Ending Spam and Etc.


 
Thread Tools Search this Thread
Top Forums UNIX for Advanced & Expert Users Ending Spam and Etc.
# 1  
Old 01-17-2013
Ending Spam and Etc.

This is a very general question but the idea popped into my head several years ago and wanted the opinions of all the master jedi's of this forum. I had a client that no matter what was done to control there spam(spam assassin,anti-virus(email scanning) and etc) sooner or later something would slip through. So out of frustration of looking at different solution to the INTERNET that seem to be good control mechanisms for combating SPAM, nothing seems to severally reduce the problem without being to restrictive in which the customer may not receive much email at all. So I though, why not just allow email from the domains from there existing customers and block everything else. Simply query what they already have and block the rest. When a new client comes in just add it to a whitelist. To me this would eliminate most of the trash that is out there and lessen the chance of something slipping in but not 100% bullet proof. In addition to that still have your second defense barriers in place such as SPAMASSASSIN and an anti-virus email scanner in place for the domains that are allowed through. Also use SSL/TLS authentication(pretty standard) to protect credentials from being used to read email and or send SPAM through the account. Though this sounds really restrictive, it just seems more logical when it comes to protecting a business. So maybe using Sendmail, I would add this stuff under:

/etc/mail/access

1-Who we accept mail from
2-Who we accept relaying from
3-Who we will not send to etc

Sendmail blocking spam email id, ips with access database

Any feedback is greatly appreciated.

Last edited by metallica1973; 01-17-2013 at 12:45 PM..
# 2  
Old 01-17-2013
You can do this and it will probably reduce the load of SPAM you get somewhat. If you are looking for a 100%-solution, i have to bring bad news, though.

A certain sender in an email header is no guarantee that this specific person/system has sent the email. It is possible (in some situations even required) to rewrite header information in an email and thus, what begnign programs can do, malign programs can do too.

Second: there is - technically - no difference between SPAM and normal mail, which is why it is difficult to find a technical remedy that really works. All the email filters are working on a best-guess basis more or less and this ultimately means: some (many) times you guess right and some times you guess wrong.

Third: even if your solution really works, wouldn't the cure be more fatal than the disease? It is some distinct effort to create and maintain the whitelist. Is this effort smaller than to occasionally (your words) delete a mail you didn't want?

I hope this helps.

bakunin
# 3  
Old 01-24-2013
awesome. Many thanks
Login or Register to Ask a Question

Previous Thread | Next Thread

9 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

If loop not ending

Hi, The first if loop in the script not ending and going to infinite loop. #!/usr/bin/ksh set -vx lc=1 st_date=$(date "+%Y%m%d") LOGFILE=/home/infa_shared/OM_ftp_transfer.log.$st_date file="/home/infa_shared/OM_WF.log.$st_date" while ]; do if ] then sleep 15 let lc=lc+1 print... (4 Replies)
Discussion started by: nag_sathi
4 Replies

2. Shell Programming and Scripting

Nested for loop not ending

Hi All, Need help on below script for g in `cat /home/sid.txt` do for h in `cat /home/dev.txt` do symmaskdb -sid $g -dev $h list assign |grep FA |head -1|awk '{print $2}' > tt1.txt done done cat /home/sid.txt ************** 123 235 456 (5 Replies)
Discussion started by: ranjancom2000
5 Replies

3. SCO

File name ending with @

Hi Current SCO Unix 5.05 I see that there are filenames with @ at the end of file name for example in the /usr/lib there is file lpadmin@ what does the @ represent when it is at the end of the file name Thanks (4 Replies)
Discussion started by: atish0
4 Replies

4. Programming

numeric values ending in 'U'

I am getting back on the C++ programming after many years away. I recently received an SDK that has code like this where numeric values end in 'U'. What does this mean? if ((ptr % 16U) == 0U) return buffer; (3 Replies)
Discussion started by: sneakyimp
3 Replies

5. Shell Programming and Scripting

Ending a script

Hi all, I am trying to end a Menu script. Can people suggest various methods please? At the moment I am doing: quit=n while do ...Code Code Code... read userinput case $userinput in q|Q) quit=y;; esac done But this doesn't seem to work every time, occasionally it will work,... (6 Replies)
Discussion started by: mikejreading
6 Replies

6. Shell Programming and Scripting

never ending loop

Guys I have a script like the one below. One script executes another script in a loop. but i want the other script within the main script to be executed only 3 times. the script within the main script again references the main script after its execution. plz help. while } ] do... (21 Replies)
Discussion started by: ragha81
21 Replies

7. Programming

executables ending with *

Hi All, I m very new to unix. I have a basic doubt .. In unix I m seeing that there is a * at the end of by executable name (exe1*).. Wht is the significance of that Thanks a lot in advance (2 Replies)
Discussion started by: binums
2 Replies

8. UNIX for Dummies Questions & Answers

File- Ending

Hi folks! I'm new in this forum and in the UNIX-world too!! I've got a real problem: I have to read out datas like name and e-mail-adress from a Windows- Server from the active directory and put this information into a file. This file should be moved (or copied) on a Unix- Server... But I... (3 Replies)
Discussion started by: spikylina
3 Replies

9. UNIX for Dummies Questions & Answers

Ending Mail

hello, I a problem. I would like write script in True64 Unix.see below. last testerkl | head > mailfile.asc wolteru < mailfile.asc With the "last" command I get a list when testerkl logged on. And I would like to send this to a user. But how can I write in a "ctrl.-d" and "ctrl.-c" that... (2 Replies)
Discussion started by: Peterh
2 Replies
Login or Register to Ask a Question