Update httpd.conf IPs from DNS zones.

[bigb89]

Hi guys,

Here's what I'm trying to accomplish:
I have VirtualHost entries on my httpd.conf that looks similar to the following:

<VirtualHost 301.163.169.211:80>
    ServerName accounttest.com
    ServerAlias www.accounttest.com
    ServerAdmin webmaster@accounttest.com
    DocumentRoot /home/accountt/public_html
    <IfModule mod_suphp.c>
        suPHP_UserGroup accountt accountt
    </IfModule>
    <IfModule !mod_disable_suexec.c>
        User accountt
        Group accountt
    </IfModule>
    BytesLog /usr/local/apache/domlogs/accounttest.com-bytes_log
    CustomLog /usr/local/apache/domlogs/accounttest.com combined
    ScriptAlias /cgi-bin/ /home/accountt/public_html/cgi-bin/
    # To customize this VirtualHost use an include file at the following locatio
n
    # Include "/usr/local/apache/conf/userdata/accountt/accounttest.com/*.conf"
</VirtualHost>

And I have zone files that looks similar to this:

; cPanel 11.24.0-CURRENT_30944
; Zone file for accounttest.com
$TTL 14400
@      86400    IN      SOA     ns5.domain.com. cpm.domain.com. (
                2008111802      ; serial, todays date+todays
                86400           ; refresh, seconds
                7200            ; retry, seconds
                3600000         ; expire, seconds
                86400 )         ; minimum, seconds

accounttest.com. 86400 IN NS ns5.domain.com.
accounttest.com. 86400 IN NS ns6.domain.com.


accounttest.com. IN A 35.45.68.21

localhost.accounttest.com. IN A 127.0.0.1

accounttest.com. IN MX 0 accounttest.com.

mail IN CNAME accounttest.com.
www IN CNAME accounttest.com.
ftp IN A 35.45.68.21

As you can see, the IP that's on the zone file does not match the IP that's on httpd.conf virtualhost entry. So I would like to do the following:

1) How can I grab the IP from this line: accounttest.com. IN A 35.45.68.21
In the above line, the IP would be 35.45.68.21 (so the $4 variable of the line I guess)

2) Then how can I use the variable $4 from the line above and replace the IP that's being used by the VirtualHost entry of accounttest.com? So the VirtualHost entry would look like this:

<VirtualHost 35.45.68.21>
ServerName accounttest.com
...
...

I'm sorry if this sounds confusing. I kinda have an idea of what needs to be done, but I don't know where to start. Any help will be very appreciated.

[J65nko]

To get you started

$ cat source1
accounttest.com. IN A 35.45.68.21

$ cat source2
gorilla.org.  IN A 11.22.33.44

$ cat zone2vhost                                             

#!/bin/sh

FILE="$1"

IP=$(awk '/^[^ ]+ +IN +A +/ { print $4 }' <${FILE} )
name=$(awk '/^[^ ]+ +IN +A +/ { print $1 }' <${FILE} )

NAME=$( echo ${name} | sed -e 's!\.$!!' )
#echo $IP
#echo $NAME

cat <<END
<VirtualHost ${IP} >
  ServerName ${NAME} 
  ServerAdmin webmaster@${NAME}
  DocumentRoot /www/docs/${NAME}
  ErrorLog logs/error_${NAME}.log
</VirtualHost>

END

$ for FILE in source1 source2 ; do zone2vhost ${FILE} ; done 

<VirtualHost 35.45.68.21 >
  ServerName accounttest.com 
  ServerAdmin webmaster@accounttest.com
  DocumentRoot /www/docs/accounttest.com
  ErrorLog logs/error_accounttest.com.log
</VirtualHost>

<VirtualHost 11.22.33.44 >
  ServerName gorilla.org 
  ServerAdmin webmaster@gorilla.org
  DocumentRoot /www/docs/gorilla.org
  ErrorLog logs/error_gorilla.org.log
</VirtualHost>

There is a slight problem if there are more IN A records in a file, or when the delimiters are not spaces but tabs

Actually it would be better to first extract all IN A records into a separate file. After the file has been checked for sanity, then process it.

