docu42125 snapcli for vnx oe for block release notes version 05.32.000.5.006

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EMC® SnapCLI for VNX™ OE for Block

Version 05.32.000.5.006

Release Notes P/N 300-014-098

REV 01 July 16, 2012

These release notes contain supplemental information about EMC VNX Snapshots SnapCLI software for EMC VNX series storage systems.

Please read these release notes completely before installing or using the software.

Topics include:

Revision history ..........................................................................................2 Product description ....................................................................................2 New features and changes .........................................................................3 Environment and system requirements ..................................................3 Fixed problems ............................................................................................4 Known problems and limitations .............................................................4 Technical notes ............................................................................................7 Documentation .......................................................................................... 17 Software media, organization, and files ................................................ 18 Installation ................................................................................................. 18 Troubleshooting and getting help .......................................................... 19

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Revision history

SnapCLI for VNX OE for Block Version 05.32.000.5.006 Release Notes

Revision history

The following table presents the revision history of this document.

Revision Date Description 01 July 16, 2012 Initial release

Product description

VNX Snapshot

EMC® VNX™ Snapshots is a storage system-based software application that allows you to create a copy of a LUN by using mapping technology. You can use the VNX Snapshot for data backups, decision support, data modeling, or software application testing. It can also be used as a base for temporary operations on the production data without damaging the original data on the primary LUN.

A snapshot takes only seconds to create. Depending on your application needs, you can create VNX Snapshot, and snapshots of VNX Snapshot.

SnapCLI

The SnapCLI program runs on host systems in conjunction with VNX Snapshot running on the VNX series storage processors (SPs). It lets you create, copy, attach, detach, and destroy VNX Snapshots. All SnapCLI commands are sent to the storage system through the front end ports using Fibre Channel bus, iSCSI, or FCoE.

The SnapCLI utility is an executable program that is run interactively or with a script.

For all Microsoft Windows and UNIX platforms, flush the cached data from the production host before you create VNX Snapshot. Also, flush the cached data on the secondary if you modified the VNX Snapshot. Failure to do so may result in an inconsistent or unusable point-in-time copy.

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New features and changes

S SnapCLI for VNX OE for Block Version 05.32.000.5.006 Release Notes

New features and changes

There are no new features in this release.

Environment and system requirements

Table 1 lists the hardware and software supported by the SnapCLI software.

Table 1: Environment and system requirements

Environment System requirements Hardware VNX series systems only

Operating system • HP-UX 11.0 and 11i or later • IBM AIX 5.1 or later • Linux 2.4 and 2.6 Kernels (32-bit and 64-bit) • Solaris • Windows Server 2003 and Windows Server 2008 (32-bit and

64-bit)

Storage system software VNX OE version 05.32.000.5.006 or later for VNX series storage systems. In addition, the Block enabler and the VNX Snapshots enabler must be installed.

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Fixed problems


Fixed problems

There are no new fixed problems in this release.

Visit the EMC Online Support website at http://Support.EMC.com for the most recent updates and information about the SnapCLI software.

Known problems and limitations

This section identifies outstanding issues in this version along with known solutions or workarounds.

Platforms Symptom details Problem description Solution or workaround

All supported platforms

A snapcli command may report a failure but the command succeeds if the target LUN is trespassed during the operation. (286532) Frequency of occurrence: Rarely under a specific set of circumstances Severity: Low

The snapcli command may report a failure but the operation succeeds if the target LUN of the operation is trespassed during the SnapCLI operation.

The actual state of the operation can be verified using Unisphere® software. Exists in versions: 05.32.000.5.006

AIX The snapcli attach command executed in an AIX PowerPath® environment may generate SC_DISK_ERR2 messages in the system log file. (215474) Frequency of occurrence: Likely under a specific set of circumstances Severity: Low

The error messages are generated due to a detached VNX snapshot mount point being present in the storage group. Whenever VNX snapshot mount points are in the storage group, running cfgmgr will cause ASC 2051 problems in the errpt file. The messages are harmless and can be ignored.

