Storage system: | ETERNUS DX/AF, Symmetrix/VMAX3 |
Domain: | DEVICE |
Privileges: | TSOS |
/START-SNAP-SESSION
The original units of the snap pairs are specified in the UNIT operand.
A /START-SNAP-SESSION command enables snap units to be generated for all units of a pubset. In this case the pubset is selected using UNIT. In SNAP-UNIT a list of volumes is specified which are not yet being used as snap units and whose number matches the number of units in the pubset.
SHC-OSD checks the global and task-specific security settings before this command is executed (see "Security settings of SHC-OSD"). The current security settings can be displayed with /SHOW-SHC-PROCESSING (see also "SHOW-SHC-PROCESSING Displays settings of SHC-OSD"). They can be changed in the SHC-OSD parameter file (see "Configuration of SHC-OSD") for the next time SHC-OSD is started or with /MODIFY-SHC-PROCESSING for ongoing operations (see "MODIFY-SHC-PROCESSING Changes settings of SHC-OSD").
For SnapOPC+ on ETERNUS DX/AF
The file consistency over multiple volumes must be ensured by the caller. For this purpose a synchronization point should be created for the data before the command is called, see section "Synchronization point for replications".
The server itself can access the snap unit immediately.
The snap pairs are activated immediately. From the application’s viewpoint, the snap unit contains all the data of the original unit at command processing time. On command execution, the snap session assumes the COPY-ON-WRITE status.
The devices for the original unit and snap unit must be contained in the same storage system and be of the same type. The configured size of the snap unit must be greater than or equal to the size of the original unit.
For ETERNUS DX/AF random Thin Devices or Flex Volumes can be used as snap units.
For ETERNUS DX/AF preconfigured snap data volumes (SDV) can be used as snap units.
A maximum of 256 snap units can be configured for an original unit.
The snap pubset on the snap units can be renamed directly using the NEW-PUBSET operand if an SF pubset is involved.
When the data backup with Snapsets is used for pubsets (see the “Introduction to System Administration” manual [5]), SnapOPC+ may not be used for this pubset.
For TimeFinder/Snap on Symmetrix
The server itself cannot access the snap unit.
The snap session assumes the CREATED status on command execution. The snap pair can then be activated using /ACTIVATE-SNAP (see "ACTIVATE-SNAP Activates a snap pair").
The devices for the original unit and the snap unit must be located in the same storage system, and be of the same type and have the same configured size.
Currently a maximum of 127 snap units can be configured for an original unit in the storage system. All these snap sessions together count as one copy session. The maximum value for pubsets can be reduced when data backup with Snapsets (see the “Introduction to System Administration” manual [5]) is used because a specific number of sessions can be reserved for Snapsets.
If snap or clone sessions in the RESTORED status already exist for the original unit, the /START-SNAP-SESSION command is rejected.
For TimeFinder SnapVX on VMAX3
The file consistency over multiple volumes must be ensured by the caller. For this purpose a synchronization point should be created for the data before the command is called, see section "Synchronization point for replications".
The server itself can access the snap unit immediately.
The snap pairs are activated immediately. From the application’s viewpoint, the snap unit contains all the data of the original unit at command processing time. On command execution, the snap session assumes the COPY-ON-WRITE status.
The snapshot is identified by its snapshot name. The snapshot name can be specified explicitly or be created automatically by SHC-OSD.
The devices for the original unit and the snap unit must be located in the same VMAX3, and be of the same type and have the same configured size.
The snap pubset on the snap units can be renamed directly using the NEW-PUBSET operand if an SF pubset is involved.
A maximum of 127 snap units can be configured for an original unit. All these snap sessions together count as one copy session.
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UNIT =
Selects the original units by means of a particular catalog ID (*BY-PUBSET), via the serial number and the internal number of the logical volume in the storage system (*BY-SYMMETRIX/*BY-STORAGE), or directly by means of the mnemonic device name of the logical volume.
UNIT = *BY-PUBSET(...)
Selects units by means of a pubset ID or volume set ID. The pubset is protected against reconfiguration during command processing.
