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Community Member

Problem with serial Interface

Good Day,

I have such problem, i have serial interface with one E1, but the problem is i cant receive E1 totally

i just receiving 1952 instead of 2048? please can anybody tell me what is the problem is ?

here is the outputs :

gw#show controllers serial 3/0

M4T: show controller:

PAS unit 0, subunit 0, f/w version 3-101, rev ID 0x2800001, version 3

idb = 0x6280A8B8, ds = 0x6280C598, ssb=0x6280C8C4

Clock mux=0x0, ucmd_ctrl=0xC, port_status=0x74

Serial config=0x8, line config=0x200

maxdgram=1608, bufpool=48Kb, 96 particles

DCD=up DSR=up DTR=up RTS=up CTS=up

line state: up

cable type : V.35 DTE cable, received clockrate 2047212

base0 registers=0x3D800000, base1 registers=0x3D802000

mxt_ds=0x645309B8, rx ring entries=47, tx ring entries=64

rxring=0xF1E09A0, rxr shadow=0x62812924, rx_head=6

txring=0xF1E0B60, txr shadow=0x62812B90, tx_head=47, tx_tail=49, tx_count=2

throttled=0, enabled=0

halted=0, last halt reason=0

Microcode fatal errors=0

rx_no_eop_err=0, rx_no_stp_err=0, rx_no_eop_stp_err=0

rx_no_buf=0, rx_soft_overrun_err=1, dump_err= 0, bogus=0, mxt_flags=0x8

tx_underrun_err=0, tx_soft_underrun_err=0, tx_limited=1(2)

tx_fullring=546116580, tx_started=-1183781241

rx_int_count=556922015, tx_int_count=-606654699

Half-duplex hdx=0x62812670, summary:-

invalid_state=0, jigged_sig=0, invalid_timeout=0, tx_drop=0

tx_int_err=0, rx_drop=0, timer_error=0, rts_timeout=0

invalid_rx=0, tx_lost_cts=0, cts_timeout=0, late_rx=0

interface Serial3/0

bandwidth 2048

ip address x.x.x.x

ip access-group 102 in

ip route-cache flow

max-reserved-bandwidth 100

serial restart-delay 0

Serial3/0 is up, line protocol is up

Hardware is M4T

Internet address is x.x.x.x/30

MTU 1500 bytes, BW 2048 Kbit, DLY 20000 usec,

reliability 255/255, txload 193/255, rxload 95/255

Encapsulation HDLC, crc 16, loopback not set

Keepalive set (10 sec)

Restart-Delay is 0 secs

Last input 00:00:01, output 00:00:00, output hang never

Last clearing of "show interface" counters 2w1d

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops:


Queueing strategy: weighted fair

Output queue: 26/1000/64/3502098 (size/max total/threshold/drops)

Conversations 23/189/256 (active/max active/max total)

Reserved Conversations 0/0 (allocated/max allocated)

Available Bandwidth 2048 kilobits/sec

5 minute input rate 770000 bits/sec, 1154 packets/sec

5 minute output rate 1553000 bits/sec, 2426 packets/sec

883999815 packets input, 1363370716 bytes, 0 no buffer

Received 0 broadcasts, 0 runts, 0 giants, 0 throttles

550 input errors, 529 CRC, 0 frame, 11 overrun, 1 ignored, 10 abort

1604098154 packets output, 827315952 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


Re: Problem with serial Interface

From the output of the show controllers command, the actual speed of the line is pretty close to E1. I guess things are ok. There is another observation though. You have a high number of output drops. You probably should refer to the document at

Community Member

Re: Problem with serial Interface


E1 consists of 32 64k channels so the total data rate is 64x32 = 2048kbps, but channel 0 is used for Synchronization and Alarm etc, so the data rate that is available end to end is 2046kbps - 64kbps.



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