Activate the VNX snapshot mount point using Navisphere Secure CLI and then you can execute SnapCLI on the host to prevent these messages from being generated. Exists in versions: 05.32.000.5.006

Linux VNX snapshots are SnapCLI cannot access The Linux kernel creates

https://support.emc.com/�

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not attached on a Linux system if more than eight device paths are required to complete the operation. (286533) Frequency of occurrence: Always under a specific set of circumstances Severity: Medium

more than eight device paths on the backup host.

only eight SG devices (SCSI generic devices) by default. Additional SG devices must be created and then linked to the SD devices. (The internal disk uses one of the SG devices). Use the Linux utility /dev/MAKEDEV to create additional SCSI generic devices. Exists in versions: 05.32.000.5.006

Windows SnapCLI fails when the operation is targeted for a dynamic disk. (286529) Frequency of occurrence: Always Severity: Low

VNX Snapshot containing a dynamic disk, which is rolled back to the production host, cannot be imported on the production host using SnapCLI.

Dynamic disks must be imported using the Disk Administrator or the Microsoft Diskpart utility. Exists in versions: 05.32.000.5.006

Windows

The snapcli create command fails if the volume contains a Veritas volume and the LUNs for that volume are trespassed to the secondary path. (206345) Frequency of occurrence: Always Severity: Low

The snapcli create command fails with Error: 0x3E050011 (One or more devices need manual attention by the operator), if the volume contains a Veritas volume and the LUNs for that volume are trespassed to the secondary path.

Trespass the volume to the primary path or use Navisphere Secure CLI to create the VNX Snapshot. Exists in versions: 05.32.000.5.006

Windows The snapcli attach command may return a warning if the operating system maintains a drive letter mapping for the volume being brought online.

The snapcli attach command generates a warning that one or more devices are not assigned drive letters, when the other volumes are assigned drive letters.

This usually occurs when the registry contains stale device mapping information. Update the registry by using a utility from Microsoft called “scrubber” to remove stale entries. The stale

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(225937) Frequency of occurrence: Always under a specific set of circumstances. Severity: Low

device mapping information generates a condition that prevents SnapCLI from determining if all volumes attached were assigned drive letters. SnapCLI generates a warning. Exists in versions: 05.32.000.5.006

Windows SnapCLI fails to create or destroy a VNX Snapshot in a DMP environment. (226043) Frequency of occurrence: Always under a specific set of circumstances. Severity: Low

SnapCLI fails to create or destroy a VNX Snapshot in a DMP environment.

The failure is due to the trespassing of the LUN that is the target of the SnapCLI operation. The DMP/Volume Manager keeps track of the current storage processor owner independently from the operating system. To resolve this issue, trespass the volume to the peer storage processor and reissue the snapcli command. Exists in versions: 05.32.000.5.006

Windows The snapcli list command may list devices multiple times when executed in a DMP environment. (225832) Frequency of occurrence: Always under a specific set of circumstances. Severity: Low

The snapcli list command may list devices multiple times when executed in a DMP environment.

Use the –d option on the command line to suppress duplicate entries for a particular device or volume. Exists in versions: 05.32.000.5.006

Solaris The snapcli attach command causes LUNs to trespass on the host in a DMP environment. (207655)

The snapcli attach command (when issued without the –o <device> parameters) scans the SCSI bus using the primary and secondary paths for the devices,

Use the –o <device> option for the snapcli attach command. Exists in versions: 05.32.000.5.006

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Technical notes



Frequency of occurrence: Always. Severity: Low

causing the LUNs to trespass.

SuSE

If “rpm” is used on SuSE systems during the installation or removal process, either warning messages are generated or there are problems in installing or uninstalling SnapCLI. (230902) Frequency of occurrence: Always under a specific set of circumstances. Severity: Low

The package fails to complete the operation (installation or removal) or warning messages are generated.

Use the yast2 command on SuSE Linux systems to install or remove the SnapCLI package. Exists in versions: 05.32.000.5.006

Technical notes

This section contains technical information for SnapCLI.

Generic notes (apply to all platforms)

VNX Snapshots

If VNX Snapshots mount points are created using Navisphere Secure CLI, use the -allowInbandSnapAttach yes option to attach VNX Snapshots to them using SnapCLI.

