Subversion Repositories sysadmin_scripts

#! /usr/bin/env perl

# finds missing drives, telling you what bay they are in.

# Author: R. W. Rodolico

# Date: 2025-04-04

#

# run smartctl --scan to determine what drives are in the system, then

# again for each drive to get the serial number off of the drives.

# These end up in @active

#

# If there is stuff in STDIN, will assume that is the input and 

# search it for lines which do not match the list of serial numbers

# from @active.

#

# If STDIN is not active, looks for either of the files 'drive_bays', 

# then 'drives.tsv' in both /etc and /usr/local/etc. If one of those

# is found, will read it in, searching lines which do not match the list

# of serial numbers in @active

# 

# Any matching lines (those not found in @active) are printed to the

# screen

#

use strict;

use warnings;

use IO::Select; # this appears to be available in base Perl installs

sub loadFile {

   my ( $filename, $regex, @paths ) = @_;

   my @return;

   while ( my $path = shift @paths ) {

      if ( -f "$path\/$filename" ) {

         open DATA, "<$path\/$filename" or die "Could not open $path\/$filename: $!\n";

         @return = grep{ ! /$regex/ } <DATA>;

         chomp @return;

         return @return;

      }

   }

   return undef;

}

# get list of active drives from smartctl

my @drives = qx( smartctl --scan | cut -d' ' -f1 );

chomp @drives;

my @active;

# for each drive found, get its serial number. Note: using geom might be faster

foreach  my $drive ( @drives ) {

   push @active, qx( smartctl -a $drive | grep 'Serial Number:' | rev | cut -d' ' -f1 | rev );

}

chomp @active;

# build a regex that contains all of the serial numbers found

my $regex = '(' . join( '|', @active ) . ')';

my @lines; # a place to put our input

# turn off STDIN for blocking read

my $selector = IO::Select->new();

$selector->add(\*STDIN);

if ( $selector->can_read(0) ) { # This is true only if there is something on STDIN, ie a pipe

   @lines = grep{ ! /$regex/ } <>;

} 

# if STDIN didn't work, look for file drive_bays

@lines = &loadFile( 'drive_bays', $regex, '/etc', '/usr/local/etc' ) unless @lines;

# if we still didn't do it, try the file drives.tsv

@lines = &loadFile( 'drives.tsv', $regex, '/etc', '/usr/local/etc' ) unless @lines;

# OMG, nothing worked. Tell the user

push @lines, "Could not find STDIN, drive_bays or drives.tsv, no values" unless @lines;

chomp @lines;

print join("\n", @lines) . "\n";

1;