Can't Ping Laptops Connected to Routers

Hello everyone …. I’m new member here, who is trying to get his CCNA.

I have set up a home lab that consists of 4 routers and 3 switches. One of the routers acted as FRS, and I have connected the other 3 routers to it forming serial links between three separate locations. My Frame Relay Sub-Interface, which has an interface-dlci assigned to it (2 in each serial interface, total of 6), work fine. All three routers can ping each other with no problems. Routers also are able to ping laptops that are connected to the routers. All laptops are able to ping IPs that are assigned to the serial sub-interfaces (Total of 6, two in each serial inetface). Two of the laptops are connected directly to their routers and the third one through a switch. VTP, VLAN and Router-on-a-Stick methods are used in connecting the 3 switches with one of the routers. 3 VLANs are configured as well, and all the routers and laptops are able to ping those VLANs.

The only issue that I have run into is the laptops are not able to ping each other’s all the time. Sometimes, one laptop is able to ping the other two, and the other two are able to ping back. Same scenario can happen to two of them. But I wasn’t able to have the three of them exchanging ping back and forth at the same time. I used RIPv1, RIPv2 and static routing in different scenarios but I got the same result.

Anybody has a clue to what I’m missing here?

Thank you in advance for your input!

Find more posts tagged with

Free for TechExams community: Cybersecurity salary guide

Compare cert salaries and plan your next career move

Button

Comments

Monkerz

Can you draw up a diagram with your setup and post your configs from the routers?

aaitech

Here is a diagram that resembles the lab topology, along with the configuration for the routers and switches.

FRS Configuration:
FRS#sh run
Building configuration...
Current configuration:
!
version 11.2
no service password-encryption
no service udp-small-servers
no service tcp-small-servers
!
hostname FRS
!
!
ip subnet-zero
no ip domain-lookup
frame-relay switching
!
interface Serial0
no ip address
no ip directed-broadcast
clockrate 64000
!
interface Serial1
no ip address
no ip directed-broadcast
encapsulation frame-relay
clockrate 64000
no frame-relay inverse-arp
frame-relay intf-type dce
frame-relay route 201 interface Serial3 102
frame-relay route 203 interface Serial2 302
!
interface Serial2
no ip address
no ip directed-broadcast
encapsulation frame-relay
clockrate 64000
no frame-relay inverse-arp
frame-relay intf-type dce
frame-relay route 301 interface Serial3 103
frame-relay route 302 interface Serial1 203
!
interface Serial3
no ip address
no ip directed-broadcast
encapsulation frame-relay
clockrate 64000
no frame-relay inverse-arp
frame-relay intf-type dce
frame-relay route 102 interface Serial1 201
frame-relay route 103 interface Serial2 301
!
interface TokenRing0
no ip address
shutdown
!
interface BRI0
no ip address
shutdown
!
no ip classless
!
!
line con 0
exec-timeout 0 0
logging synchronous
line aux 0
line vty 0 4
privilege level 15
password cisco
login
!
end

FRS#sh frame-relay route
Input Intf Input Dlci Output Intf Output Dlci Status
Serial1 201 Serial3 102 active
Serial1 203 Serial2 302 active
Serial2 301 Serial3 103 active
Serial2 302 Serial1 203 active
Serial3 102 Serial1 201 active
Serial3 103 Serial2 301 active
FRS#
__---__---__--__--__--__--__--__--__--__--__--__--__--__

R1 Configuration:

hostname R1
!
interface Ethernet0
ip address 192.168.4.1 255.255.255.0
ip directed-broadcast
!
interface Serial0
bandwidth 64
no ip address
ip directed-broadcast
encapsulation frame-relay
fair-queue 64 256 0
!
interface Serial0.2 point-to-point
bandwidth 64
ip address 172.16.1.1 255.255.255.0
ip directed-broadcast
frame-relay interface-dlci 102
!
interface Serial0.3 point-to-point
bandwidth 64
ip address 172.16.2.1 255.255.255.0
ip directed-broadcast
frame-relay interface-dlci 103
!
router rip
version 2
network 172.16.0.0
network 172.17.0.0
network 192.168.4.0
no auto-summary
!
+++++++++++++++++++++++++++++++++
R2 Configuration:

hostname R2
!
interface Ethernet0
ip address 192.168.5.1 255.255.255.0
ip directed-broadcast
!
interface Serial0
no ip address
no ip directed-broadcast
encapsulation frame-relay
!
interface Serial0.1 point-to-point
bandwidth 64
ip address 172.16.1.2 255.255.255.0
no ip directed-broadcast
frame-relay interface-dlci 201
!
interface Serial0.3 point-to-point
bandwidth 64
ip address 172.16.3.1 255.255.255.0
no ip directed-broadcast
frame-relay interface-dlci 203
!
router rip
version 2
network 172.16.0.0
network 192.168.5.0
!
ip classless
!
+++++++++++++++++++++++++++++++++++++
R3 Configuration:

hostname R3
!
interface Ethernet0/0
ip address 192.168.3.1 255.255.255.0
half-duplex
!
interface Ethernet0/0.1
description XXXX VLAN 2
encapsulation dot1Q 2
ip address 192.168.6.1 255.255.255.0
!
interface Ethernet0/0.2
description ZZZZ VLAN 3
encapsulation dot1Q 3
ip address 192.168.2.1 255.255.255.0
!
interface Serial0/0
no ip address
encapsulation frame-relay
!
interface Serial0/0.1 point-to-point
bandwidth 64
ip address 172.16.2.2 255.255.255.0
frame-relay interface-dlci 301
!
interface Serial0/0.2 point-to-point
bandwidth 64
ip address 172.16.3.2 255.255.255.0
frame-relay interface-dlci 302
!
router rip
version 2
network 172.16.0.0
network 192.168.2.0
network 192.168.3.0
network 192.168.6.0
no auto-summary
!
no ip http server
no ip http secure-server
ip classless
!
+++++++++++++++++++++++++++++++++++++++++++++++++
SW1 Configuration:

hostname SW1
!
interface FastEthernet0/1
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/2
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/3
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/11
switchport access vlan 2
!
interface FastEthernet0/16
switchport access vlan 3
!
interface VLAN1
ip address 192.168.3.10 255.255.255.0
ip directed-broadcast

++++++++++++++++++++++++++++++++++++++++++++++++++
SW2 Configuration:
hostname SW2
!
interface FastEthernet0/1
!
interface FastEthernet0/11
switchport access vlan 2
!
interface FastEthernet0/16
switchport access vlan 3
!
interface FastEthernet0/24
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface VLAN1
ip address 192.168.3.11 255.255.255.0

++++++++++++++++++++++++++++++++++++++++++++++++++

SW3 Configuration:
hostname SW3
!
interface FastEthernet0/10
!
interface FastEthernet0/11
switchport access vlan 2
!
interface FastEthernet0/16
switchport access vlan 3
!
interface FastEthernet0/24
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface VLAN1
ip address 192.168.3.12 255.255.255.0
ip directed-broadcast
!

FRS Topology.jpg

Monkerz

You have this setup as half-duplex for a reason?

hostname R3
!
interface Ethernet0/0
ip address 192.168.3.1 255.255.255.0
half-duplex

Show the interface status (sh int XXX) of Eth0/0 on R3 and whatever it connects to on SW1.

aaitech

Problem solved

After a mini marathon, trying different routers and computers, it turns out the problem is from machines that run on a MS 64-bit Operating System, a PC and 2 laptops. Yet to be figured out why is that happening!

Thanks for your suggestion ….....

Forsaken_GA

aaitech wrote: »

Problem solved

After a mini marathon, trying different routers and computers, it turns out the problem is from machines that run on a MS 64-bit Operating System, a PC and 2 laptops. Yet to be figured out why is that happening!

Thanks for your suggestion ….....

Out of curiosity, have you looked at whether or not the machines are trying ipv6 first?

Drop wireshark on the box and filter it for outgoing icmp, and then try your pings again and then check the protocol numbers to see if they're actually going via ipv4

Forsaken_GA

And also, what exactly are you trying to ping? The individual IP's, or the broadcast for the subnet? I notice some of your interfaced have ip directed-broadcast enabled, while others have it explicitly turned off.

JDMurray

One thought: Bad cable(s).

Another thought: Duplex mismatch. Is the half-duplex side of the link is getting CRC errors? Make sure both ends of each link are either set to the same duplex or autosense.

One other thought: The laptops should be connected directly to the routers using crossover cables. The router's ports should be able to detect the use of straight-through cables and compensate, but maybe something isn't working quite right in this regard.

And finally: It could be a combination of these problems.

aaitech

Thank you all for your suggestions.

- I’m trying to have all individual IPs ping each other, laptops, routers and switches, just to make sure that connection is no problem between all devices.

- To sure, I un-checked TCP/IPv6 in the Local Area Connection Property, and turned off ip directed-broadcast in all interfaces.

- I have no Duplex-mismatch problem in R3’s Int. e0/0. When I forced Full Duplex, the system gave me the mismatch error, so I have to remove it, and it went back to half duplex.

- I have no problem with the cables as well.

- I even removed the Router-on-a-Stick configuration in R3, and connected all laptops directly to the routers.

- Unfortunately, the problem persists when I put a MS 64-bit Operating System machine in this topology!!!

- I guess for now I have to stick with those 32-bit OS machines.

Best regards