VNX Snapshot created with SnapCLI always has -allowReadWrite property set to no, to prevent accidental modifications to the Snapshot. The -f option forces SnapCLI to attach the snapshot, regardless of the current value of snapshot's -allowReadWrite property.

The -f option does not modify the value of the -allowReadWrite property, which can only be changed using EMC Unisphere.

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Technical notes


SnapCLI

SnapCLI must be used with VNX OE for Block 05.32.000.5.006 or later software. If the VNX is not running a compatible revision of software, the snapCLI command will fail with an error message.

This applies to the following attaches:

HP-UX 11.0 and 11i or later

IBM AIX 5.1 or later

Linux 2.4 and 2.6 Kernels (32-bit and 64-bit) Solaris

Windows Server 2003 and Windows Server 2008 (32-bit and 64-bit)

SnapCLI platform-specific notes

AIX

SnapCLI recognizes file systems on logical volumes for create and destroy operations. SnapCLI includes an online man page.

HP-UX

See Veritas VxVM (HP-UX, Linux, and Solaris) for details about support to Veritas Volume Manager.

SnapCLI recognizes the agile view devices as a valid object type, in addition to legacy view devices.

SnapCLI support for legacy and agile view is concurrent. Therefore, you can specify devices names using legacy view, agile view, or a combination of both. For example:

#snapcli create -s s1 -o /dev/rdsk/c1t0d0,/dev/rdisk/disk27 –c cg1

Note: If the legacy mode is disabled on the HP-UX host, you can specify device names only using agile view.

SnapCLI supports HP-UX PowerPath.

When the –o option is not present in the SnapCLI attach command line, SnapCLI rescans the SCSI bus for new devices, by default, before attaching the VNX Snapshot mount point. On IA64 systems (HP-UX 11.23), the rescan operation may take several minutes to complete. This delay can be avoided by adding the –r 0 option to the command line, if the VNX Snapshot mount points are already accessible by the host, as this is not the initial time the devices are being discovered by the host software. If the –o option is specified on the command line, then the SCSI

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Technical notes


bus is not rescanned, by default. Therefore, the –r 0 option is not necessary.

SnapCLI recognizes file systems on logical volumes for create and destroy operations. SnapCLI includes an online man page.

Linux (iSCSI) Linux has added support for the iSCSI file system mount table to supplement /etc/fstab. The Linux iSCSI software uses the entries in the /etc/fstab.iscsi file to mount devices after the iSCSI module is loaded. Use iscsi-mountall to mount those devices. The file was created because the iSCSI module is not loaded when the system is booted. Therefore, no iSCSI devices are accessible when the mount command is run and all entries are processed. The iSCSI devices are available until the iSCSI protocol stack is started. If the iSCSI-based devices or file systems are configured in the /etc/fstab file, they fail to be mounted when the system is booted and can possibly hang the system.

SnapCLI processes entries that are configured in the /etc/fstab only.

The solution to this is to configure the iSCSI devices in the /etc/fstab with the automount option set to false or 0. This option prevents those file systems from being accessed when the system is booted and the /etc/fstab is processed.

Once the system is initialized and the iSCSI protocol stack is available, the iscs-mountall can be executed and the devices or file systems mounted.

Linux

SnapCLI recognizes Linux MPIO’s mpath devices as a valid object type. For example:

#snapcli create –s s1 –o /dev/mapper/mpath37

SnapCLI does not recognize any other Linux MPIO naming convention, including /dev/dm-* devices.

SnapCLI support to Linux MPIO and PowerPath is orthogonal, which means that only one of these failover packages can be installed on a host at a time.


The SnapCLI package includes an online man page.

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Technical notes


Solaris


SnapCLI recognizes disks labeled using EFI Disk Label as a valid object type, in addition to disks labeled using SMI Disk Label.

SnapCLI includes an online man page.

