Specifications

Chapter 3. Reference architectures 111
Figure 3-2 shows a Layer 1 architecture with the host names and interfaces used for
inter-switch connections.
Figure 3-2 Top-of-Rack - Layer 1 architecture
3.2.2 Layer 2 architecture
Top-of-Rack architecture brings routing down to the access layer, which means that Layer 2,
or the Spanning Tree Protocol (STP) domain, terminates at access layer switches (ACC-1
and ACC-2).
Virtual Local Area Networks
Table 3-3 shows Virtual Local Area Networks (VLANs) used in the topology and the member
ports of those VLANs.
Table 3-3 VLANs and port assignment
Aggregation
Layer
Access
Layer
Server
IBM System
x3550 M3
port1
port3
port6
port5
port2
port4
port5
port6
port1 port2
port4
port3
port7
port7
ACC-1
ACC-2
AGG-1
AGG-2
port20
port19
port17 port18
port1
port5
port1
port5
port17
port18
port20
port19
SRV-1
40 Gbps
10 Gbps
NIC0 NIC1
VLAN number VLAN name Description Member ports
VLAN4095 Mgmt VLAN Management
VLAN
ACC-1, port127 (untagged)
ACC-2, port127(untagged)
VLAN10 Server 1 VLAN VLAN for Server
farm 1
ACC-1, port5 (tagged)
ACC-1, port6 (tagged)
ACC-1, port7 (untagged)
ACC-2, port5 (tagged)
ACC-2, port6 (tagged)
ACC-2, port7 (untagged)