Telnet Output

jmutton has asked for the wisdom of the Perl Monks concerning the following question:

Hello there, I'm trying to grab a couple of numbers from a telnet output of a draytek router. Here is the output:

Account:admin


Password: *****

 User login successful, expired time is "Unlimited".



Type ? for command help


> wan vdsl show basic

VDSL

Link Status:    Showtime

Firmware Version:    1414c3

VDSL Profile:    17a

Basic    Status    Upstream    Downstream    Unit

Actual Data Rate:     13320      39961      Kb/s

SNR:     69      42      0.1dB

>
[download]

The two numbers that I'm interested in are the SNR values (69 and 42). Here is my code so far. Just really stuck about parsing the values to be used in a cacti graphi.

#!/usr/bin/perl
 
use Net::Telnet;

my $telnet = Net::Telnet->new(Input_log => 'telnet.log');
 
$telnet->open('192.168.1.1');
$telnet->waitfor('/Account:/');
$telnet->print('admin');
$telnet->waitfor('/Password:/');
$telnet->print('admin');

sleep(1);

$telnet->waitfor('/>/');
my @lines = $telnet->cmd('wan vdsl show basic');


#print @lines;
$telnet->close;
[download]

Comment on Telnet Output Select or Download Code

Replies are listed 'Best First'.
Re: Telnet Output by roboticus (Chancellor) on Dec 30, 2013 at 17:06 UTC
jmutton: If you just need those SNR values, you'd first find the line(s) that have the values, such as by recognizing the 'SNR:' string: `@lines = grep { /^SNR:/ } @lines;` [download] Then you could split the line on whitespace, and keep the second and third columns: `for my $line (@lines) { my ($SNR, $val1, $val2, @rest) = split /\s+/,$line; print "SNR value 1:$val1, value 2:$val2\n"; }` [download] Update: Added missing '/' in regex. (Noticed by Laurent_R) ...roboticus When your only tool is a hammer, all problems look like your thumb.	[reply] [d/l] [select]
Re: Telnet Output by atcroft (Abbot) on Dec 30, 2013 at 17:05 UTC
Here is what I would try first: `# Here be *UNTESTED* code my %snr; while ( my $line = shift @lines ) { chomp $line; if ( $line =~ m/SNR:\s+(\d+)\s+(\d+)/ ) { ( $snr{up}, $snr{down} ) = ( $1, $2 ); last; } } print q{Upstream_SNR:}, $snr{up}, q{ }, q{Downstream_SNR:}, $snr{down}, qq{\n};` [download] (The print based on a quick glance at Chapter 11 of the Cacti manual.) Hope that helps. Update: 2013-12-30 Fix typo in code (missing underscore in second field name).	[reply] [d/l]
Re^2: Telnet Output by jmutton (Initiate) on Jan 01, 2014 at 21:19 UTC
Thanks for the reply. How would it work if I had multiple SNRs? For examples `SNR Margin 60 60 (US0,--) 0.1 dB SNR Margin 61 53 (US1,DS1) 0.1 dB SNR Margin 62 50 (US2,DS2) 0.1 dB SNR Margin 0 N/A (US3,DS3) 0.1 dB SNR Margin 0 N/A (US4,DS4) 0.1 dB` [download]	[reply] [d/l]
Re^3: Telnet Output by jmutton (Initiate) on Jan 01, 2014 at 22:46 UTC
my %snr; while ( my $line = shift @lines ) { chomp $line; # (US0,--) 0.1 dB if ( $line =~ m/SNR Margin:\s(\d+)\s+(\d+)\s$US0,--$ 0.1 dB/ ) + { ( $snr{us0} ) = ( $1 ); } # (US1,DS1) 0.1 dB if ( $line =~ m/SNR Margin:\s(\d+)\s+(\d+)\s$US1,DS1$ 0.1 dB/ +) { ( $snr{us1}, $snr{ds1} ) = ( $1, $2 ); } # (US2,DS2) 0.1 dB if ( $line =~ m/SNR Margin:\s(\d+)\s+(\d+)\s$US2,DS2$ 0.1 dB/ +) { ( $snr{us2}, $snr{ds2} ) = ( $1, $2 ); } # (US3,DS3) 0.1 dB if ( $line =~ m/SNR Margin:\s(\d+)\s+(\d+)\s$US3,DS3$ 0.1 dB/ +) { ( $snr{us3}, $snr{ds3} ) = ( $1, $2 ); } # (US4,DS4) 0.1 dB if ( $line =~ m/SNR Margin:\s(\d+)\s+(\d+)\s$US4,DS4$ 0.1 dB/ +) { ( $snr{us4}, $snr{ds4} ) = ( $1, $2 ); } } print q{US0:}, $snr{us0}, qq{\n}; print q{US1:}, $snr{us1}, q{ }, q{DS1:}, $snr{ds1}, qq{\n}; print q{US2:}, $snr{us2}, q{ }, q{DS2:}, $snr{ds2}, qq{\n}; print q{US3:}, $snr{us3}, q{ }, q{DS3:}, $snr{ds3}, qq{\n}; print q{US4:}, $snr{us4}, q{ }, q{DS4:}, $snr{ds4}, qq{\n}; [download] Thats what I've managed to come up with. But I need some sort of checking as some of the SNRs will report 0 or N/A. Need it to report 0 instead of N/A.	[reply] [d/l]