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Technical notes


Veritas VxVM (HP-UX, Linux, and Solaris)

SnapCLI supports creating or destroying VNX Snapshot on simple Veritas volumes by specifying the volume name. For example, you can create VNX Snapshot on the whole Veritas volume v01 by specifying:

snapcli create –s mysession –o v01 –c mycg

Snapcli issues create or destroy operation to all devices that compose that volume.

Snapcli supports creating or destroying VNX Snapshot on file systems mounted on top of Veritas volumes; for example:

snapcli create –s s1 –o /target –c cg1

where /target is the mount point for a file system created on top of a Veritas volume.

The operations that are not supported in snapCLI, but may be added in a future version, are as follows:

Creating a VNX Snapshot on Veritas plexes. Creating a VNX Snapshot on Veritas subdisks. Creating a VNX Snapshot on Veritas sub-volumes. Creating a VNX Snapshot on ANY other Veritas virtual

object. Enclosure-based naming scheme. SnapCLI recognizes Veritas volumes created on disks named using the enclosure-based naming scheme (as opposed to the disk-based naming scheme) for create and destroy operations. For example:

# vxdisk list DEVICE TYPE DISK GROUP STATUS Disk_0 auto:none - - online invalid Disk_1 auto - - error Disk_2 auto:simple dg0101 dg01 online Disk_3 auto - - error Disk_4 auto:simple dg0102 dg01 online

# vxassist -g dg01 make v01 1500m

# snapCLI create -s s1 -o v01 –c cg1

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Technical notes


Veritas DMP (multiple platforms)

If you install and use the DMP software for Solaris, HP-UX, or Linux, you must use persistent VNX Snapshots. DMP-installed systems will sometimes generate I/O requests to both SPs for a LUN. For EMC VNX Snapshots, this will cause a snapshot to trespass when the non-owning SP receives the I/O request. A persistent snapshot will survive the trespass operation and I/O will continue normally. Non-persistent snapshots will terminate. Also, for SnapCLI operations that use the –o <pathname> parameter, you can use the Solaris example /dev/vx/rdmp/cXtXdXsX pathnames as arguments.

Windows Server 2003 and Windows Server 2008

Silent mode installation: SnapCLI supports silent mode installation.

Snapcli with Windows Server 2003, Windows Server 2008: SnapCLI and VNX Snapshots support configurations where the VNX Snapshots mount point device is added to the storage group that contains the primary LUN. This allows you to access the VNX Snapshots on the same host as the primary LUN.

Snapcli and nested mount points: SnapCLI does not support nested mount points. You can use the physical device name as arguments to create and destroy operations.

Snapcli and nested mount points: A backup host reboot is required to properly dismount the stale Disk Volume mount point if the VNX Snapshot is destroyed without detaching it first using SnapCLI.

Terminal Services/Remote Desktop: On Windows hosts, if Terminal Services/Remote Desktop is installed, SnapCLI operations will succeed, but you may not see the drive letter assignment. To view the drive letter assigned, log out and log back in into the server. To avoid this issue, do not use Terminal Services/Remote Desktop on attached hosts. Snapcli detach and manual deletion of drive letters: On the backup host, if the drive letter is deleted before issuing the snapcli detach command, the Windows host will be unable to flush the file system buffers to the LUN on the storage system. As a result, you will see old data on subsequent VNX Snapshots that are attached. To avoid this issue, do not delete the drive letters of the LUNs that you use for VNX Snapshots. Snapcli “list” on Windows platforms: Using snapcli list and specifying the WWN on a multi-partitioned LUN will list only one of the drive letters. Using the –d <drive letter> option on the command line allows you to successfully list the other partition on the LUN.

Snapcli on multi-partitioned LUNs: When using SnapCLI and VNX Snapshots on multi-partitioned LUNs you must properly select the

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Technical notes


snapshot to be attached on the second host. For example, if you create two distinct snapshots on the two partitions of a multi-partitioned LUN, a single attach will allow you to access both LUN partitions since VNX Snapshots operates at the LUN level – but the two partitions accessed with one VNX Snapshots mount point are from one snapshot. You can access four partitions, two from the first snapshot attached on the multi-partitioned LUN and two from the second snapshot.

