How the combination of
convergence and high-density
affect racks and cabling
The current trend towards moving storage into the server
housing is resulting in network consolidation. As a result,
cabling density is increasing at the server housing and at the
switch or router – which needs to be reflected in infrastructure
design.
Ever since major providers of IT infrastructures launched
the principle of Software-Defined Storage (SDS), previous
storage systems have been on the decline. When X86 servers
with PCIe 3.0 bus appeared on the market about four years
ago, the conditions were created for the integration of storage
tasks into the server infrastructure. Suddenly, a standard
server on two height units with six card slots offered more
bandwidth and performance potential than any midrange
storage system. This integrated concept has several powerful
economic advantages.
Powerful servers are a necessity in today’s data centres,
which need to run numerous virtual machines. By investing in
additional server disks, storage volume can be easily added.
For example, on the basis of SDS, servers for virtual machines
are equipped with 24 rather than only two or three disks.
These evolutionary advances, however, haven’t resulted
in a reduction in the amount of cabling in data centres – this
merely shifted and could even increase. When planning Data
Centre infrastructure, this has to be taken into account. Until
now, cables would run from the server’s network interface
card to the Ethernet switch as well as from the server’s host
bus adapter to the fibre channel switch and from there to
the storage. The number of cables was split over the relevant
areas, which meant cabling density was still relatively low.
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virtualisation means data traffic between servers grows. At
the same time, there’s a further increase in CPU and PCI
performance. These advances should also get through to
users – they expect acceptable latency.
Improvements in quality can only be achieved with more
bandwidth and higher performance from the cabling. The
evolution of data centre networks described can only be
successfully implemented with more bandwidth and greater
cabling performance. As a result, data centres have to ensure
that their networks can cope with using 40/100 Gigabit
Ethernet (GbE).
Increased density can often result in unmanageable
cabling; fault-finding, Moves, Adds and Changes and cable
tracking may be severely hindered. An integrated hardware
and software system can automatically detect when
cords are inserted or removed. The entire infrastructure is
represented in a consistent, up-to-date database, offering
precise, real-time information on the current state and future
requirements of the data centre. Cabling infrastructure,
including connected equipment, can be documented on
an ongoing basis and monitored and admi