V1.5 Configuration Limits and Restrictions for IBM FlashSystem 900

Content

Note: This document applies only to the IBM FlashSystem 900, machine type and models 9840-AE2, 9843-AE2 9843-UF3, 9840-AE3, and 9843-AE3. "V1.5" refers to Version 1, Release 5 and applies to firmware releases 1.5.x. To see limits and restrictions for the IBM FlashSystem 840, see V1.2 Configuration Limits and Restrictions for IBM FlashSystem 840. To view the limits and restrictions for the IBM FlashSystem V840, see V1.2 Configuration Limits and Restrictions for IBM FlashSystem V840.

Clustered Systems

The FlashSystem 900 can only cluster two nodes together inside the enclosure. Clustering with any outside enclosure is not supported. There is also no support available for Metro Mirror or Global Mirror replication or split clustering.

Host Limitations

General

While direct host attachment is available, it provides less flexibility than connecting through a switch. Not all host and adapter combinations support direct connect.

Connectivity

An IBM FlashSystem 900, version 1.4.x with MTMs 9840-AE2, 9843-AE2, and 9843-UF3 support the use of Fibre Channel (FC), Fibre Channel over Ethernet (FCoE), Internet Small Computer System Interface (iSCSI), and Infiniband (IB). IBM FlashSystem 900, version 1.5.x with MTMS 9840-AE2, 9843-AE2, 9843-UF3, 9840-AE3, and 9843-AE3 do not support iSCSI or FCoE. At the 1.5 code level and later, FC and IB are supported only.

Refer to IBM System Storage Interoperation Center (SSIC) for more information on interoperability for specific firmware releases within the IBM FlashSystem 900 or other IBM FlashSystem products.

Arbitrated loop (AL) is supported for FC at speeds of 8Gb or slower, while point-to-point (P2P) is supported for FC at any speed. Direct connect requires that FC ports are set to arbitrated loop topology, which only supports 8Gb and slower FC.

FC-AL or P2P can be used to connect to Windows hosts depending on the type of interface card. 8 Gb FC interface cards support both P2P and FC-AL topologies, while 16 Gb interface cards directly attached to the hosts are required to use P2P.

An IBM FlashSystem 900 storage system supports one of the following port configurations:

• 8 ports at 16Gb FC
• 16 ports at 8Gb FC
• 16 ports of 10 Gb FCoE (up to version 1.4.x)
• 16 ports of 10 Gb iSCSI (up to version 1.4.x)
• 8 ports of quad data rate or QDR (40 Gb)

Maximum configurations

Configuration limits for IBM FlashSystem 900:

Property	Maximum Number	Comments
System (Cluster) Properties
Nodes per system	2
I/O groups per system	1
Node Properties
Logins per node Fibre Channel port	512	Only one node is being accessed at a time, therefore the maximum login amount is the same for node and system.
iSCSI sessions per node	256
Volume (Virtual Disk) Properties
Volumes (VDisks) per system		Up to 2048 volumes, depending on the remaining available space.
Volumes per storage pool		No limit is imposed beyond the volumes per system limit.
Fully-allocated volume capacity		Maximum size of a fully-allocated volume is based on RAID 5, where the maximum size of one drive multiplied by 11 equals the full capacity of a fully-allocated volume.
Generic Host Properties
Host objects (IDs) per system	2048
Volume mappings per host object	2048
Total Fibre Channel ports and iSCSI names per host object	512
FC/FCoE/IB Host Properties
Maximum hosts per system	512
Maximum host ports/logins per system	2048
Maximum host ports per host object (ID)	32
Maximum host logins per port	256
iSCSI Host Properties
Maximum hosts per system	N/A	Maximum hosts limited by port limit.
Maximum host ports/logins per system	256
Maximum host ports per host	32
Maximum host logins per port	224
Internal Storage System Properties
Flash module capacity	1.2 TB, 2.9 TB, or 5.7 TB (AE1/AE2) or 10 TB, 20 TB, or 20 TB Large (AE3)	Maximum capacity spans the drives in the array.
Minimum-maximum member drives per RAID-5 array	3-11	Minimum of 3 usable flash member drives and maximum of 11. All RAID-5 arrays are created with the nth drive assigned as the spare.
System and User Management Properties
User accounts per system	400	Includes the default user accounts.
User groups per system	256
Authentication servers per system	1
NTP servers per system	1
iSNS servers per system	1
Concurrent open SSH sessions per system	10
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
SKLM servers per system	4
Remote support assistance per system	12	This includes proxy servers
9840-AE2 / 9843-AE2 Options
Fibre channel cards per node	2	Four interface cards per system with four ports 8Gb or two ports 16Gb FC each.
FCoE per node	2	Four interface cards per system with four ports 10Gb FCoE each.
IB cards per node	2	Four interface cards per system with two ports 40Gb IB each.
iSCSI cards per node	2	Four interface cards per system with four ports 10Gb iSCSI each.
9840-AE3 / 9843-AE3 Options
Fibre channel cards per node	2	Four interface cards per system with four ports 8Gb or two ports 16Gb FC each.
IB cards per node	2	Four interface cards per system with two ports 40Gb IB each.