Snapcli attach with Windows Server 2003 and Windows Server 2008: The snapcli attach command does not allow the use of drive letters A:, B:, C:, or D: for command line arguments specified with the –d option. These drive letters are the default for the system devices and the snapCLI attach command is designed not to allow the use of these volume letters. If you specify one of these drive letters for an attach command, snapCLI attaches the snapshot and reports the physical drive on which the LUN is present, but will not assign a drive letter as you requested for A:, B:, C:, or D: and that drive letter cannot be assigned.

Snapcli detach: The snapcli detach command does not delete the drive letter if the volume is in use by services or applications on the host. SnapCLI requires exclusive access on the drive letter to detach the snapshot. For example, if Windows Explorer is open and the drive letter or volume that will be deleted is being accessed, snapCLI will not delete the drive letter and will inform the user that an application is using the drive letter. Snapcli detach of drive letters in use by Veritas: The snapcli detach command fails if the drive letter contains a Veritas volume. This is due to the Veritas software keeping the volume open, preventing the snapcli detach command from gaining exclusive access to the volume for removal. The volume must be exported first; then the snapcli detach command can be executed. Dynamic Disks – Detach: To detach VNX Snapshots that is composed of Dynamic Disks, use Computer Management to delete the volumes that compose the activated snapshot. Then execute:

snapcli detach –s snapshot_name

SnapCLI will report a message such as:

Detached snapshot_name on \\.\physicaldevice1, physicaldevice2 ... ..

Indicating that the snapshot is detached.

SnapCLI and Admsnap

Admsnap is a command line utility, offering functionality similar to SnapCLI. Admsnap has previously been distributed with SnapView, while SnapCLI is being distributed with VNX Snapshots.

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Technical notes


Tables below provide a comparison of how or where you can use each of these products in their environment.

Concept Description SnapCLI Admsnap Array Application Application on the EMC

disk array that processes the commands issued by the specified inband CLI.

VNX Snapshots SnapView

Enablers Special packages required on the array to enable the array application functionality.

• UnisphereBlock

• VNXSnapshots

• UnisphereBlock

• SnapView

Point-in-time copy Point in time copy of a specified LUN.

VNX Snapshot SnapView session

Supported LUN types The type of the LUNs being used as the source of the Point-in-time copy.

• Thick LUN • Thin LUN

• Thick LUN

• Thin KUN

• FLU

Private LUNs Additional disk space required to accomplish the Point-in-time copy.

Not needed Reserved LUN Pool Note: You have to allocate Reserved LUN pool before you start any SnapView Session.

Mount point LUN Point-in-time copy’s mount point.

VNX Snapshot mount point

SnapView Snapshot

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Technical notes


Operation Description SnapCLI Admsnap Create a mount point LUN

Creates a mount point LUN to be associated with a point-in-time copy.

naviseccli –h IPAddress lun –create –type Snap –primaryLun primaryLunNumber –l lunNumber –allowInbandSnapAttach yes Note: You can create a Mount point LUN before or even after you create a VNX Snapshot. Be sure to use the -allowInbandSnapAttach yes option, if you want to attach VNX Snapshots to the Mount point, using SnapCLI.

naviseccli –h IPAddress snapview –createsnapshot target_lun_number -snapshotname name Note: You have to create a Mount point LUN before you start any SnapView session.

Create a point-in-time copy

Creates a point-in-time copy of a specified LUN.

snapCLI create -s snap_name -o object_name. Note: A VNX Snapshot created with snapCLI always has allowReadWrite property set to No, in order to prevent accidental modifications to the Snapshot. If object_name is constituted of multiple LUNs, you have to specify a consistent point-in-time copy, even if you didn’t when you used to use admsnap

admsnap start -s session_name -o object_name

Consistent point-in-time copy

A point-in-time copy that maintains host IO dependencies within an IO stream that spans a set of one or more primary LUNs.

snapCLI create -s snap_name -o object_name[,object_name] -c cg_name Note: A VNX Snapshot created with snapCLI always has allowReadWrite property set to No, in

admsnap start - -s session_name -o object_name[,object_name] -c

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Technical notes


Operation Description SnapCLI Admsnap order to prevent accidental modifications to the copy of the Snapshot.