[bigb89]

Actually it would be better to first extract all IN A records into a separate file. After the file has been checked for sanity, then process it.

That sounds like a good idea J65nko.

I'm a not an experienced programmer, so here's my question:

How can I extract the A record lines from the zone files and add them in to a separate file?

This is the line I would like to extract from the zone files:
someDomain.com. IN A someIP

The first delimiter would be the domain name and the fourth would be whatever IP the domain is using. Then based on that, the script would search httpd.conf for: ServerName\ $1. ($1 would be someDomain.com in this case). Once it finds that, it looks for the line above ServerName which is: VirtualHost 0.0.0.0. Then it would replace 0.0.0.0 with $4 which would be someIP from the dns zone file.

[J65nko]

$ cat extract
#!/bin/sh

# match IN A record from DNS zone file

egrep "^[^[:blank:]]+[[:blank:]]+IN[[:blank:]]+A[[:blank:]]+\
[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}" $1    

#       ^               : beginning of line
#       [               : start of character class
#       ^[:blank:]      : not (space or horizontal tab)
#       ]               : end character class
#       +               : one or more of preeceding atom
#                         One or more non-blanks at beginning 
#                         of line = domain name 

#       [               : start of character class
#       [:blank:]+      : one or more spaces or horiz tabs
#       ]               : end character class
#       IN              : followed by I and an N
#       [[:blank:]]+    : one or more spaces or horiz tabs
#       A               : A
#       [[:blank:]]+    : one or more spaces or horiz tabs
# 
#  Matching the IP number
#
#       [0-9]           : a digit
#       {1,3}           : of the preceding atom at least one, at most 3
#       \.              : a period '.'
#                         because '.' in a regex pattern stands for 'any character'
#                         we have to use a "\" to tell the regex machine that we 
#                         want to match a literal "."
#       
#       [0-9]{1,3}\.    : second octet of IP number followed by a period
#       [0-9]{1,3}\.    : third octet of IP number followed by a period
#       [0-9]{1,3}      : fourth and last octet of IP number

A sample run on your example zone file:

$ ./extract zone-example       
accounttest.com. IN A 35.45.68.21
localhost.accounttest.com. IN A 127.0.0.1
ftp IN A 35.45.68.21

So we already have a slight problem here Houston

Do you keep those zone files in a directory you can do something like what I did in my first post: use the files in a loop calling the extracting script.

[bigb89]

So we already have a slight problem here Houston

Do you keep those zone files in a directory you can do something like what I did in my first post: use the files in a loop calling the extracting script.

WOW!! You're being a huge help.

To answer your question: Yes, all of the zone files are kept in a directory called /var/named/ . And all of the zone files has the file extension .db .

So how could I run your second script so that it pretty much looks for all the zone files inside /var/named/ (or any other directory for that matter), and replace any VirtualHost IP in httpd.conf, that does not match the ip with the zone file?

We're getting close! (Well, YOU are getting close would be the correct term. )

[J65nko]

To produce output to stdout

for FILE in /var/named/*db ; do ./extract  $FILE ; done

To get it into a file 'all-records.txt':

for FILE in /var/named/*db ; do ./extract  $FILE ; done >all-records.txt

You can filter out the ftp and localhost entries by using grep

./extract zone-example | egrep -v '(^localhost|^ftp)'
accounttest.com. IN A 35.45.68.21

Cannot you just regenerate those virtual hosts sections like I did in the first script?

[J65nko]

Separate the virtual hosts sections from the main httpd.conf. Put all of them in a single file. Use the "Include" directive to include this virtualhost-only configuration file into the main httpd.conf.

There are two possibilities:

1. The virtual hosts configurations are identical
   
   In this case you could just regenerate them using my first script.
   In that script I used a simplified <VirtualHost> section. You will have to adapt the first script to generate an exact clone of your <VirtualHost> directives.
   
