V7.5 Configuration Limits and Restrictions for IBM Storwize V3500

Content

The use of WAN optimization devices such as Riverbed is not supported in native Ethernet IP partnership configurations containing Storwize V3500.


Fabric Limitations
Only one FCF ( Fibre Channel Forwarder ) switch per fabric is supported.


Host Limitations

Microsoft Offload Data Transfer ( ODX ) and SDDDSM Requirements

Storwize V3500 version 7.5.0 introduced support for Microsft ODX. In order to utilise this function all windows hosts accessing Storwize V3500 are required to be at a minimum SDDDSM version of 2.4.5.0. Earlier versions of SDDDSM are not supported when the ODX function is activated.


Windows NTP server

The Linux NTP client used by Storwize V3500 may not always function correctly with Windows W32Time NTP Server


Windows SAN Boot Clusters (MSCS):

It is possible to SAN boot a Microsoft Cluster subject to the following restrictions imposed by Microsoft:

• On Windows 2003, clustered disks and boot disks can be presented on the same storage bus, but ONLY if the Storport driver is being used.

These restrictions and more are described in the Microsoft White Paper: "Microsoft Windows Clustering: Storage Area Networks".

IBM have not tested, and therefore do not support, modifying the registry key as suggested on page 28 (which would allow boot disks and clustered disks on the same storage bus on Windows 2003 without the Storport driver).


TPC Restrictions

TPC Supported Versions
The minimum supported TPC version for SVC/Storwize version 7.5 is TPC 5.2.6.

Vdisk Migration
When a vdisk is migrated between a child pool and its parent, or between child pools of the same parent, it is necessary to re-probe the cluster from TPC as no event is logged on the cluster for this type of migration

Migrations between non-child pools also currently require a re-probe

These issues will be addressed in future releases of TPC and SVC/Storwize Code.


Oracle

Oracle Version and OS	Restrictions that apply:
Oracle RAC 10g on Linux Host:	1

Restriction 1: For RHEL4 set Oracle Clusterware 'misscount' parameter to a bigger one to allow SDD to do path failover first. The default miscount setting 60s is too short for SDD. We recommend to set it 90s or 120s. Command to use: crsctl set css misscount 90


Priority Flow Control for iSCSI

Priority Flow Control for iSCSI is supported on Brocade VDX 10-gigabit Ethernet switches only.


SCSI LUN ID 0
SAS Hosts running Linux or Vmware operating systems.

Removal of LUN's mapped to SCSI ID 0 is not supported and may result in a loss of access to the remaining LUNs.



Maximum Configurations

Configuration limits for Storwize V3500:

Maximum WWPNs per host Object and iSCSI Names

The maximum number of FC/SAS/FCoE hosts ports supported per host object is now 32 (previously 512).
The maximum number of iSCSI names supported per host object is now 8 (previously 256).

