Troubleshooting Dial-on-Demand Routing (DDR) Issues in IGRP
Dial-on-demand routing is very common when the ISDN or similar dialup links are used as a backup link. When the primary link goes down, this backup link comes up. IGRP starts sending and receiving updates on this link as long as the primary link is down. Two ways exist for using the dialup links as a backup for the primary link: • Using the backup interface command • Using floating static routes with a dialer list that defines interesting traffic The first m..
IOS XR Basic EIGRPv6 Configuration On PE: Example
The following example shows how to configure EIGRP with a policy that filters incoming routes. This is a typical configuration for a router that has just one neighbor, but advertises other connected subnets. router eigrp 100 vrf ABC address-family ipv6 router-id 10.10.9.4 log-neighbor-changes log-neighbor-warnings &nbs..
When a Cisco IP Phone is connected to a switch port, think of the phone as another switch (which it is). If you install the phone as a part of your network, you probably can trust the QoS information relayed by the phone. However, remember that the phone also has two sources of data: ■ The VoIP packets native to the phone— The phone can control precisely what QoS information is included in the voice packets because it produces those packets. ■ The user PC data switch p..
Configuring Frame Relay Proprietary Payload Compression
The Cisco packet-by-packet payload compression can be configured on Frame Relay physical interface or on Frame Relay logical point-to-point or multipoint subinterfaces. This proprietary scheme uses the Stacker algorithm to predict the next character in a frame on a packet-by-packet basis. Hence, the dictionary is not conserved across packet boundaries. A single dictionary is used for all packets compressed on a line. This results in a lower compression ratio compared with the..
As an example of trunk configuration, consider two switches, Switch D and Switch A, which are distribution-layer and access-layer switches, respectively. The two switches are connected by a link between their Gigabit Ethernet 2/1 interfaces. This link should be configured to be a trunk carrying only VLAN numbers 100 through 105, although more VLANs exist and are used. The trunk link should use 802.1Q encapsulation, with VLAN 100 as the native VLAN. First, configure Switch-D t..