2. The virtual host entries are not identical
   
   In this case, updating the IP address is the best solution.
   This has the disadvantage that the script will be more complex. You will need to ask somebody proficient in and scripting language like Perl, Python or Ruby to write it for you.

BTW a possible simpler way would be to scan for the virtual host names and use dig to resolve the name to the IP address[/b].
A couple of ServerName entries to test:

$ grep ServerName virtual-sample  
    ServerName accounttest.com
    ServerName gorilla.org
    ServerName monkey.org

A simple shell script

#!/bin/sh
FILE=virtual-sample

ALL=$( sed -ne 's/^[[:blank:]]*ServerName  *//p' ${FILE} )

for Host in ${ALL} ; do
   echo "${Host}=$(dig +short -t A ${Host})"
done

A sample run

$ sh dig-them        
accounttest.com=
gorilla.org=128.121.215.221
monkey.org=152.160.49.201

By redirecting the output to file you have a list of all the virtual hosts and their IP addresses, which can be used in either approach 1 or 2 as outlined above.

[bigb89]

Sorry for the late reply J65nko.

Once again, I thank you for the help you've been giving me.

To answer you question: No, I can't just generate the VirtualHost. I need to scan httpd.conf and replace the IP. Like you said, I'll prob have to find someone to help me out with that part.

[J65nko]

I actually started working on the script in Perl, although my Perl skills have become a little bit rusty

I already can read in VirtualHost section and store it in an array, ready to be processed.

[bigb89]

Originally Posted by J65nko

I actually started working on the script in Perl, although my Perl skills have become a little bit rusty

I already can read in VirtualHost section and store it in an array, ready to be processed.

That's nice to hear.

If you're able to come up with such script that would save me a lot of time hehehehe.

I understand that you've doing this totally out of your freewill so I'm thankful for the help you have given me.

[J65nko]

I have a working script. A snippet from the current output

Storing: <VirtualHost 11.22.33.44:80>
Storing:     ServerName accounttest.com
Storing:     ServerAlias www.accounttest.com
Storing: </VirtualHost>
Processing:     ServerName accounttest.com  | (Extracted  domain name = [accounttest.com] )
No IP address known for accounttest.com

                 Following section rejected
--<VirtualHost 11.22.33.44:80>
--    ServerName accounttest.com
--    ServerAlias www.accounttest.com
--</VirtualHost>
===
===# a remark
Storing: <VirtualHost 111.222.333.444:80>
Storing:     ServerName gorilla.org
Storing:     ServerAlias www.gorilla.org
Storing: </VirtualHost>
Processing:     ServerName gorilla.org  | (Extracted  domain name = [gorilla.org] )
Processing: <VirtualHost 111.222.333.444:80> ( Extracted IP number:  111.222.333.444 ) Port number = :80 
Changing 111.222.333.444 -> 128.121.215.221
Result: <VirtualHost 128.121.215.221:80>

So it still needs some cleanup

[bigb89]

Nice!

I can't wait to test it and see how it works out.

[J65nko]

This is what I have now. Not completely as I want it, but didn't want to have you wait any longer

This is the sample virtual hosts configuration file I used:

$cat virt_orig.txt           
# start of virtual hosts
<VirtualHost 11.11.11.11:80>
    ServerName kpn.com
    ServerAlias www.kpn.com
</VirtualHost>

# a remark preceded by an empty line
<VirtualHost 22.22.22.22:80>
    # ServerName fish.org 
    ServerName gorilla.org
    ServerAlias www.gorilla.org
</VirtualHost>
# another remark followed by an empty line

<VirtualHost 33.33.33.33:8080>
    # --- home of the monkeys
    ServerName monkey.org
    ServerAlias www.monkey.org
    ServerAdmin webmaster@monkey.org
</VirtualHost>

<VirtualHost 4.4.4.4:8080>
    #
    # Our forum
    # 
    ServerName daemonforums.org
    ServerAlias www.daemonforum.org
    ServerAdmin webmaster@monkey.org
</VirtualHost>

You first run the dig-them script (see my previous posts) to extract the servernames and lookup the corresponding IP address

$ ./dig-them virt_orig.txt                
kpn.com=145.7.192.133
gorilla.org=128.121.215.221
monkey.org=152.160.49.201
daemonforums.org=67.205.67.40

This produces the current domain -> IP address mappings.

