zabbix-agent-addons/zabbix_scripts/disco_block_devices

#!/usr/bin/perl -w

use JSON;

opendir(my $dh, "/sys/block") or die "Couldn't open /sys/block: $!";
my @blocks = grep { $_ !~ m/^\./ } readdir($dh);
closedir($dh);
my $json;
@{$json->{data}} = ();
foreach my $block (@blocks){
    my $size = 1;
    if ( -e "/sys/block/$block/size"){
        open SIZE, "/sys/block/$block/size";
        $size = join "", <SIZE>;
        close SIZE;
        chomp($size);
        next if ($size eq '0');
    }
    push @{$json->{data}}, { "{#BLOCKDEVICE}" => $block, "{#BLOCKSIZE}" => $size };
}
print to_json($json);
exit(0);