Release Notes

System configuration
8 Dell EMC SC Series: Performance and Availability | 4024-BP-SC
1.6 Front-end connectivity
SC Series storage provides multiple options for front-end connectivity with on-board ports directly on the
controller and optional host bus adapters (HBAs). This section discusses recommendations for the different
types of connectivity.
In general, front-end ports need to be connected and configured symmetrically across the both controllers to
facilitate high availability and continued connectivity in case of a controller failure.
For best performance, it is recommended to use all front-end ports that are installed in the system so that the
workload is spread across as many resources as possible.
1.6.1 Fibre Channel
When configured for Fibre Channel, 8Gb and 16Gb HBAs are available for all platforms. The SC5020,
SC7020, and SC9000 also support 32Gb Fibre Channel HBAs. All Fibre Channel ports can negotiate to lower
speeds. Dell EMC recommends single-initiator zoning when creating zone sets (using a single server port per
zone). For more information on switch configurations, refer to Switch configuration guides for SC Series and
PS Series SANs.
1.6.2 iSCSI
SC Series storage supports iSCSI connections on multiple 1Gb/s and 10Gb/s port options. 10GBase-T ports
can auto-negotiate to 1Gb/s speeds. 10Gb/s is recommended for the best performance. Use separate
networks and VLANs to segregate iSCSI traffic from normal network traffic. If possible, configure Jumbo
frames (MTU 9000) on all ports in the end-to-end network to provide the best performance.
Other suggested iSCSI recommendations include the following:
• Bi-directional flow control enabled on all server and switch ports that handle iSCSI
• Unicast storm control disabled on switches handling iSCSI
• Multicast and broadcast disabled at the switch for any iSCSI VLANs
• Multicast storm control and broadcast storm control enabled when multicast and broadcast cannot be
disabled
• Routing disabled between regular network and iSCSI network.
• Not using spanning tree on ports connected directly to end nodes
• Ensuring switches used for iSCSI are of a non-blocking design
• ARP Redirect enabled using QLogic
®
SANsurfer
®
for boot from SAN
• ARP Redirect enabled within ESX with hardware iSCSI HBAs to assist in controller failover
• Using 10Gb SFP+ optical or copper, BASE-T, iSCSI DCB, IPv6, or 1Gb Base-T ports
1.7 SAS front end
The SC5020, SC3020, SC4020, and SCv2020 models have the option to directly connect to servers with SAS
HBAs through 12Gb SAS. SAS front-end connectivity options are limited to switchless fabrics; Dell EMC does
not support SAS switches at this time. Dell EMC recommends that only validated servers and SAS HBAs be
used in these configurations. For more information on validated servers and SAS HBAs, see the Dell EMC
Storage Compatibility Matrix.