports
	   attached to different hosts.

	   To access a SCSI attached library, an LM must be able to open a
	   path to the library. Once the library is opened, all cartridges
	   and drives in the library are accessible from the host.

	   If a SCSI attached library is attached to different hosts, the paths 
	   with which LMs and DMs use to open the library in each host may be 
	   different.

	   A particular path which may be used in some of the hosts
	   to access a library may be designated as the default path. A host
	   that is unable to use the default path has to have a host specific
	   path.

	   This means that a LM of a SCSI attached library has to run on a 
	   host that can access the library.

	   To emulate this, a DISK library is a directory in a filesystem
	   mounted on a host and the path of the DISK library will be the
	   path used by a DISK LM and DM to access the library. DISK cartridges
	   in the library are subdirectories in the DISK library. A DISK
	   cartridges must have the same name as the CartridgePCL. Once LM/DM
	   opens a DISK library, its cartridges will be also accessible.

	   If a DISK library is accessible from multiple hosts, a path will be
	   designated as the default path. Host specific paths may be
	   specified by a LIBRARYACCESS object, which has attributes that holds
	   the hostname and the path.

	   DISK cartridges accessible by the same set of hosts should
	   be put into the same DISK library.

	   A DISK LM for a DISK library must run on one of the hosts that can
	   access the library.

	2. Keep and use the data model specified in the IEEE MMS standard.

	   Add DefaultLibraryPath to LIBRARY object.
		LIBRARY
		DefaultLibraryPath	A default path which can be used by 
					hosts without a LIBRARYACCESS

	   DefaultLibraryPath must be specified when a DISK LM is created.

	   A new object is needed to hold a host specific path of a library.

	   The new object is LIBRARYACCESS which has attributes that holds
	   the hostname and the path.

		LIBRARYACCESS	Specify the path with wich a host can
				access the library.
		LibraryName	Name of library
		HostName	Hostname
		LibraryPath	Path to access the library.

    
    
      CARTRIDGE                               LIBRARY
    +--------------------+             +----------------------+
    | LibraryName:       |------------>| LibraryName:         |
    |   mylib            |      |----->|   mylib              |
    |--------------------|      |      |----------------------|
    | CartridgePCL:      |      |      | DefaultLibraryPath:  | Default path for
    |   000000           |      |      |   /x/y/mylib         | hosts without
    |--------------------|      |      |----------------------| a LIBRARYACCESS
    | CartridgeShapeName:|      |      | LibraryType:         |
    |   DISK             |      |      |   DISK               |
    +--------------------+      |      +----------------------+
                                |
                                |
                                |        LIBRARYACCESS
                                |      +------------------+
                                |------| LibraryName:     |
                                |      |   mylib          |
                                |      |------------------|
                                |      | HostName:        |
                                |      |   HostA          |
                                |      |------------------|
                                |      | LibraryPath:     |      Path for HostA
                                |      |   /a/b/mylib     |
                                |      +------------------+
                                |
                                |
                                |        LIBRARYACCESS
                                |      +------------------+
                                |------| LibraryName:     |
                                       |   mylib          |
                                       |------------------|
                                       | HostName:        |
                                       |   HostB          |
                                       |------------------|
                                       | LibraryPath:     |      Path for HostB
                                       |   /p/q/mylib     |
                                       +------------------+
    

	3. A DISK LM of a DISK library must run on one of the hosts which has
	access to the library.

	Operations:
	1. When a DISK LM starts, it will open the DISK library and configure
	   cartridges in the library.

	2. DISK DMs will handle all mounts and unmounts of DISK cartridges.

	3. MM will handle DISK cartridges the same way it handles real
	   cartridges.

	Changes:
	1. mmsadm will be changed to require the admin to specify a default
	   library path when a DISK library is created.

	2. mmsadm will be changed to not accept the cartridge path when a 
	   cartridge is created.

	3. mmsadm will be changed to accept request to create host specific
	   library paths and create LIBRARYACCESS objects.

	4. MM will be changed to handle DefaultLibraryPath and host specific
	   path.

	5. To open LMs and DMs, LM and DM will be changed to look for a host
	   specific path to use first and if none exists for the host, the 
	   DefaultLibraryPath will be used.


    4.2. Bug/RFE Number(s):

	CR 6726606 RFE:  Support new disk archiving library, drive and volume
	configuration

	CR 6726606 Unable to mount disk volume that was created on opposite
	platform

	CR 6612080 dda performance 
    
    4.3. In Scope:
	None

    4.4. Out of Scope:
	None
    
    4.5. Interfaces:

	Addition of public object to IEEE 1244-1 data model for disk archiving
	configuration.

	Change public mmsadm(1M) disk archiving configuration CLI.

	Change private DDA (driver for disk archiving) media format on x64 to
	big endian.
 
    4.6. Doc Impact:

	mmsadm(1M) man page

    4.7. Admin/Config Impact:

	Minor change in the way a user specifies disk archiving library
	and media configuration.  The mmsadm(1M) command will not support
	dkvol and dkdrive but will instead support the library dkpath and
	dkaltpath. The library dkpath is the DefaultLibraryPath and
	the optional dkaltpath is the LibraryPath on a host by host bases. 

    4.8. HA Impact:

	none
    
    4.9. I18N/L10N Impact:

	none
    
    4.10. Packaging & Delivery:

	none
    
    4.11. Security Impact:

	none	
    
    4.12. Dependencies:

	CR 6703197 MM isn't checking database to see if it needs to be upgraded or downgraded

5. Reference Documents:

	PSARC/2007/420 - MMS
	CR 6691475 Integrate Media Management System (MMS)
	IEEE std 1244-1 Media Management System

6. Resources and Schedule:
   6.1. Projected Availability:

	Q2FY09

   6.2. Cost of Effort:

	3 engineers for one month
	1 QA
	1 Pub

   6.3. Cost of Capital Resources:
	Already available

   6.4. Product Approval Committee requested information:
   	6.4.1. Consolidation or Component Name: onnv
	6.4.3. Type of CPT Review and Approval expected: FastTrack
        6.4.4. Project Boundary Conditions: 
		// Give the document's URL  http://....
	6.4.5. Is this a necessary project for OEM agreements: No
	6.4.6. Notes: None
	6.4.7. Target RTI Date/Release: onnv build 103, November 2008
	6.4.8. Target Code Design Review Date: November 2008
	6.4.9. Update approval addition: None

   6.5. ARC review type:
		FastTrack
   6.6. ARC Exposure:
		open
       6.6.1. Rationale:
		Enhancement to existing onnv software component.

7. Prototype Availability:
   7.1. Prototype Availability:
	n/a

   7.2. Prototype Cost:
	n/a



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