Data Center Architecture with Panduit, Intel, and Cisco

7
AN-02
There are eight SFP+ uplink ports on the Nexus 2232TM, for a 4:1 oversubscription ratio. To provide more redundancy, four
up-links can be connected to one Nexus 5000 Series switch with the remaining four uplinks connecting to a different Nexus
5000 Series switch located in either in the same cabinet or different cabinets. One Nexus 5000 Series switch can support
up to 24 Nexus 2232TM fabric extenders, but for redundancy a factor of twelve is normally used. Therefore, a typical row
with 10 to 12 server cabinets, each with (32) 1U servers and two Nexus 2232TM fabric extenders would have a switch
cabinet with two Nexus 5000 Series switches. Similarly, a row of eighteen server cabinets each with (32) 1U servers and
two Nexus 2232TM fabric extenders would have a switch cabinet with four Nexus 5000 Series switches or two switch
cabinets each with two Nexus 5000 Series switch.
Data centers with the following requirements are well suited to the ToR topology:
• New data centers without any existing cabling or equipment
• Need for scalability and ease of adding cabinets
• High-density layouts using high numbers of 1U servers per cabinet
• Reduced cable congestion
• Use with modular pre-configured cabinets
EoR Architecture
In an End-of-Row model, standard structured cabling practices are used to provide efficient cable organization. This
increases the ease of maintenance and helps reduce the chances of air flow blockage. The Nexus 2232TM and Nexus 5000
Series switches are located together in switch cabinets at either end of the row and are normally mirror images of each
other for redundancy. A typical EoR switch cabinet contains a quantity of Nexus 2232TM proportional to the number of
servers in the row. As with ToR, a ratio of one Nexus 2232TM fabric extender for every 32 servers, or one for every sixteen
servers for redundancy, is used. Like ToR, one Nexus 5000 Series switch is used per 24 (or twelve for redundancy) Nexus
2232TM fabric extenders. Using the lower ratios for redundancy, a row of eighteen server cabinets with (32) 1U servers
each would typically have two switch cabinets on either end of the row, both having eighteen Nexus 2232TM fabric
extenders and two Nexus 5000 Series switches. A row with twelve server cabinets would have either two switch cabinets,
both with twelve Nexus 2232TM and fabric extenders one Nexus 5000 Series or one switch cabinet vertically partitioned
with twelve Nexus 2232TM fabric extenders and one Nexus 5000 Series per partition. The switch cabinets or a cabinet
adjacent to the switch cabinet will generally contain multiple patch panels, called patch fields, for connection to all of the
server cabinets.
The server cabinets in the EoR architecture contain patch panels at the tops of the cabinets instead of switches or fabric
extenders. Category 6A patch cords are used to connect the patch panels to the dual-port Intel Ethernet Server Adapter
X520-T2 installed in the servers. Cabinet-to-cabinet cabling within the row connects the patch panels in the server cabinets
with the switch cabinet patch field and is generally twisted pair copper cabling such as Panduit
®
TX6A
™
10Gig
™
or TX6A-SD
™
10Gig
™
. To minimize congestion, the Panduit
®
Net-Access
™
CabRunner
®
Overhead Cable Routing System can be used with
horizontal cable managers.
End of Row architectures provide ease of replication and allow simple migration from legacy modular server access
architectures. EoR allows for central patching, which reduces oversubscription and increases full port utilization. In addition,
because all the switches are in just one or two cabinets, EoR simplifies network management and consolidates security
into fewer locations.