Only relevant for ETERNUS DX/AF and VMAX3: When an SF pubset is selected, the volumes of the snap pubset generated can be renamed directly using NEW-PUBSET.
PUBSET = <cat-id 1..4>
Specifies the pubset ID or volume set ID. When HOLD-IO=*UNTIL-ACTIVATED, no volume set ID may be specified.
NEW-PUBSET =
Only relevant for ETERNUS DX/AF and VMAX3.
Determines the catalog ID of the snap pubsets of the snap units.
NEW-PUBSET = *SAME
The snap pubset is not renamed, i.e. it retains the same name.
NEW-PUBSET = *SPECIAL-VSN
All volumes of the snap units are automatically renamed to prevent confusion with the original. For this purpose the period in a VSN in point notation is changed to a colon (e.g. AA.001 to AA:001), or in PUB notation the PUB string is changed to P:B (e.g. PUBA01 to P:BA01).
NEW-PUBSET = <cat-id 1..4>
An SF pubset’s snap pubset is renamed by specifying the new catalog ID explicitly. The catalog ID can also differ in length from the PUBSET operand. The new snap pubset is also an SF pubset. An existing MRSCAT entry is used if it is of the correct type. If it is not, it is deleted and created again. See the notes in section "Renaming SF pubsets with SHC-OSD".
HOLD-IO =
Only relevant for ETERNUS DX/AF and VMAX3.
Handles inputs/outputs on the snap pair during splitting (see “Consistent splitting of a pubset in the shared pubset network” in "Synchronization point for the snapshot").
HOLD-IO = *NO
The inputs/outputs on the original units are executed without any change. This can lead to data inconsistencies on the snap units for applications which are not suspended before splitting takes place.
HOLD-IO = *UNTIL-ACTIVATED
The inputs/outputs on the original units are suspended until all the imported pubset’s snap pairs are in the COPY-ON-WRITE status. Subsequently inputs/outputs to the units are resumed. If an error occurs when inputs/outputs are suspended or resumed, the command is aborted. The input/output activity may need to be resumed using /RESUME-IO.
UNIT = *BY-SYMMETRIX(...)
Only relevant for Symmetrix/VMAX3.
Selects the unit by means of the serial number of the storage system and the internal number of the logical volume in the storage system.
SERIAL-NUMBER = <alphanum-name 3..12>
Specifies the serial number of the storage system (make sure it is unique!).
LOGICAL-VOLUME = <x-text 1..4>
Specifies the internal number of the logical volume in the storage system
UNIT = *BY-STORAGE(...)
Only relevant for ETERNUS DX/AF.
Selects the unit by means of the internal number of the logical volume in the storage system.
SERIAL-NUMBER = <alphanum-name 3..14>
Specifies the serial number of the storage system (make sure it is unique!).
LOGICAL-VOLUME = <x-text 1..4>
Specifies the internal number of the logical volume in the storage system
UNIT = <alphanum-name 2..2> / <x-text 4..4>
Selects the unit by means of the mnemonic device name of the logical volume.
SNAP-UNIT =
Selects the snap units.
SNAP-UNIT = list-poss(256): <alphanum-name 2..2> / <x-text 4..4>
Specifies the mnemonic device name of the virtual device. A list is accepted only if a pubset was specified in the UNIT operand.
SNAP-UNIT = *BY-SYMMETRIX(...)
Only relevant for Symmetrix/VMAX3.
Selects the snap unit by means of the internal number of the logical volume in the storage system.
SNAP-LOGICAL-VOLUME = <x-text 1..4>
Specifies the internal number of the logical volume in the storage system
SNAP-UNIT = *BY-STORAGE(...)
Only relevant for ETERNUS DX/AF.
Selects the snap unit by means of the internal number of the logical volume in the storage system.
SNAP-LOGICAL-VOLUME = <x-text 1..4>
Specifies the internal number of the logical volume in the storage system
SNAP-UNIT = *AUTO-SELECT
Automatic selection of suitable snap units by SHC-OSD. Snap units are just chosen if they have the exact same configured size as the original unit.