The perl script, I called it 'virt-update', will read a file called 'domain-addr.txt' and expects this format. To create this file

$ ./dig-them virt_orig.txt >domain-addr.txt

The name 'domain-addr.txt' is still hard-coded in the 'virt-update' perl script, but that could be changed

Now you can run the following perl script:

#!/usr/bin/perl -w

# $Id: virt-update,v 1.4 2008/11/24 01:47:17 j65nko Exp $ 

#  Copyright (c) 2008 J65nko <Administrator daemonforums.org>
# 
#  Permission to use, copy, modify, and/or distribute this software for any
#  purpose with or without fee is hereby granted, provided that the above
#  copyright notice and this permission notice appear in all copies.
# 
#  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
#  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
#  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
#  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
#  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
#  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
#  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
# 

use strict ;

my @section ;  # <VirtualHost> ... </VirtualHost> section
my %address ;  # hash with  domain -> IP mappings 
my $debug ;

sub parse ;
sub process_section ;
sub show ;
sub get_ServerName ;
sub write_section ;
sub write_rejects ;

sub parse {
    my $i = -1 ; # first element of array is array[0], and we use ++$i
    while (<>) {
    	if ( /^\s*<VirtualHost/ .. /^\s*<\/VirtualHost>/ ) {
	    $section[++$i] = $_ ; # store line in array @section
	    #print  "Storing: $_" ;
            if ( /^\s*<\/VirtualHost>/ ) { # complete section stored? 
            	process_section ; 
	        $#section = 0 ; # empty @section array 
		$i = -1 ;       # init index	
            }
	next ;
	}
	#print   "\nPassing through unprocessed: $_" ;
	print RESULT ; # simply pass through non-section lines 
    } # end while
} # end sub

sub process_section {
    my $domain ;
    my $ip ;
    my $port ; 
    
    $domain = get_ServerName ; # scan @section for Servername
    if ( $domain eq "" ) { die 'Panic: No ServerName directive' ; }
    # we didn't die so there is life after a Servername ...
    print " (Extracted  domain name = [$domain] )" ; 
    if ( not exists $address{$domain} ) { # domain -> addr mapping?
       print  "\nNo IP address known for $domain\n" .
	     "Following section rejected" ;
       show ;
       unshift @section, "# NOT UPDATED because of unresolvable domain name\n" ;
       write_rejects ; # write section to rejected file
       write_section ; # but still write to output file
       return ;
    }

    # $section[0] is  first element of opening '<Virtualhost 1.2.3.4:80>'
    if ( $section[0] =~ m/^\s*<VirtualHost\s+(\d+\.\d+\.\d+.\d+)(:\d+)?\s*>/ ) {
        $ip = $1 ;
        $port = $2 ;
        if ( $debug == 1 ) { 
	    print  "\nProcessing: $section[0]" ; 
	    print " ( Extracted IP number:  $ip )" ;
	    print " Port number = $port " ;
	}
 
        if ( $ip eq $address{$domain} ) {
            if ( $debug == 1 ) {
		print  "\n======= No change for $domain at $ip ======" ;
		#show ;
		#print  "\n======= end of unchanged section ==========" ;
	        }	
            write_section ;
	    return ;
        }
        else {
            print  "\nChanging $ip -> $address{$domain}" ;
            $section[0] =~ s/\d+\.\d+\.\d+\.\d+(:\d+)?/$address{$domain}$port/ ;
	    print  "\nResult: $section[0]" ;
	    write_section ;
        }
     
    } else { die "Panic: Aborting processing ... No <VirtualHost> entry found!" ; }  
} # end sub process_section

