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Cant ping my Serial interface (UP/UP)

Hi,

I have a strange problem...... happend 10 days ago, it was working fine before that.

I have VSAT link connected to HUB, We use normal SCPC/DVB technology.
I have a Cisco router 1721 with 1 WIC + 1 Eth
My serial is UP/UP
my link is working fine...... any thing is working....EXCEPT ICMP packets.

My problem is:
I cant ping any site??? I cant even ping my serial interface??!!!!
I can ping my Eth0.....or any device connected through Eth0..... but no thing through Serial0????
At the same time all other serivces are working fine (Http, FTP, SMTP, POP....etc) EXCEPT ICMP???


==========================================================
Find below my router configration:-
Building configuration...

Current configuration : 1095 bytes
!
version 12.2
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname XXXXX
!
enable secret 5 XXXXXXXX
!
ip subnet-zero
no ip domain-lookup
!
!
!
!
!
interface FastEthernet0
 description connected to EthernetLAN
 ip address X.X.X.X  255.255.255.248
 speed auto
!
interface Serial0
 bandwidth 128
 no ip address
 encapsulation frame-relay IETF
 load-interval 30
 no keepalive
 no fair-queue
 ignore-dcd
 serial restart_delay 0
 cdp enable
!
interface Serial0.1 point-to-point
 bandwidth 128
 ip address X.X.X.X 255.255.255.252
 frame-relay interface-dlci 101 IETF
!
ip classless
ip route 0.0.0.0 0.0.0.0 X.X.X.X
no ip http server
!
!
!
line con 0
 exec-timeout 0 0
 password 7 XXXX
 login
line aux 0
line vty 0 4
 password 7 XXXX
 login
!
no scheduler allocate
end


==========================================================

I believe it is ISP problem (HUB problem)...... but I cant understand that I cant ping my serial??!!!!!

0
princeofsudan
Asked:
princeofsudan
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1 Solution
 
Don JohnstonInstructorCommented:
You serial 0 isn't really up/up. It thinks it is though. Your problem is that your router isn't sending any frame-relay LMI's. To turn them on:

conf t
int s0
keepalive 10
end

Then give it about a minute.
0
 
princeofsudanAuthor Commented:
I want to confirm one thing...That my link is working, Serial0 Up/Up..... I can browse internet nad do eny thing EXCEPT ICMP.

But, I did what you told me to do, but I lose the connection to router, I had to go back to my normal configration.

What is make very strange that I ping site from internet.... but I cant ping internet from inside router??? I aslo cant ping my serial interface!!!!
0
 
Don JohnstonInstructorCommented:
How are you accessing the VSAT link?

How are you accessign the internet?

Can you provide a topology diagram?
0
 
Scotty_ciscoCommented:
when your pinging from the router have you tried an extended ping?  Not knowing the address if you have a private non routable address on the serial interface and you ping from that you most likley are not going to get a responce

try this

ping (enter)
protocol (enter)
destination (some IP address)
keep doing that and follow the questions when it askes if you want extended options hit y and enter
it will ask for a source interface use the IP on the ethernet.
then just keep hitting enter until the ping starts the defaults are fine for the remainder of this test.

I have worked in VSAT enviroments previously and your latency is usually around the 600ms anyway so if your ICMP timeout is less than 2 or so seconds and it's a slow site the ICMP could be timing out.

Thanks
scott
0
 
princeofsudanAuthor Commented:
Dear All,

Thanks for tring help me.... but as I believed, it is HUB problem, they fix the problem.

It is working fine now.

Thanks again.
0
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