Configuring Ether Channel Load Balancing

The hashing operation can be performed on either MAC or IP addresses and can be based solely on source or destination addresses, or both. Use the following command to configure frame distribution for all EtherChannel switch links Switch(config) port-channel load-balance method Notice that the load-balancing method is set with a global configuration command. You must set the method globally for the switch, not on a per-port basis. Table 7-3 lists the possible values for the method variable,...

Modular Network Design

Server Block Cisco

Recall from Chapter 1, Campus Network Overview, that a network is best constructed and maintained using a three-tiered hierarchical approach. Making a given network conform to a layered architecture might seem a little confusing. You can design a campus network in a logical manner, using a modular approach. In this approach, each layer of the hierarchical network model can be broken into basic functional units. These units, or modules, then can be sized appropriately and connected, while...

Hot Standby Router Protocol

HSRP is a Cisco-proprietary protocol developed to allow several routers (or multilayer switches) to appear as a single gateway IP address. RFC 2281 describes this protocol in more detail. Basically, each of the routers that provides redundancy for a given gateway address is assigned to a common HSRP group. One router is elected as the primary, or active, HSRP router another is elected as the standby HSRP router and all the others remain in the listen HSRP state. The routers exchange HSRP hello...

Layer 3 QoS Classification with DSCP

From the beginning, IP packets have always had a type of service (ToS) byte that can be used to mark packets. This byte is divided into a 3-bit IP Precedence value and a 4-bit ToS value. This offers a rather limited mechanism for QoS because only the 3 bits of IP Precedence are used to describe the per-hop QoS behavior. The DiffServ model keeps the existing IP ToS byte but uses it in a more scalable fashion. This byte also is referred to as the Differentiated Services (DS) field, with a...