Get DSL statistics from your Cisco modem

show dsl interface ATM

An example from cisco.com:

router# show dsl int atm0
Alcatel 20150 chipset information

ATU-R (DS) ATU-C (US)
Modem Status: Showtime (DMTDSL_SHOWTIME)
DSL Mode: ITU G.992.1 (G.DMT)
ITU STD NUM: 0x01 0x1
Vendor ID: 'ALCB' 'ALCB'
Vendor Specific: 0x0000 0x0000
Vendor Country: 0x00 0x0F
Capacity Used: 85% 98%
Noise Margin: 13.5 dB 7.0 dB
Output Power: 9.5 dBm 12.0 dBm
Attenuation: 1.5 dB 3.5 dB
Defect Status: None None
Last Fail Code: None
Selftest Result: 0x00
Subfunction: 0x15
Interrupts: 5940 (0 spurious)
PHY Access Err: 0
Activations: 1
SW Version: 3.670
FW Version: 0x1A04

Interleave Fast Interleave Fast
Speed (kbps): 0 8128 0 864
Reed-Solomon EC: 0 0 0 0
CRC Errors: 0 0 0 7
Header Errors: 0 0 0 2
Bit Errors: 0 0
BER Valid sec: 0 0
BER Invalid sec: 0 0

DMT Bits Per Bin
00: 0 0 0 0 0 0 0 7 6 7 9 A B C C C
10: C C C C C C B B B B A 9 A 9 0 0
20: 0 0 0 0 0 0 2 2 3 4 4 5 6 6 7 7
30: 7 8 8 8 9 9 9 A A A A A A B B B
40: B B B B B B B B B B B A B B B B
50: B B B B B B B B B B B B 2 B B B
60: B B B B B B B B B B B B B B B B
70: B B B B B B B B B B B B B B B B
80: B B B B B B B B B B B B B B B B
90: B B B B B B B B B B B B B B B B
A0: B B B B B B B B B B B B B B B B
B0: B B B B B B B B B B B B A B A A
C0: A A A A A A A A A A A A A A A A
D0: A A A A A A A A A A A 9 9 9 9 9
E0: 9 9 9 9 9 9 9 9 9 9 9 9 8 8 8 8
F0: 8 8 8 8 8 8 7 7 7 7 6 6 5 5 4 4

DSL – SNR, Attenuation, and CRC’s (taken from DSLreports.com)

SN Margin (AKA Signal-to-Noise Margin or Signal-to-Noise Ratio)
Relative strength of the DSL signal to Noise ratio. 6dB is the lowest dB manufactures specify for modem to be able to sync. In some instances interleaving can help raise the noise margin to an acceptable level. The higher the number the better for this measurement.
6dB or below is bad and will experience no sync or intermittent sync problems
7dB-10dB is fair but does not leave much room for variances in conditions
11dB-20dB is good with no sync problems
20dB-28dB is excellent
29dB or above is outstanding

Line Attenuation
Measure of how much the signal has degraded between the DSLAM and the modem. Maximum signal loss recommendation is usually about 60dB. The lower the dB the better for this measurement.
20dB and below is outstanding
20dB-30dB is excellent
30dB-40dB is very good
40dB-50dB is good
50dB-60dB is poor and may experience connectivity issues
60dB or above is bad and will experience connectivity issues

CRC Errors (Cyclic Redundancy Check)
CRC is a method of detecting errors in data transmission. A high CRC count in itself is not really cause for alarm. However, any increase in CRCs after your initial connection is established is a problem and usually points to a physical issue somewhere.

thanks again, Chris!

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