atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services T1's, CSU's and DSU's T1 slow in one direction and fast in the other

If I can add to this, I'd suggest that you also realize that there just may be more utilization in one direction than the other which of course will lower session performance in some cases.

When testing, be sure to disconnect the LAN at both ends and test from notebook to notebook to rule out the network as a possible issue. Once the WAN is proved clean, you can focus on what on the LAN is utilizing the bandwidth.

Hope this helps.

Fred

Hello all,

I have an identical issue, on a point-to-point T1 we have running between our Portland and Boise offices. Very slow from Portland to Boise.

This is what our traffic for the past week looks like (Boise to Portland in Green, Portland to Boise in Blue):



The show interface output on the serial interfaces looks like this...

Portland show int s0:
Serial0 is up, line protocol is up
Hardware is PQUICC with Fractional T1 CSU/DSU
Description: PLDHGL572789ELG, Oliver Russell and Associates Portland, Chris Hillman, 208-XXX-XXXX
Internet address is 172.17.0.2/30
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
reliability 255/255, txload 46/255, rxload 51/255
Encapsulation HDLC, loopback not set
Keepalive set (10 sec)
Last input 00:00:01, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/11/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
5 minute input rate 312000 bits/sec, 44 packets/sec
5 minute output rate 283000 bits/sec, 31 packets/sec
18213621 packets input, 676783642 bytes, 0 no buffer
Received 188156 broadcasts, 4 runts, 0 giants, 0 throttles
70660 input errors, 41308 CRC, 29291 frame, 0 overrun, 0 ignored, 59 abort
11486369 packets output, 3019233377 bytes, 0 underruns
0 output errors, 0 collisions, 5 interface resets
0 output buffer failures, 0 output buffers swapped out
5 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up


Boise show int s0
Serial0 is up, line protocol is up
Hardware is PQUICC with Fractional T1 CSU/DSU
Description: PLDHGL572789ELG, Oliver Russell and Associates Boise, Chris Hillman, 208-XXX-XXXX
Internet address is 172.17.0.1/30
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
reliability 255/255, txload 48/255, rxload 46/255
Encapsulation HDLC, loopback not set
Keepalive set (10 sec)
Last input 00:00:05, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 1760
Queueing strategy: weighted fair
Output queue: 0/1000/64/1759 (size/max total/threshold/drops)
Conversations 0/10/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
Available Bandwidth 1158 kilobits/sec
5 minute input rate 279000 bits/sec, 26 packets/sec
5 minute output rate 294000 bits/sec, 45 packets/sec
11482616 packets input, 3016171101 bytes, 0 no buffer
Received 188140 broadcasts, 0 runts, 1 giants, 0 throttles
11244 input errors, 438 CRC, 4932 frame, 0 overrun, 0 ignored, 5874 abort
18208562 packets output, 672502468 bytes, 0 underruns
0 output errors, 0 collisions, 5 interface resets
0 output buffer failures, 0 output buffers swapped out
5 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up

The bolded section is what I'm concerned about. Any thoughts on troubleshooting?.. could a bad cable in Boise or Portland cause errors on both routers?

Any help appreciated.

Thanks,
Chris

Please start a new post. I will tell you this, you need to test CSU to CSU and not run packets of data as this is not testing the T-1.

Looks like a timing issue. If you have CRC errors, that is usually what that means..

Let's let him start a new thread with his problem instead of bringing up an old one. It makes it too confusing especially if someone does a search to try to resolve their problem.