Dsxpnm Serial Interface
We have a 3745 that has a DS3 connection into a frame cloud. Yesterday we noticed that the serial interface had almost 100% of bandwidth being used outbound.
I set up netflow to see what was using it, and it wasn't consistent. I tried to block ports and servers in an acl, and I applied it inbound on the serial interface, but that didn't make a difference. John While you might try something like IP accounting to categorize and identify the traffic, I think that NetFlow is the optimum tool for this purpose. 
Are you reading the NetFlow results manually on the router or are you exporting NetFlow to some device that gathers data and reports results over some time period (the better solution)? Does the code that you are running support the NetFlow top talker functionality? If so that would be the easy way to find what is generating the most traffic.
Errors on T3 Interfaces. We just switched over to a frac T3. Hardware is DSXPNM Serial Internet address is y.y.y.162/30 MTU 4470 bytes, BW 12631 Kbit. DS3 connectiob b/w 7. I have a cisco 7. VXR with a DS3 card PA- T3+ (From Mpls) to a cisco 3. NM- 1te/E3 port adapter. 5, I have the folowing code on the card. The 4-port serial HWICs have 26-pin 12-in-1 Cisco smart serial ports, whereas the 8- and 16-port serial HWICs have 68-pin serial ports. Use the correct cable for your serial HWIC. Use the correct cable for your serial HWIC.
Com Port Settings Windows 10
Your original post talked about bandwidth (which is just administrative) and about dsu bandwidth which could be a controller command and if so is more than just administrative. Could you post the controller/service module (if present) and interface configuration? Rick, I'm using the free version of Solarwinds Netflow to collect. I set up top talkers on the router, but the data isn't consistent with what I'm seeing on the output of the interface.
Serial Interface Software
For instance, my top 10 doesn't equal 80% of the bandwidth (all of them are maxing out at a certain kb, but only equates to about 2mb of speed). I don't have a collector that can write to a database for trending. Here's the controller and interface information: controller T1 0/0 framing esf linecode b8zs channel-group 0 timeslots 1-24 speed 64! Controller T1 0/1 framing esf linecode b8zs channel-group 0 timeslots 1-24 speed 64! Controller T3 1/0 clock source line! Interface Serial1/0 description DS3 connection for the GO no ip address encapsulation frame-relay IETF no ip route-cache cef no ip mroute-cache load-interval 30 dsu bandwidth 44210 frame-relay lmi-type cisco interface Serial1/0.115 point-to-point description DS3 connection for the GO ip address 172.x.x.1 255.x.x.x frame-relay interface-dlci 1002 Thanks!