Information Technology Reference
In-Depth Information
10 Gigabit Ethernet
Gigabit Ethernet or Etherchannel
Backup
Campus Core
DC
Core
DC
Aggregation
Aggregation 2
Aggregation 3
Aggregation 4
DC
Access
Layer 2 Access with
Clustering and NIC
Te a m i n g
Blade Chassis with
Passthru Modules
Mainframe
with OSA
Blade Chassis
with Integrated
Switch
Layer 3 Access with
Small Broadcast Domains
and Isolated Servers
Figure 4-9
Data Center Access Layer
New routed access designs aim to contain Layer 2 locally to avoid the use of the STP.
With routed access designs, the default gateway function needs to be provided because
the access switch becomes the first-hop router in the network.
Designs with both Layer 2 and Layer 3 access provide flexibility for multiple server solu-
tions to be supported, including 1RU servers and modular blade server chassis.
Here are some of the data center access layer benefits:
Provides port density for server farms
■
Supports single homed and dual homed servers
■
Provides high-performance, low-latency Layer 2 switching
■
Supports mix of oversubscription requirements
■