The snap units are selected in accordance with the storage system:
For ETERNUS DX/AF from the set of the existing free and attached BS2000 volumes in special notation, see section “Automatic selection of snap units” in "Freely selectable snap units". After that, if no BS2000 volumes in special notation are available, from the set of the existing free and attached Snap Data Volumes (SDV)
For Symmetrix from the set of the existing free and attached virtual devices
For VMAX3 from the set of the existing free and attached BS2000 volumes in special notation, see section “Automatic selection of snap units” in "Snap units (VMAX3)".
SNAP-UNIT=*AUTO-SELECT is not possible for units which are not generated and not attached.
SNAPSHOT-NAME =
Only relevant for VMAX3.
Specifies the name for the snapshot, see section “Snapshot name” in "Snap units (VMAX3)".
The snapshot is connected with the snap unit specified in SNAP-UNIT=.
SNAPSHOT-NAME = *BY-RULE
The snapshot is given the name generated by SHC-OSD.
SNAPSHOT-NAME = <posix-filename_1..32>
The snapshot is given the specified name. Use of case sensitivity and uniqueness within the VMAX3 must be ensured.
SAVE-POOL =
Only relevant for Symmetrix.
Selects the save pool for the virtual devices to be assigned.
SAVE-POOL = *BY-PRESELECTION
The save pool which was selected using the SHC-OSD parameter file or the /MODIFY-SHC-PROCESSING command is used.
SAVE-POOL = *DEFAULT-POOL
The storage system’s default pool is used as the save pool.
SAVE-POOL = <name 1..32 with-under with-low>
Specifies the name of the save pool.
This specification is case-sensitive.
SELECT =
Defines whether the unit specified in the UNIT operand or (when remote replication is used) the target unit of a remote copy pair is selected as the original unit of the snap pair.
SELECT = *STD
Selects the unit which was defined in the UNIT operand.
SELECT = *TARGET-UNIT(...)
Selects the target unit of a remote copy pair as the original unit. The relevant source unit is specified in the UNIT operand.
RA-GROUP =
Only relevant for Symmetrix/VMAX3.
Selects the target unit using the RA group in the case of concurrent target units.
RA-GROUP = *UNIQUE
Selects the one existing target unit.
RA-GROUP = <integer 1..250>
Specifies the RA group for selecting the target unit.
Command processing
Message NDE1073 is output to SYSOUT for each device and distributed via routing code 0, i.e. it is logged in the CONSLOG file only. You will find detailed information on the CONSLOG file (log file) in the “Introduction to System Administration” manual [5].
Examples
/START-SNAP-SESSION UNIT=5000,SNAP-UNIT=5040
/START-SNAP-SESSION UNIT=5001,SNAP-UNIT=*AUTO-SELECT
/START-SNAP-SESSION UNIT=*BY-PUBSET(PUBSET=TFS),SNAP-UNIT=(5100,5101,5102)
(Pubset TFS consists of 3 units)
/START-SNAP-SESSION UNIT=*BY-PUBSET(PUBSET=A,NEW-PUBSET=C),
SELECT=*TARGET-UNIT
(see "SnapOPC+ and REC (ETERNUS DX/AF)")
Command return codes
(SC2) | SC1 | Maincode | Meaning |
0 | CMD0001 | Command executed successfully | |
1 | 0 | NDE2003 | Command successfully executed, no processing necessary |
2 | 0 | NDE2004 | Command successfully executed but not yet completed |
1 | CMD0202 | Syntax error | |
32 | NDE2002 | Internal error | |
64 | CMD0087 | Function not permitted in the current input mode or with the current task privileges | |
64 | CMD0216 | Required privilege not available | |
64 | NDE1000 | Device not found or not in the storage system | |
64 | NDE1001 | Device not attached | |
64 | NDE1003 | Data medium not online or not unique | |
64 | NDE1004 | Pubset not found or wrong pubset type | |
64 | NDE1008 | Volume cannot be allocated | |
64 | NDE1010 | Enginuity version is not supported (too low) | |
