Hello , I'm trying to make a monitor that counts in and and out unicast packets : 
my $in;
my $out;
while (1){
$in = system("snmpget -Oqv -v2c -c randomstr localhost 1.3.6.1.2.1.31.
+1.1.1.7.3");
$out = system("snmpget -Oqv -v2c -c randomstr localhost 1.3.6.1.2.1.31
+.1.1.1.11.3");
system("rrdtool update opit11.rrd N:$in:$out") ;
sleep 10;
}

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When executing the code i see the number of packets on the terminal .When i execute  rrdtool fetch opit11.rrd --start -100 it shows only zeroes 0.0000000000e+00 for the time that the script was running . If somoene can point me where is my mistake ? Thank you !

In reply to Update RRD by bachoA4o

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