PPP Configuration problem

sulfikkartm

Hai
Iam new to CCNA , when Iam configure the Encapsulation on Serial interface ,my serial interface protocol become change to down.
Iam using Encapsulation PPP.

I only did this much!
Assign IP to interfaces [e0 & s1]
then
config-if # encapsulation ppp
At the same time s1 protocol become down

Please Help me in this regard

Thanks in advance
Sulfikkar

bmauro

Well we'll need some more information first.

What is your Serial connected to?

Is it a DCE or DTE?

If I had to guess I would be that the other side is configured for HDLC (default). Once you configured your serial with PPP then the two protocols werent the same and line protocol went down. Just my guess

loboernesto

If the interface status was up and up just before you change the encapsulation to PPP the most probably things is that, as mauro said, the other side of the connection has a different encapsulation (again as mauro said hdlc ).

Use some debug ppp commands or debug interface serial to see if there's any other problem (if setting the encap back to hdlc makes the ling come back to up and up then no need for more debugging ). Sounds like a layer 2 problem so that should give you some clues.

cheers

dissolved

config t
int s0
ip address 192.168.1.1 255.255.255.252
encap ppp
clock rate 2000000<----(if you get an error, try the clockrate on the other route)
no shut


on second router:

int s0
ip address 192.168.1.2 255.255.255.252
encap ppp
no shut


Verify:
sh int s0