# scan @section array for ServerName directive
sub get_ServerName {
    if ( $debug == 1 ) { print "\nScanning section for ServerName\n" ; }
    for (@section) {
        print "$_" ;
	if ( /^\s*ServerName\s+(\S+)$/ ) {
	    if ($debug == 1 ) { print  "Processing : $_" ; } 
            return $1 ;
	}
    }
}

# --- read  "domain -> IPaddr" mappings file and store in hash table %address
sub get_mapping {
    my ($domain, $ip ) ;
    my $file = 'domain-addr.txt' ;
    open ( FILE, "< $file" ) or die "Cannot open $file"  ; 
    while ( <FILE> ) {
        chomp ; # get rid of LF
        ($domain, $ip) = split /=/ ;
        #print   "\nDomain: [$domain] IP: [$ip]" ;
        if ( $ip eq "" ) {
            print  "\nDomain $domain has no IP address. Skipping $domain ..." ; 
        next ;
        }
    $address{$domain} = $ip ;
    }
}

sub show {
   for  (@section) {
        print "\n--$_" ;
   }
}

sub write_section {
    for (@section) {
	print RESULT ; # print implied $_
    } 
}

sub write_rejects {
    for (@section) {
	print REJECT ; # print implied $_
    } 
}

# --- main
get_mapping ;	# read file 'domain-addr.txt' into %address hash

open ( RESULT, "> virt_updated.txt" ) or die "Cannot open updated.txt!" ;
open ( REJECT, "> virt_rejects.txt" ) or die "Cannot open updated.txt!" ;

# output  (only to see synchronized debugging messages)
$debug = 1 ;

if ( $debug == 1 ) { 
    $| = 1 ; # enable autoflush for synced debugging stuff 
} 

parse ;

print <<EOF ;

---- Message
Updated file : virt_updated.txt
A copy of unmodified sections because of unknown IP address : virt_rejects.txt

To see the differences run    
   
    diff -u name_of_original_file  virt_updated.txt

--- End of message
EOF

END { close RESULT ; close REJECT ; }

You have to tell it, which virtual host config file to use. It will not modify this file at all. It will produce a modified version in the file "virt-updated.txt'.
The domains for which the 'domain-addr.txt' has found no IP address, the virtual hosts sections will be copied to the file "virt-updated.txt'.
An extra copy will be written to the file 'virt_rejects.txt'.

So here we go:

$ ./virt-update virt_orig.txt

The debugging code will show this for the last section

Scanning section for ServerName
<VirtualHost 4.4.4.4:8080>
    #
    # Our forum
    # 
    ServerName daemonforums.org
Processing :     ServerName daemonforums.org
 (Extracted  domain name = [daemonforums.org] )
Processing: <VirtualHost 4.4.4.4:8080>
 ( Extracted IP number:  4.4.4.4 ) Port number = :8080 
Changing 4.4.4.4 -> 67.205.67.40
Result: <VirtualHost 67.205.67.40:8080>

To see the changes you can run diff to compare the new file with the original

$ diff -u virt_orig.txt virt_updated.txt
--- virt_orig.txt       Mon Nov 24 02:41:22 2008
+++ virt_updated.txt    Mon Nov 24 03:19:52 2008
@@ -1,25 +1,25 @@
 # start of virtual hosts
-<VirtualHost 11.11.11.11:80>
+<VirtualHost 145.7.192.133:80>
     ServerName kpn.com
     ServerAlias www.kpn.com
 </VirtualHost>
 
 # a remark preceded by an empty line
-<VirtualHost 22.22.22.22:80>
+<VirtualHost 128.121.215.221:80>
     # ServerName fish.org 
     ServerName gorilla.org
     ServerAlias www.gorilla.org
 </VirtualHost>
 # another remark followed by an empty line
 
-<VirtualHost 33.33.33.33:8080>
+<VirtualHost 152.160.49.201:8080>
     # --- home of the monkeys
     ServerName monkey.org
     ServerAlias www.monkey.org
     ServerAdmin webmaster@monkey.org
 </VirtualHost>
 
