Sun Microsystems StorEdge 3000 Series, Installation, Operation And Service Manual

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Chapter 5 First-Time Configuration 5-11
Note – When in loop mode and connected to a Fabric switch , each host ID is
displayed as a loop device on the switch so that, if all 16 IDs are active on a
given channel, the array looks like a loop with 16 nodes attached to a single
switch FL port.
In public loop mode, the array can have a maximum of 1024 LUNs, where 512
LUNs are dual-mapped across two channels, primary and secondary controller
respectively.
5.4.2 A SAN Point-to-Point Configuration Example
A point-to-point configuration has the following characteristics:
■
In SAN configurations, the switches communicate with the Sun StorEdge 3510 FC
Array host ports using a Fabric point-to-point (F_port) mode.
■
When you use Fabric point-to-point (F_port) connections between a Sun StorEdge
3510 FC Array and Fabric switches, the maximum number of LUNs is limited to
128 LUNs for a nonredundant configuration and is limited to 64 LUNs for a
redundant configuration.
■
Fibre Channel standards allow only one ID per port when operating point-to-
point protocols, resulting in a maximum of four IDs with a maximum of 32 LUNs
for each ID, resulting in a combined maximum of 128 LUNs.
■
The working maximum number of LUNs is actually 64 LUNs in a configuration
where you configure each LUN on two different channels for redundancy and to
avoid a single point of failure.
In a dual-controller array, one controller automatically takes over all operation of a
second failed controller in all circumstances. However, when an I/O controller
module needs to be replaced and a cable to an I/O port is removed, the I/O path is
broken unless multipathing software has established a separate path from the host to
the operational controller. Supporting hot-swap servicing of a failed controller
requires the use of multipathing software, such as Sun StorEdge Traffic Manager
software, on the connected servers.
Note – Multipathing for the Sun StorEdge 3510 FC Array is provided by Sun
StorEdge Traffic Manager software. Refer to Sun StorEdge 3510 FC Array Release Notes
for information about which versions of Sun StorEdge Traffic Manager software are
supported on which platforms.