Please see the following document

http://www-01.ibm.com/support/docview.wss?uid=ssg1S1005261

Property	Maximum Number	Comments
System (Cluster) Properties
Control enclosures per system (cluster)	1	Each control enclosure contains two node canisters
Nodes per system	2	Arranged as one I/O group
Nodes per fabric	64	Maximum number of maximum number of SVC or Storwize family system nodes that can be present on the same Fibre Channel fabric, with visibility of each other
Fabrics per system	4	The number of counterpart Fibre Channel SANs which are supported - Up to 4 fabrics using the Fibre Channel HIC
USB ports	2
Node Properties
Logins per node Fibre Channel port	512	Includes logins from server HBAs, disk controller ports, node ports within the same system and node ports from remote systems
iSCSI sessions per node	256	512 in IP failover mode (when partner node is unavailable)
Managed Disk Properties
Managed disks (MDisks) per system	4096	The maximum number of logical units which can be managed by a system This number also includes external MDisks which are in use as image mode migration candidates
Managed disks per storage pool (managed disk group)	128
Storage pools per system	1024
Parent pools per system	128
Child pools per system	1023
Managed disk extent size	8192 MB
Capacity for an individual internal managed disk (array)	1 PB	No limit is imposed beyond the maximum number of drives per array limits. Maximum size is dependent on the extent size of the Storage Pool. Comparison Table: Maximum Volume, MDisk and System capacity for each extent size.
Capacity for an individual external managed disk	1 PB	External managed disks may only be used for image mode migration purposes Comparison Table: Maximum Volume, MDisk and System capacity for each extent size.
Total storage capacity manageable per system	32 PB	Maximum requires an extent size of 8192 MB to be used This limit represents the per system maximum of 2^22 extents. Comparison Table: Maximum Volume, MDisk and System capacity for each extent size.
Volume (Virtual Disk) Properties
Volumes per system	2048
Thin-provisioned (space-efficient) volume copies per system	2048	No limit is imposed here beyond the volume copies per system limit.
Volumes per storage pool	-	No limit is imposed beyond the volumes per system limit
Fully-allocated volume capacity	256 TB	Maximum size for an individual fully-allocated volume. Maximum size is dependent on the extent size of the Storage Pool. Comparison Table: Maximum Volume, MDisk and System capacity for each extent size.
Thin-provisioned (space-efficient) volume capacity	256 TB	Maximum size for an individual thin-provisioned volume. Maximum size is dependent on the extent size of the Storage Pool. Comparison Table: Maximum Volume, MDisk and System capacity for each extent size.
Host mappings per system	20,000	See also - volume mappings per host object below
Mirrored Volume (Virtual Disk) Properties
Copies per volume	2
Volume copies per system	2048
Total mirrored volume capacity per I/O group	256 TB
Generic Host Properties
Host objects (IDs) per system	256	A host object may contain both Fibre Channel ports and iSCSI names
Host objects (IDs) per I/O group	256	Refer to the additional Fibre Channel and iSCSI host limits below
Volume mappings per host object	512
Total Fibre Channel ports and iSCSI names per system	2048
Total Fibre Channel ports and iSCSI names per host object	32
iSCSI names per host object (ID)	8
Fibre Channel Host Properties
Fibre Channel hosts per system	256	Requires the Fibre Channel HIC
Fibre Channel host ports per system	512	Requires the Fibre Channel HIC
Fibre Channel hosts ports per host object (ID)	32	Requires the Fibre Channel HIC
iSCSI Host Properties
iSCSI hosts per system	256
iSCSI names per host object (ID)	8
Copy Services Properties
FlashCopy mappings per system	4096
FlashCopy targets per source	256
FlashCopy mappings per consistency group	512
FlashCopy consistency groups per system	255
Internal Storage Properties
Drives per system	24
Min-Max drives per enclosure	0-12 or 0-24	Limit depends on the enclosure model
Simultaneous autosparing	Drives per system
RAID Properties
RAID arrays per system	128	Limit depends on the number of drives in the system
Min-Max member drives per RAID-0 array	1-8
Min-Max member drives per RAID-1 array	2-2
Min-Max member drives per RAID-5 array	3-16
Min-Max member drives per RAID-6 array	5-16
Min-Max member drives per RAID-10 array	2-16
Hot spare drives	-	No limit is imposed
System and User Management Properties
User accounts per system	400	Includes the default user accounts
User groups per system	256	Includes the default user groups
Authentication servers per system	1
NTP servers per system	1
iSNS servers per system	1
Concurrent open SSH sessions per system	32
Event Notification Properties
SNMP servers per system	6
Syslog servers per system	6
Email (SMTP) servers per system	6	Email servers are used in turn until the email is successfully sent
Email users (recipients) per system	12
LDAP servers per system	6

Extents

The following table compares the maximum volume, mdisk and system capacity for each extent size.

Extent size (MB)	Maximum non thin-provisioned volume capacity in GB	Maximum thin-provisioned volume capacity in GB	Maximum MDisk capacity in GB	Total storage capacity manageable per system*
16	2048 (2 TB)	2000	2048 (2 TB)	64 TB
32	4096 (4 TB)	4000	4096 (4 TB)	128 TB
64	8192 (8 TB)	8000	8192 (8 TB)	256 TB
128	16,384 (16 TB)	16,000	16,384 (16 TB)	512 TB
256	32,768 (32 TB)	32,000	32,768 (32 TB)	1 PB
512	65,536 (64 TB)	65,000	65,536 (64 TB)	2 PB
1024	131,072 (128 TB)	130,000	131,072 (128 TB)	4 PB
2048	262,144 (256 TB)	260,000	262,144 (256 TB)	8 PB
4096	262,144 (256 TB)	262,144	524,288 (512 TB)	16 PB
8192	262,144 (256 TB)	262,144	1,048,576 (1024 TB)	32 PB

* The total capacity values assumes that all of the storage pools in the system use the same extent size.