-<VirtualHost 4.4.4.4:8080>
+<VirtualHost 67.205.67.40:8080>
     #
     # Our forum
     #

In this case there were no rejects

$ ls -l virt*txt 
-rw-r--r--  1 j65nko  j65nko  680 Nov 24 02:41 virt_orig.txt
-rw-r--r--  1 j65nko  j65nko    0 Nov 24 03:19 virt_rejects.txt
-rw-r--r--  1 j65nko  j65nko  694 Nov 24 03:19 virt_updated.txt

To uncompress the attached file

$ tar xvzf virt-updater.tgz

[bigb89]

Hi J65nko,

I really appreciate all the help you've given me.

Sorry for the late reply, I've been really busy with alot of stuff.

Anyways, I'm gonna test your script and I'll let you know how it goes.

[J65nko]

As an alternative for the "dig-then" sh script, I wrote a Perl script that does the same thing.

$cat select-domains

#!/usr/bin/perl -w

# $Id: select-domains,v 1.3 2008/11/27 01:35:49 j65nko Exp $

#  Copyright (c) 2008 J65nko <Administrator daemonforums.org>
# 
#  Permission to use, copy, modify, and/or distribute this software for any
#  purpose with or without fee is hereby granted, provided that the above
#  copyright notice and this permission notice appear in all copies.
# 
#  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
#  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
#  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
#  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
#  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
#  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
#  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
# 

use strict ;

my $filename = "domain-addr.txt" ; 
my @domains ;
my $IP ;

# scan VirtualHost input file for ServerName entries, extract the domain name
# and store in array '@domains'

print "\n$0: Scanning domain names ....\n" ;

while (<>) {
    if ( /^\s*<VirtualHost/ .. /^\s*<\/VirtualHost>/ ) {
        if ( /^\s*ServerName\s+(\S+)$/ ) {
            print "\nDomain: $1" ;
            push @domains,$1
        }
    }
}

open ( FILE, "> $filename" ) or die "Cannot open $filename !" ;

print  "\n\n$0: Starting to resolve domains....\n" ;

# for every domain in array, use 'dig' to lookup IP address

for ( @domains ) {
    print "\nResolving: $_ " ;
    $IP = '' ;
    $IP = `dig +short -t A $_` ; # Use 'dig' to resolve domain
    print FILE "$_=" ;
    if ( $IP =~ m/^(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}).*/ ) {
        $IP =  $1 ;
        chomp $IP ;
        print "  IP: $IP" ;
        print FILE "$IP\n" ;
    } else {
         print " IP: Not resolved" ; 
         print FILE "\n" ;
    }
} 

print "\n\n$0: Finished!\n" ;

END {
close (FILE) or print "Couldn't close file: $filename"  ;
}
# --- end of program

The advantage is that it logs information to stdout, what it is actually doing.
A sample run, where again 'virt_orig.txt" is the VirtualHost configuration file

$ select-domains virt_orig.txt | tee logfile 

./select-domains: Scanning domain names ....

Domain: google.com
Domain: ixcdgorilla.org
Domain: monkey.org
Domain: daemonforums.org

./select-domains: Starting to resolve domains....

Resolving: google.com   IP: 209.85.171.100
Resolving: ixcdgorilla.org  IP: Not resolved
Resolving: monkey.org   IP: 152.160.49.201
Resolving: daemonforums.org   IP: 67.205.67.40

./select-domains: Finished!

By using the "tee" program, the logged messages to the screen, are also saved in the file 'logfile".
The actual results are in the file "domain-addr.txt":

$ cat  domain-addr.txt
  
google.com=209.85.171.100
ixcdgorilla.org=
monkey.org=152.160.49.201
daemonforums.org=67.205.67.40

[bigb89]

Wow J65nko!!

You have done more than if I was paying programmer to create that script. LOL

Thank you once again for help.

P.S. Once I get my programming skills up, I plan on helping the community just like you have helped me.

[J65nko]

Thanks for the kind words.

I found the problem interesting, and thought it was a nice opportunity to polish up my rusty Perl scripting skills