intermittend link down with G.703

[ROLAND CUNZ]

Hi all,

We connected two 2620 routers over a 2 Mbps link. The interfaces we use are G.703 controllers. The line is unstructured. The IOS installed on these routers are 12.1(5)T12 IP Plus 3DES. The data are 3DES encrypted and went through a VPN tunnel. The routers have built in VPN modules.

Now I recognize short interface downs/ups once or twice a week. The carrier checked the modems and the line and as they said, everything is OK.

Maybe there is anybody who can give me a hint.

Thanks in advance

Roland

[wong34539]

Most probably the interface up/down is due to link reliability. As far as with this IOS version 12.1(5)T12 there is no bugs related to VPN or 3Des encryption with interface going up and down.

You have to check the carrier.

[andreas.richter]

Hi Roland,

For me it sounds like a clocking problem. If your provider doesn't deliver clocking, one of your routers has to be configured as clock source internal., but unfortunately not every E1-controller supports this setting.