Physical Deals with the electrical signal. Cables, connectors, hubs, and repeaters How to Configure a Cisco Network Like all networks, a Cisco network needs to be properly configured. To do so, you need to know the configuration modes to use when configuring your network. You also should know how to configure an interface, configure a switch management interface, and configure an interface to use DHCP for your Cisco network.
|Published (Last):||7 October 2009|
|PDF File Size:||3.26 Mb|
|ePub File Size:||14.17 Mb|
|Price:||Free* [*Free Regsitration Required]|
For these steps following commands are used respectively. Basically we define a range of addresses and router search for these addresses in local interfaces. We have two options while defining the range of addresses with network command Without wildcard mask With wildcard Without wildcard Choosing this option allows us to configure the classful network.
This option is very straightforward. All we need to do is, type the network ID with network command. For example network What if I type network number instead of network ID?
For example This creates another query. Why it will be converted in Answer of this question is hidden in classful configuration. Consider following figure We have four networks Classful configuration does not understand the concept of Subnetting. In classful configuration all these networks belong to a single network. Classful configuration works only with in default boundary of mask.
Default boundary of this address is 16 bits. So it will match only first 16 bits If we want excludes serial interfaces from EIGRP, we need to configure network command with more specific information.
With wildcard In this option we provide wildcard mask along with network ID. Wildcard mask allows us to match exact networks. With wildcard we are no longer limited with default boundaries. We can match Subnetted networks as well as default networks. For example we were tasked to exclude serial interfaces in above configuration. We can use a wildcard mask of 0.
Router config-router network Now router will look for Our serial interfaces have If you are unfamiliar with wildcard mask, I suggest you to read our tutorials on ACL where we explained wildcard mask in detail with examples. Until you learn wildcard mask, use subnet mask in the place of wildcard mask. When we use Subnet mask, router converts them in wildcard mask before searching for associated interfaces.
We can look in running configuration to know what exactly being used by router. If you are a CCNA candidate or preparing for any Cisco certification, I suggest you to use wildcard mask instead of Subnet mask with network command. In real life implementation you can use either subnet mask or wildcard mask. If you use wildcard, it will be used as it is. If you use subnet mask, it will be converted in wildcard mask before using.
Router0 Router config router eigrp 20 Router config-router network We have used wildcard mask for above routers. In remaining routers we will use subnet mask. Router5 Router config router eigrp 20 Router config-router network To verify the setup we will use ping command. We have two routes between source and destination. Access the command prompt of PC1 and use ping command to test the connectivity from Server0.
After that use tracert command to print the taken path. If you are not getting same output download this configured topology and cross check with your topology to figure out the reason. EIGRP protocol automatically manages all routes for us. If one route goes down, it will automatically switch to another available route. To explain this process more clearly we have added one additional route in our network.
Currently there are two routes between PC0 and Server. You may wonder where Route2 is in this output. Till route1 is available, it will not insert route2 in routing table. When route1 is down, it will look for next possible route.
If other routes are available, it will replace current route with new route which has the lowest metric value. We can watch this process live with debug eigrp fsm command. On debug process on Router0. Router debug eigrp fsm Now suppose route1 is down.
Okay our primary route went down. What will be happen now? EIGRP will look in topology table for next available routes. If single alternative is available, it will be selected. If multiple routes are available, it will select the route with the lowest metric value. We can use show ip route eigrp command again to see the selected route.
Run tracert command again from PC0 to verify the change. Before closing just do a quick recap of important commands. Router config-router no network By default only K1 and K3 are enabled. Router config-if bandwidth 64 Set bandwidth to 64Kbps.
Used to influence the metric calculation. Router show ip eigrp neighbors Display the neighbor table in brief. Router show ip eigrp neighbors detail Display the neighbor table in detail. Used to verify whether a neighbor is configured as stub router or not. Router show ip eigrp topology.
[CCNA] Cisco Commands Cheat Sheet #3
EIGRP Configuration Step by Step Guide