Ping command result

[noxkrugger]

Can somebody explain to me what is the output of this pattern of ping result?

1) U.U.U

2) UUUUU

3) .....

4) HHHHH

[Goutam Sanyal]

Hi,

Pls cover the CCNA book carefuly.

Rgds

Goutam S

[williamsdo]

Hi. the U result is from an ICMP packet host unreachable, could be a result of route summarization if you are using EIGRP. Try a show IP route and see if the network you are trying to reach is in the routing table, if not check your routing IP protocols for summary enable, if so you can disable it with no auto-summary command.

As you study for your CCNA and CCNP exams, particularly if you're getting hands-on practice in your home lab or rack rental service, you're going to be sending a lot of pings. As a CCNA or CCNP candidate, you know that five exclamation points (!!!!!) as a ping return indicates that you have IP connectivity to the remote destination. Five periods (.....) indicates that you do not have that connectivity. The ping return of "U.U.U" is a general indication that the packets are indeed being transmitted, but that a downstream router is having a problem routing the packets.

HTH

[architetto]

Implementation of an ACL denying access to an interface/network would also bring this result.

[chukwuma]

I am having same experience. 

I Heartily appreciate and understand this you response. 

But please how can someone solve the problem that gives U.U.U error message!

[Richard Burts]

We do not know enough about your environment to be able to give much advice. One thing that I can offer is that the pattern of U.U.U indicates that your device believes that there are 2 paths that can get to the destination, and that neither path actually gets to the destination. Your ping request first packet goes on one path and somewhere on that path a device sends an ICMP response that the destination host is not reachable. Your ping next request goes on the other path and there is no response at all. Your ping third request is like the first and gets the same response. Your ping fourth request is like the second and gets no response. Your fifth request is like the first and third and gets the same response.

If you want more advice about this problem then you need to give us more information. What kind of device is generating the ping requests? Post the output of show ip route. What is the destination IP that you are attempting to ping?

[Goutam Sanyal]

"U" = Destinnation Unreachable

"." = The Network server/service timed out while waiting for a reply

"H" = Host unreachable

"P" = Protocol "

"N" = Network "

"!" = Receipt of a reply

"Q" = Source quench

"M" = Could not fragment

"?" = Unknown packet type

Hope it'll help you out.

Rgds

Goutam S