Sun Microsystems StorEdge N8600 Filer, Руководство по модернизации

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4 Sun StorEdge N8600 Filer Storage Upgrade Guide • September 2001
Upgrading a Sun StorEdge N8600 Filer
The Sun StorEdge N8600 Filer is composed of one rack with a Sun Enterprise™ 4500
server and up to two partner groups of Sun StorEdge T3 arrays, plus one or two
additional racks containing up to four partner groups each.
Redundancy is built into the filer at all levels. A partner group continues to function
with the loss of a power supply, a controller board, or a Fibre Channel arbitrated-
loop (FC-AL) host bus adapter. The rack that contains the partner groups has two
power distribution systems that back each other up in case of failure, and the two
FC-AL hubs are fully redundant. There is no single-point-of-failure (SPOF) in the
entire data path of a rack of partner groups.
In addition to the redundancy of the rack’s hardware, each array power supply has
a built in battery backup system. If main power is lost, the battery provides enough
power for the array to shut itself down properly.
The server hardware is also redundant and includes three I/O modules each of
which contains two FC-AL host bus adapters, which connect to the partner group’s
FC-AL hubs. The failure of any host bus adapter or I/O module poses no threat to
availability because the FC-AL hubs are connected in such a way that no rack is
connected to only one I/O module. See
FIGURE 3
for one possible wiring scheme.
The only requirement to maintain redundancy at the I/O modules is to have each of
the two lines from the partner group’s FC-AL hubs connect to different I/O
modules. For instance, in
FIGURE 3
, the FC-AL hubs of rack #1 are connected to I/O
modules #1 and #3; the FC-AL hubs of rack #2 are connected to
I/O modules #1 and #2; and the FC-AL hubs of rack #3 are connected to I/O
modules #2 and #3. No rack has both of its data lines connected to a single I/O
module, providing an alternate data path if any I/O module fails. Again, there is no
SPOF.
In upgrading the storage capacity of your filer, you might have to install another
rack for the new partner groups. Once the partner groups are installed and
connected according to the instructions in this guide, connect the two Fibre Channel
connections from the new rack’s FC-AL hubs to the I/O modules of the server. There
will be two connections available at the server on different I/O modules to maintain
redundancy.