Shell Programming and Scripting

Hi there,

I would like to have some assistance with 2 problems I have.
Well, let's call it 2 challenges.
The language to use is Perl.

First is a foreach loop (or any other suggestion).
I want to have a list of IP addresses and exit when an extracted IP address is not in that list.
It is important to have the IP's listed line by line.
Here a first try, but it gives an error:

foreach my $i (
"10.216.74.137"
"10.216.74.144"
"10.216.74.148"
) {
return 0 unless ( $agent_address eq $i );
}

Second "challenge" is to retrieve the last part of a line:

This is the line (part of a bigger message):

enterprises.alcatel.nmu.genos.alarmHandoff.alarmHandoffObjects.alarmTable.alarmEntry.probableCause.3 200904 = Replaceable Unit Missing

Currently I have this:

my $probablecause;
if ($msg_line[15] =~ m/probableCause.*\.(.*)$/) {
$probablecause=$1;
}

But this returns everything after the search string probableCause.
The number behind probableCause always differs.
The output should be "Replaceable Unit Missing".

Many thanks in advance,

Erik

Just a couple of suggestions that may help you.

I would put the IP address into an array. The loop through and look for the agent_address:

i.e.

@ips = qw(10.216.74.137 10.216.74.144 10.216.74.148);
$agent_address = "10.216.74.144";
foreach(@ips) {
print "$_\n" if(/$agent_address/);
}

And for the second one, maybe using a search\replace regex to grab the end of the string:

i.e.


$probablecause = "enterprises.alcatel.nmu.genos.alarmHandoff.alarmHandoffObjects.alarmTable.alarmEntry.probableCause. 3 200904 = Replaceable Unit Missing";
$probablecause =~ s/.*probableCause.*\s=\s(.*)/$1/;
print "$probablecause\n";

Hope this helps.

If they wanted to check the entire IP address for an exact match they would use "eq" instead of a regexp:

Code:

@ips = qw(10.216.74.137 10.216.74.144 10.216.74.148);
$agent_address = "10.216.74.144";
foreach(@ips) {
   print "$_\n" if ($_ eq $agent_address);
}

Your way will find false positives especially because the dot character in the IP addresses will be interpreted as a wild card character in the regexp instead of a dot. You would want to use the \Q option to avoid that interpretation of the dot in an m// regexp.

Personally I do not understand this requirement:

Code:

I want to have a list of IP addresses and exit when an extracted IP address is not in that list.

"Exit" what? The only way to make sure the IP address is not in the list is to check the entire list, unless the list is in some type of order and you know once you get passed a certain part of the list the IP address can no longer be in the list. Like the letter "c" can not be past the letter "d" in an alpha sorted list of a-z.

Assuming the dot is always present after probableCause in the string:

Code:

$msg_line = 'enterprises.alcatel.nmu.genos.alarmHandoff.alarmHandoffObjects.alarmTable.alarmEntry.probableCause.3 200904 = Replaceable Unit Missing';
my $probablecause;
if ($msg_line =~ m/probableCause\.(?:[\d ]*)=([\S\s]+)$/) {
   $probablecause = $1 || 'no match';
}
print $probablecause;

Hi,

Thanks to you both.

The first problem is solved with this:

my $continue = 0;
@ips = qw(
10.216.66.137
10.216.74.137
10.216.74.144
10.216.74.148
);
foreach(@ips) {
if ( $agent_address eq $_ ) { $continue = 1 };
}
return 0 unless $continue;


The second problem is solved with this:

my $probablecause;
if ($msg_line[15] =~ m/probableCause\.(?:[\d ]*)=([\S\s]+)$/) {
$probablecause=$1;
}

This because the last suggestion is a bit shorter and can be reused more easily.

Works great. Does the trick for me.

Erik

Okay, perhaps one more thing.
One of the SNMP trap lines is as follows:

enterprises.alcatel.nmu.genos.alarmHandoff.alarmHandoffObjects.alarmTable.alarmEntry.currentAlarmId. 3200904 = Counter32: 3200904

This code:

my $currentalarmid;
if ($msg_line[11] =~ m/currentAlarmId\.(?:[\d ]*)=([\S\s]+)$/) {
$currentalarmid=$1;
}

returns this value:

Counter32: 3200904

Which is of course correct.
I would like to have the value 3200904 only.

Of course the value 3200904 in the line changes all the time.
The rest of the line is fixed.

Would I completely understand the magic in "\.(?:[\d ]*)=([\S\s]+)$/" I may solve it myself, but since I don't .............

Any suggestions ?

Regards,

Erik

Code:

if ($msg_line[11] =~ m/currentAlarmId\.(?:[\d ]*)= Counter32: (\d+)$/)

How simple some things can be :-)

Thanks.