how to configured two routers cisco 1841 leased line configuation with steps
Cisco 1841 Leased Line Configuration Between Two Routers
This example shows how to configure a leased line connection between two Cisco 1841 Integrated Services Router routers using a serial interface.
Network Diagram
PC1 ---- Router1 ===== Serial Leased Line ===== Router2 ---- PC2
Fa0/0 Fa0/0
Example IP Addressing
| Device | Interface | IP Address | Subnet Mask |
|---|---|---|---|
| Router1 | FastEthernet0/0 | 192.168.1.1 | 255.255.255.0 |
| Router1 | Serial0/0/0 | 10.0.0.1 | 255.255.255.252 |
| Router2 | FastEthernet0/0 | 192.168.2.1 | 255.255.255.0 |
| Router2 | Serial0/0/0 | 10.0.0.2 | 255.255.255.252 |
Required Devices
2 Cisco 1841 Routers
Serial DCE/DTE Cable
Console Cable
2 PCs
Packet Tracer or real routers
Step 1: Connect the Routers
Connections
| Device | Port | Connected To |
|---|---|---|
| Router1 | Serial0/0/0 | Router2 Serial0/0/0 |
| PC1 | Fa0/0 | Router1 Fa0/0 |
| PC2 | Fa0/0 | Router2 Fa0/0 |
Step 2: Configure Router1
Enter privileged mode:
enable
configure terminal
Configure FastEthernet Interface
interface fastethernet0/0
ip address 192.168.1.1 255.255.255.0
no shutdown
exit
Configure Serial Interface
interface serial0/0/0
ip address 10.0.0.1 255.255.255.252
clock rate 64000
no shutdown
exit
Configure
clock rateonly on the DCE side.
Configure Static Route
ip route 192.168.2.0 255.255.255.0 10.0.0.2
Save Configuration
end
write memory
Step 3: Configure Router2
enable
configure terminal
Configure FastEthernet Interface
interface fastethernet0/0
ip address 192.168.2.1 255.255.255.0
no shutdown
exit
Configure Serial Interface
interface serial0/0/0
ip address 10.0.0.2 255.255.255.252
no shutdown
exit
Configure Static Route
ip route 192.168.1.0 255.255.255.0 10.0.0.1
Save Configuration
end
write memory
Step 4: Configure PCs
PC1
| Setting | Value |
|---|---|
| IP Address | 192.168.1.2 |
| Subnet Mask | 255.255.255.0 |
| Default Gateway | 192.168.1.1 |
PC2
| Setting | Value |
|---|---|
| IP Address | 192.168.2.2 |
| Subnet Mask | 255.255.255.0 |
| Default Gateway | 192.168.2.1 |
Step 5: Verify Connection
Check Interfaces
show ip interface brief
Interfaces should show:
up/up
Test Ping
From Router1:
ping 10.0.0.2
From PC1:
ping 192.168.2.2
Step 6: Verify Routing Table
show ip route
You should see static routes configured.
Important Commands
| Command | Purpose |
|---|---|
show controllers serial 0/0/0 | Check DCE/DTE side |
show running-config | View current configuration |
show ip route | View routing table |
show ip interface brief | Check interface status |
Troubleshooting Tips
If Serial Interface is Down
Use:
no shutdown
If Encapsulation Mismatch Occurs
Configure both routers:
interface serial0/0/0
encapsulation ppp
Or use default HDLC on both sides.
If Ping Fails
Check:
IP addresses
Static routes
Serial cable connection
Interface status
Clock rate on DCE router
Example Complete Router1 Configuration
hostname Router1
interface fastethernet0/0
ip address 192.168.1.1 255.255.255.0
no shutdown
interface serial0/0/0
ip address 10.0.0.1 255.255.255.252
clock rate 64000
no shutdown
ip route 192.168.2.0 255.255.255.0 10.0.0.2
Example Complete Router2 Configuration
hostname Router2
interface fastethernet0/0
ip address 192.168.2.1 255.255.255.0
no shutdown
interface serial0/0/0
ip address 10.0.0.2 255.255.255.252
no shutdown
ip route 192.168.1.0 255.255.255.0 10.0.0.1