EMD Storage SecurStor 16i, Installation Manual

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SecurStor16i Installation and Hardware Reference Manual
4-2
WARNING!
All cables must be handled with care. Make sure Ethernet cables do not run parallel
with power cords. To prevent interference within a rack system, the cable routing path
must be carefully planned and they must not be bent.
4.1.2 Network Topologies
The iSCSI host ports connect to Ethernet network devices and iSCSI initiators that
comply with the IETF iSCSI standard (RFC 3720).
Network connection of the EMD SS16i
subsystem’s iSCSI ports is flexible. The use of network connecting devices, subnet, Name
Servers, or iSCSI management software can vary from case to case. In the following sections,
configuration diagrams will be provided to illustrate the possible uses of the EMD SS16i
subsystem in an iSCSI network.
Note that these configurations only recommend but do not intend to impose limitations on the use
of subnet settings or networking paths to servers.
4.1.3 Points of Failure
The primary concern for configuring host-side topologies is that points of failure should be
avoided. It is therefore preferred that the host side be connected to two (2) HBAs and better not the
onboard Ethernet. Data flow and access management should therefore be implemented to avoid
access contention. MPIO software can be implemented in order to discover a capacity volume
through an alternate data link in the event of cabling failure.
4.2 Host Connection Topologies
4.2.1 Sample Topology – Direct-Attached, Dual-path Connection
In the configuration shown in Figure 4-1, one (1) EMD SecurStor16i subsystem is connected to
two (2) servers. These servers are equipped with iSCSI HBAs and using the subsystem as the
shared storage. Multiple arrays or logical partitions can be created and made available separately
through different ID/LUNs on the host ports.
Note the following with the configuration as diagrammed below:
1. The RAIDWatch management software accesses a subsystem through its IP address. A
management station running RAIDWatch can access the array through the 10/100BaseT
management port.
2. Configuration of each port connection into a subnet isolates each iSCSI host link, decreases
overheads, and eliminates the impact of link failure.