Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

connectivity problem...

We have 3640 router with NM-4 A/S serial interface module installed in it. it was working fine with 128K leased line but when we upgraded the link to 512K the router become unstable it cannot handle heavy traffic..any help

New Member

Re: connectivity problem...

Set the Bandwidth to 512

conf t --> interface serial 0 --> Bandwidth 512


Re: connectivity problem...

you probrally are using a low speed serial card they can only handle speeds to 128K .

do a sh ver and it will show you see below , the line taht says low spped serial interface

cisco 2610 (MPC860) processor (revision 0x203) with 53248K/12288K bytes of memory.

Processor board ID JAD04170IJP (3258426822)

M860 processor: part number 0, mask 49

Bridging software.

X.25 software, Version 3.0.0.

SuperLAT software (copyright 1990 by Meridian Technology Corp).

TN3270 Emulation software.

Basic Rate ISDN software, Version 1.1.

1 Ethernet/IEEE 802.3 interface(s)

1 Serial network interface(s)

4 Low-speed serial(sync/async) network interface(s)

1 ISDN Basic Rate interface(s)

32K bytes of non-volatile configuration memory.

16384K bytes of processor board System flash (Read/Write)

Re: connectivity problem...

NM cards can handle only a max bandwidth of 128 K. If you want 512 K, then you need to put a WIC card, which can take a max of 2 MB.


New Member

Re: connectivity problem...

My problem is that when i make a back to back connection with 2 2500 series routers the protocol went down after 10 secondes;however when i put no keepalive the link protocol stay up,but no input packets.

I use cisco dce dte cable ,at the dce side i play with different clock rate the problem unsolved.

Many thanks in advance.


Re: connectivity problem...