Home > Storage > Unity XT > Storage Admin > Dell Unity XT: Introduction to the Platform > I/O Module Options – 380/F, 480/F, 680/F, 880/F
Each Storage Processor on Unity XT systems can support up to two I/O modules. I/O modules provide additional connectivity. For the two Storage Processors in a DPE, the I/O Modules configured must match between SPs. Note that Fibre Channel over Ethernet (FCoE) and Fibre Channel over IP (FCIP) are not supported on the Dell Unity platform.
The Unity XT Series systems support the following I/O modules:
The 12Gb SAS (4-Port) I/O module is used to provide additional backend connectivity to Disk Array Enclosures. Each SAS port supports up to 10 DAEs and up to a maximum of 250 drives. This module is required when utilizing high-bandwidth x8 SAS lane connections for the 80-drive DAE.
The 16Gb Fibre Channel (4-Port) I/O module offers frontend connectivity at 16Gbps speeds and can auto-negotiate to 8Gbps and 4Gbps speeds depending on the SFPs installed. There are ordering options for single-mode SFPs and multi-mode SFPs configurations depending on the use case in a datacenter environment. Single-mode SFPs only operate at 16Gb speeds and are not compatible with multi-mode connections. Single-mode connections are usually used for long distance synchronous replication use cases to remote sites while multi-mode is typically used for transmitting data over shorter distances in local-area SAN networks and connections within buildings. For upgrading a 16Gb Fibre Channel I/O module to a 32Gb Fibre Channel I/O module, see the section I/O Module Conversions for more information.
The 10GbE BaseT (4-Port) I/O module operates at up to 10Gb/s speeds and is used for frontend host access and supports both iSCSI and NAS protocols. The I/O module can also auto-negotiate to 1Gbps and 100Mbps speeds as needed. The ports on an individual Ethernet I/O module, and the on-board Ethernet ports or Mezz card Ethernet ports support link aggregation, fail safe networking (FSN), and VLAN tagging. Link aggregation can be configured across all available Ethernet ports as needed.
The 25GbE Optical I/O module runs at a fixed speed of 25Gbps given it is using 25Gb SFPs. The I/O module also supports 10Gb SFPs to run at 10Gbps speeds. The Optical I/O module ports support SFP+ and TwinAx (active or passive mode) connections. Note that different SFPs and/or TwinAx cables can be mixed on the same I/O module and are hot swappable.
The 32Gb Fibre Channel (4-port) I/O module provides frontend host connectivity for speeds up to 32Gbps with various different SFPs. The 32Gb multi-mode SFP is capable of auto-negotiating to 32Gbps, 16Gbps, and 8Gbps. Meanwhile, the 16Gb multi-mode SFP is capable of auto-negotiating to 16Gbps, 8Gbps, and 4Gbps speeds. A single-mode SFP is also supported which operates only at 16Gbps and is generally used for long distance synchronous replication use cases. The 32Gb I/O module can have different SFP types per port. For example, port 0 could have a 32Gbps SFP while ports 1-3 could have a 16Gbps SFP so long as the SAN supports both speeds. When using multiple SFP types, it is recommended to ensure the peer storage processor has the same SFPs inserted into each port.