Two routes connected using sync modems causing problems

[acoe]

Hello friend,

Two sites conneted via PSTN using sync modems. I am able to ping across for 20 seconds after i reboot the routers and the sync modem. After 20 seconds ping times out. Any troubleshooting tips would be highly appreciated. Here is the config of one of the router's interfaces connected to the sync modem.

interface Serial0

ip address 10.52.1.1 255.255.0.0

no ip directed-broadcast

encapsulation ppp

bandwidth 33

dialer in-band

dialer-group 1

no fair-queue

compress stac

ppp authentication chap

ppp chap hostname xxx

ppp chap password 7 xxx

pulse-time 1

Thanks

[lgijssel]

What is your clocking source?

Are the devices well synchronized to this clock?

Did you try to switch off keep-alives? Please do so (int s0, no keep)

[acoe]

Tried that no +ve results.

Thanks

[lgijssel]

When you have no result switching off keep-alives it is almost certain that you have a clocking problem. So I post my first question once again: How did you verify that your clocking is in order?

Normally, the network provides clocking to the modems. I presume that in your situation this will not be the case. Did you configure one modem as clock source? The other one will then have to derive its clock from this signal. Please investigate this issue.