zabbix-agent-addons/zabbix_scripts/disco_filesystems

#!/usr/bin/perl

use JSON;
my $json;
@{$json->{data}} = ();

my $cmd;
my $re;
# On Linux, parse /proc/mounts
if (-e "/proc/mounts"){
    $cmd = 'cat /proc/mounts';
    $re = qr/(\S+) (\S+) (\S+)/;
}
# On BSD (at least pfsense), there's no /proc/mounts
# parse the mount output
else{
    $cmd = '/sbin/mount';
    $re = qr/(\S+) on (\S+) \((\S+), /;
}
for (`$cmd`){
    ($block, $fsname, $fstype) = m/$re/;
    # Default warning and critical level (%)
    my $warning = 85;
    my $critical = 95;
    my $t;
    if (open WARN, "$fsname/.zbx_warning"){
       $t = join "", <WARN>;
       close WARN;
       chomp($t);
       $warning = $t if ($t =~ m/^\d+$/);
    }
    if (open CRIT, "$fsname/.zbx_critical"){
       $t = join "", <CRIT>;
       close CRIT;
       chomp($t);
       $critical = $t if ($t =~ m/^\d+$/);
    }

    push @{$json->{data}}, {
      "{#FSNAME}"      => $fsname,
      "{#FSTYPE}"      => $fstype,
      "{#FSDEVICE}"    => $block,
      "{#FSWARNTHRES}" => $warning,
      "{#FSCRITTHRES}" => $critical
    };
}

print to_json($json);
exit(0);