The shared storage design uses Internet Small Computer Systems Interface (iSCSI) for single-system and multisystem management solutions. The solutions have the following iSCSI characteristics:
- Dell Unity XT with 10BASE-T connectivity accesses block storage using iSCSI. The Cisco Nexus 93108TC-FX3P management switch provides connectivity that is based on 10BASE-T on each SP and is connected to the management switch ports.
- Dell Unity XT with optical connectivity storage accesses block storage using iSCSI. The Cisco Nexus 92348GC-X management switch provides connectivity that is based on optical 25 GbE ports, using the mezzanine adapter on each SP that is connected to the management switch uplink ports.
The connectivity to the management switches is:
- SPA even ports - switch A
- SPA odd ports - switch B
- SPB even ports - switch B
- SPB odd ports - switch A
The iSCSI network design is based on the following Dell and VMware best practices:
- VMware vSphere ESXi setting for Delayed Ack is disabled.
- iSCSI is Layer 2.
- Switch ports are set to access mode.
- Jumbo frames are enabled.
- Unity XT with 10BASE-T connectivity uses the following IP address subnet range assignments:
- /28 subnets within the iSCSI VLAN for data traffic between Dell Unity XT and VMware vSphere ESXi hosts.
- One subnet for up to two servers for single system and multisystem management.
- Round-robin assignments for servers across Unity XT front-end storage ports.
- Two iSCSI VMkernel ports on each host per subnet and one per NIC uplink.
- Up to two hosts may connect to a pair of iSCSI array ports for single system and multisystem management. For example, hosts 1 and 11 map to the SPA ETH 2 and SPB ETH2 pair.
- Unity XT with 25 GbE optical connectivity uses the following IP address subnet range assignments:
- /28 subnets within the iSCSI VLAN for data traffic between Unity XT and VMware vSphere ESXi.
- One subnet for up to three servers for single-system and multisystem management.
- Round-robin assignments for servers across Unity XT front-end storage ports.
- Two iSCSI VMkernel ports on each host per subnet and one per NIC uplink.
Up to three hosts can connect to a pair of iSCSI array ports for single-system and multisystem management. For example, hosts 1, 3, and 5 map to the SPA mezzanine port 2 and SPB mezzanine port 2 pair.