I second the idea of watching debugs... 'deb ppp nego' is usually REALLY clear about what's happening. For what it's worth, though, you shouldn't need the username for the "local" router, and in my lab your configs worked as-is:
R7: interface Serial1/0 ip address 192.168.11.5 255.255.255.252 encapsulation ppp ppp authentication chap ppp chap password 0 ipexpert serial restart-delay 0 clock rate 2016000 ! username R8 password 0 ipexpert R7#show int s1/0 | i line proto|LCP|IPCP Serial1/0 is up, line protocol is up Encapsulation PPP, LCP Open Open: IPCP, CDPCP, crc 16, loopback not set R8: interface Serial1/0 ip address 192.168.11.6 255.255.255.252 encapsulation ppp ppp authentication chap ppp chap password 0 ipexpert serial restart-delay 0 ! username R7 password 0 ipexpert R8#show int s1/0 | i line proto|LCP|IPCP Serial1/0 is up, line protocol is up Encapsulation PPP, LCP Open Open: IPCP, CDPCP, crc 16, loopback not set Best Regards, Bob McCouch CCIE #38296 HerdingPackets.net On Sat, Sep 21, 2013 at 2:58 PM, Matt McAdory <[email protected]> wrote: > Have you read: > TS flow chart > > http://www.cisco.com/en/US/tech/tk713/tk507/technologies_tech_note09186a00800b4130.shtml > > general config docs > > http://www.cisco.com/en/US/tech/tk713/tk507/technologies_tech_note09186a00800b4131.shtml > > http://www.cisco.com/en/US/tech/tk713/tk507/technologies_configuration_example09186a0080094333.shtml?referring_site=bodynav > > > 'debug ppp authentication' and 'debug ppp negotiation' are your friends. > Matt > > > On Sat, Sep 21, 2013 at 8:53 AM, Christian Schröder > <[email protected]> wrote: > > Hi all, > > > > > > I have one question about PPP CHAP authentication where I don't find any > documentation explaining the following in detail. > > > > Suppose we have two routers R7 and R8 connected directly via Back2Back > serial and an encapsulation of PPP. > > > > As far as I understand the following applies: > > For the successful of a mutual CHAP authentication the following > preconditions should match. > > 1. R7 knows of a password used for its authentication against R8 > > 2. R8 knows R7s password to check for successful authentication > > and vice versa. > > > > I thought for Point 1 the configuration line "ppp chap password …" is > used > > And for Step 2 a normal username/password line is needed like in the > example below. > > > > Interestingly, this does not work until I uncomment the lines preceded > with an exclamation mark > > where the password for the router itself is configured. > > Now, I am confused about the relation between the three passwords per > side > > ("username REMOTEROUTER password PW", "username THISROUTER password PW", > "ppp chap password PW"). > > > > Why is it necessary to specify them all? > > > > > > Cheers, > > Christian > > > > > > #### On R7: > > username R8 password ipexpert > > !username R7 password ipexpert > > > > interface Serial0/0/0 > > ip address 192.168.11.5 255.255.255.252 > > encapsulation ppp > > clock rate 2000000 > > ppp authentication chap > > ppp chap password ipexpert > > > > > > > > > > #### On R8 : > > username R7 password ipexpert > > !username R8 password ipexpert > > > > interface Serial0/0/0 > > ip address 192.168.11.6 255.255.255.252 > > encapsulation ppp > > ppp authentication chap > > ppp chap password ipexpert > > > > > > > > _______________________________________________ > > For more information regarding industry leading CCIE Lab training, > please visit www.ipexpert.com > > > > Are you a CCNP or CCIE and looking for a job? Check out > www.PlatinumPlacement.com > > > > http://onlinestudylist.com/mailman/listinfo/ccie_rs > _______________________________________________ > For more information regarding industry leading CCIE Lab training, please > visit www.ipexpert.com > > Are you a CCNP or CCIE and looking for a job? Check out > www.PlatinumPlacement.com > > http://onlinestudylist.com/mailman/listinfo/ccie_rs > _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com Are you a CCNP or CCIE and looking for a job? Check out www.PlatinumPlacement.com http://onlinestudylist.com/mailman/listinfo/ccie_rs
