Can not ping the gateway

Unanswered Question
Sep 12th, 2010
User Badges:

Dear all,

I set up a  network in packet trace.

PC0 :

RouterA: (fa0/0)

RouterA : (s1/0)

RouterB : (s1/0)

RouterB: (fa0/0)


PC0 andPC1 can not ping the default gateway ( I don't know why?

Thank you

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Reza Sharifi Sun, 09/12/2010 - 08:33
User Badges:
  • Super Bronze, 10000 points or more
  • Cisco Designated VIP,

    2017 LAN


Is interface fa0/0 on both routers in up and up position?

What does "sh ip int brie" shows?



Nagaraja Thanthry Sun, 09/12/2010 - 08:38
User Badges:
  • Cisco Employee,


How are you connecting the PC and the router? Are you connecting them back

to back or through the switch? If you are using the switch, are the ports

where router/PC connected in the same VLAN? Can you check the ARP cache on

the PC (arp -a) to make sure that you are seeing Router's MAC in the PC?



Richard Burts Sun, 09/12/2010 - 15:54
User Badges:
  • Super Silver, 17500 points or more
  • Hall of Fame,

    Founding Member

  • Cisco Designated VIP,

    2017 LAN, WAN

I am not able to read the attachment and so do not know if it had information that was helpful. I think that the question from Reza is an excellent starting point and relates to the question from NT about how they are connected. If the PC to router connection is not correctly set up (crossover cable if directly connected) then the router interfaces should be protocol down, and that would explain why the PCs do not ping the gateway.

In addition to those good questions I would ask if you can check and confirm how the PCs are configured? Do they have the correct gateway address configured?



johnlloyd_13 Mon, 09/13/2010 - 06:06
User Badges:
  • Blue, 1500 points or more

i remembered checking out one of the lab exercises in CCNA exploration. the weird thing about it is that the PC to router cable connection uses cross cable (one with - - -). try mixing between straight and cross cable connection until you see green light blinking. i'm sure one of them will work. 


This Discussion