Copy a point-in-time copy

Creates a copy of a point-in-time copy.

snapcli copy -s snap_name -b snap_name -o object_name Note: A VNX Snapshot copied with snapCLI always has allowReadWrite property set to No, in order to prevent accidental modifications to the copy of the Snapshot.

Not available

Attach a point-in-time copy

Brings a point-in-time copy online, by associating it to a mount point LUN, making it available for host I/O. Note: In the case of snapCLI, this includes copies of a point-in-time copy.

snapcli attach -s snap_name -f Note: The -f option forces snapCLI to attach the Snapshot, regardless of the current value of the Snapshot's allowReadWrite property. The -f option does not modify the value of the allowReadWrite property, which can only be changed via EMC Unisphere Changes made to an attached VNX Snapshot™ are permanent, even if it’s detached.

admsnap activate -s session_name Note: Changes made to a SnapView Sessions are discarded once it’s deactivated.

Detach a point-in/time copy

Removes the association of a point-in-time copy with a mount point LUN. Host access to the point-in-time copy is removed.

snapclidetach -s snap_name Note: Any writes made to the point-in-time copy are permanent even after it‘s detached.

admsnap deactivate -s session_name Note: Any writes made to the point-in-time copy are discarded.

Destroy a point-in-time copy

Destroys a point-in-time copy

snapcli destroy -s snap_name -o

admsnap stop -s session_name -o

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Documentation


Operation Description SnapCLI Admsnap Note: In the case of snapCLI, this includes copies of a point-in-time copy.

object_name object_name

Flush Flushes host buffers. snapcli flush admsnap flush List Lists available VNX

and CX™ series devices.

snapcli list admsnap list

Documentation

Table 2 lists the documents that apply to SnapCLI.

Table 2: Available documentation Part number Name

300-014-125 VNX for Block Concepts 300-013-428 EMC VNX Command Line Interface (CLI) Reference for Block

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Software media, organization, and files


Software media, organization, and files

Table 3 lists the applicable software for this product version.

Table 3: SnapCLI software

Product Location Description

SnapCLI http://Support.EMC.com • snapCLI-AIX-32--en_US-3.32.0.0.3-1.lpp • snapCLI-HPUX-32--en_US-3.32.0.0.4-1.dep • snapCLI-Linux-32-x86-en_US-3.32.0.0.3-1.rpm • snapCLI-Linux-64-x86-en_US-3.32.0.0.3-1.rpm • SNAPCLI-Solaris-32-sparc-en_US-3.32.0.0.3-

1.pkg • SNAPCLI-Solaris-32-x64-en_US-3.32.0.0.3-1.pkg • snapCLI-Win2K3-32--en_US-3.32.0.0.3-1.exe • snapCLI-Win2K8-32--en_US-3.32.0.0.3-1.exe

Installation

Install SnapCLI on a Windows host, by executing the SnapCLI InstallShield package on your software media.

Install SnapCLI on any other supported operating systems, using the native package management system available on that operating system, and the appropriate SnapCLI package on your software media.


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Troubleshooting and getting help



This section provides specific instructions for contacting EMC Customer Service and obtaining additional information about EMC products.

Where to get help

EMC support, product, and licensing information can be obtained as follows:

Product information

For documentation, release notes, software updates, or for information about EMC products, licensing, and service, go to the EMC Online Support website (registration required) at: http://Support.EMC.com.

Troubleshooting

Go to the EMC Online Support website. After logging in, locate the appropriate Support by Product page.

Technical support

For technical support and service requests, go to EMC Customer Service on the EMC Online Support website. After logging in, locate the appropriate Support by Product page and choose either Live Chat or Create a service request. To open a service request through EMC Online Support, you must have a valid support agreement. Contact your EMC Sales Representative for details about obtaining a valid support agreement or to answer any questions about your account.

Note: Do not request a specific support representative unless one has been assigned to your particular system problem.


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docu42125 snapcli for vnx oe for block release notes version 05.32.000.5.006

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