64 | NDE1015 | Device not defined in BS2000 | |
64 | NDE1043 | Pubset type not supported | |
64 | NDE1044 |
| |
64 | NDE1052 | Maximum number of TimeFinder mirrors exceeded | |
64 | NDE1055 | Function not supported for Symmetrix/VMAX3 storage systems | |
64 | NDE1058 | All free snap units reserved for snapset | |
64 | NDE1100 | Invalid pubset state | |
64 | NDE1101 | More than one sharer for pubset | |
64 | NDE1102 | Not all volumes could be allocated | |
64 | NDE1103 | No reconfiguration lock for pubset | |
64 | NDE1105 | Inconsistent pubset | |
64 | NDE1108 |
| |
64 | NDE1109 |
| |
64 | NDE1110 |
| |
64 | NDE1114 | Serial number not found | |
64 | NDE1115 | Serial number not unique | |
64 | NDE1116 | Storage system’s logical volume not found | |
64 | NDE1140 | Duplicate MN in MN list | |
64 | NDE1142 | Mirror pair already exists | |
64 | NDE1150 | No gatekeeper device found | |
64 | NDE1153 | Symmetrix device lock set | |
64 | NDE1154 | Disk belongs to a meta-disk | |
64 | NDE1171 | Target unit is not unique | |
64 | NDE1172 | RA group invalid for the specified unit | |
64 | NDE1410 | No or too few free and matching Snap units | |
64 | NDE1411 | Save pool does not support device type of Snap pair | |
64 | NDE1412 | Requested save pool does not exist | |
64 | NDE1430 | No Snap function for device | |
64 | NDE1431 | Different number of devices for units and snap units | |
64 | NDE1434 | Virtual snap unit already used in other pair | |
64 | NDE1435 | Device is a virtual unit | |
64 | NDE1437 | MNs of the unit and of the snap unit are identical | |
64 | NDE1438 | Unit and virtual snap unit are different types | |
64 | NDE1439 | Unit and virtual snap unit on different storage systems | |
64 | NDE1440 | Incorrect state of unit (of a snap pair) | |
64 | NDE1441 | Incorrect state of snap unit | |
64 | NDE1458 | Unit and Snap unit meta volumes of different stripe size | |
64 | NDE1470 | Type of SNAP-UNIT must not be mixed (SDV and Thin) | |
64 | NDE1535 | Device is a clone unit | |
64 | NDE1702 | Connection to SYMAPI server aborted | |
64 | NDE1800 | Device not found or not in storage system | |
64 | NDE1810 | Storage system’s operating system version not supported | |
64 | NDE1812 | StorMan server switched off by command | |
64 | NDE1814 | Storage system’s serial number not found | |
64 | NDE1815 | Storage system’s serial number not unique | |
64 | NDE1816 | Storage system’s logical volume not found | |
64 | NDE1820 | Reconstruction in storage system not yet completed | |
64 | NDE1833 | No suitable Storman server found | |
64 | NDE1840 | Unit and Snap unit on different storage systems | |
64 | NDE1850 | All mirror disks of the unit reserved for snapset use | |
64 | NDE1852 | Maximum number of local mirrors exceeded | |
64 | NDE1853 | Storage unit locked | |
64 | NDE1870 | Snap pair created | |
64 | NDE1872 | Automatic attachment of snap unit(s) failed | |
64 | NDE1880 | Copy license not installed (ETERNUS DX/AF) | |
64 | NDE1881 | Copy Table Size not configured (ETERNUS DX/AF) | |
64 | NDE1882 | Copy Table Size too small (ETERNUS DX/AF) | |
64 | NDE1883 | Advanced Copy operations for devices locked (ETERNUS DX/AF) | |
64 | NDE2000 | Execution partially successful | |
64 | NDE2001 | Command not executed | |
64 | NDE2009 | Command aborted with K2 key | |
64 | NDE2011 | Symmetrix license not entered | |
64 | NDE2013 | SYMAPI error in command | |
64 | NDE2014 | StorMan error in command | |
64 | NDE2018 | Error on SYMAPI server during the current editing | |
130 | NDE1082 | Memory bottleneck during processing of command | |
130 | NDE2005 | Command cannot be executed at the moment | |