Digital Library Of Linux

SSHFS is a tool that uses SSH to enable mounting of a remote filesystem on a local machine. This tool can be used for directories sharing. SSHFS is built using FUSE and non-priviliged users can create their own file systems. Only two steps needed to use sshfs.

1) Install sshfs
2) Edit /etc/group and add your login name in the FUSE group

How to share a directory using sshfs

1) Create a local directory for the mountpoint.
mkdir /home/user/TEST
2) Mount any directory from the remote machine
sshfs foo@remote_machine:/home/foo home/user/TEST

Now the directory 'TEST' has all the contents of the remote home directory of foo.
The files in this directory are editable and can move around just as though it were a
local directory.

Here is a simple perl script that i found to delete my mails in postqueue.

1) Create a file (eg:delete_queue.pl) and paste the scripts below
2) chmod a+x delete_queue.pl
3) ./delete_queue.pl "mail id" (Delete mail based on mail id)
4) ./delete_queue.p "email address" (Delete mails from the same email address)

#!/usr/bin/perl -w
#
# pfdel - deletes message containing specified address from
# Postfix queue. Matches either sender or recipient address.
#
# Usage: pfdel 
#

use strict;

# Change these paths if necessary.
my $LISTQ = "/usr/sbin/postqueue -p";
my $POSTSUPER = "/usr/sbin/postsuper";

my $email_addr = "";
my $qid = "";
my $euid = $>;

if ( @ARGV !=  1 ) {
die "Usage: pfdel \n";
} else {
$email_addr = $ARGV[0];
}

if ( $euid != 0 ) {
die "You must be root to delete queue files.\n";
}


open(QUEUE, "$LISTQ |") ||
die "Can't get pipe to $LISTQ: $!\n";

my $entry = ; # skip single header line
$/ = "";  # Rest of queue entries print on
# multiple lines.
while ( $entry =  ) {
if ( $entry =~ / $email_addr$/m ) {
($qid) = split(/\s+/, $entry, 2);
$qid =~ s/[\*\!]//;
next unless ($qid);

#
# Execute postsuper -d with the queue id.
# postsuper provides feedback when it deletes
# messages. Let its output go through.
#
if ( system($POSTSUPER, "-d", $qid) != 0 ) {
# If postsuper has a problem, bail.
die "Error executing $POSTSUPER: error " .
   "code " .  ($?/256) . "\n";
}
}
}
close(QUEUE);

if (! $qid ) {
die "No messages with the address <$email_addr> " .
"found in queue.\n";
}

exit 0;

How to configure postfix to filter mail attachments based on file extension? This was one of the question has been lurking in my mind for past few days. Finally i got the solution from my fren "google". Its can be done by 3 simple steps as follow

1) Edit main.cf and add this line > mime_header_checks = regexp:/etc/postfix/mime_header_checks
2) Edit mime_header_checks file and add /name=[^>]*\.(bat|com|exe|dll|vbs|jpg)/ REJECT
It means that, all the file extension listed will be rejected during file attachment.You can add more file extensions by adding this line with |.
3) Postmap mime_header_checks

You are done. Now try to attach the rejected file extension and you will see a pop up message on attachment filtering.