DrayTek UK Users' Community Forum
Help, Advice and Solutions from DrayTek Users
Restricting SMTP traffic
- simon@npit.co.uk
- Topic Author
- Offline
- New Member
-
Less
More
- Posts: 2
- Thank you received: 0
28 Jul 2009 09:51 #1
by simon@npit.co.uk
Restricting SMTP traffic was created by simon@npit.co.uk
I have a vigor router 2820, i am trying to block all the incoming traffic on port 25 from any ip address and enable it only from one ip address to avoid receiving spam. i have created data rules but still not able to block the traffic from Public. i was testing by blocking all the SMTP traffic, by setting a rule to block any traffic on port 25, i have enabled that rule but still able to receive emails. Please advise. by the way how can i attach a snapshot?
Please Log in or Create an account to join the conversation.
- simon@npit.co.uk
- Topic Author
- Offline
- New Member
-
Less
More
- Posts: 2
- Thank you received: 0
28 Jul 2009 15:19 #2
by simon@npit.co.uk
Replied by simon@npit.co.uk on topic Re: Restricting SMTP traffic
I have a vigor router 2820, i am trying to block all the incoming traffic on port 25 from any ip address and enable it only from one ip address to avoid receiving spam. i have created data rules but still not able to block the traffic from Public. i was testing by blocking all the SMTP traffic, by setting a rule to block any traffic on port 25, i have enabled that rule but still able to receive emails. Please advise. by the way how can i attach a snapshot?simon@npit.co.uk wrote:
Please Log in or Create an account to join the conversation.
- eriqlasale
- Offline
- New Member
-
Less
More
- Posts: 3
- Thank you received: 0
18 Aug 2009 11:43 #3
by eriqlasale
Replied by eriqlasale on topic Blocking incoming traffic on port 25
Hi Simon
I can't answer your question but maybe you could help me?!?!?!?
I need to block all incoming traffic on port 25 - I keep ending up listed in xbl! I have no idea how to do this - I have set up a filter rule but don't know if I have done it correctly - could you explain how you did it for me - or send me a screen shot or something?
Regards........Eric
I can't answer your question but maybe you could help me?!?!?!?
I need to block all incoming traffic on port 25 - I keep ending up listed in xbl! I have no idea how to do this - I have set up a filter rule but don't know if I have done it correctly - could you explain how you did it for me - or send me a screen shot or something?
Regards........Eric
Please Log in or Create an account to join the conversation.
- mordorf
- Offline
- Junior Member
-
Less
More
- Posts: 84
- Thank you received: 0
18 Aug 2009 19:38 #4
by mordorf
Replied by mordorf on topic Restricting SMTP traffic
This is the way I'd do it. It's a bit belt and braces. Really you should only need the ALLOW IN SMTP part as most firewalls should add a DENY ALL rule at the end. But some people do strange things with firewalls, this way should hopefully take some of that into account. It's important to understand that most firewalls work as a list that is read from top to bottom, the first full rule match will be the one that takes effect.
eriqlasale, I'd say you are getting listed on a spammers database either because your email server is an open relay, in which case you really need to sort this out or you have an infected computer that is acting as a spammers mail server, in which case I'd block outbound SMTP connections, find the infected computer and get it cleaned up.
To block outbound SMTP change the DIRECTION to LAN>WAN.
1.)Create a new rule called something like BLOCK IN SMTP
2.)Set DIRECTION to WAN>LAN
3.)Set SOURCE IP to ANY
4.)Set DESTINATION IP to ANY
5.)SERVICE TYPE:
SERVICE TYPE - USER DEFINED
PROTOCOL – TCP
SOURCE PORT – 1~65535
DESTINATION PORT – 25~25
6.) Set ACTION/PROFILE to BLOCK IF NO FURTHER MATCH
1.)Create another new rule called something like ALLOW IN SMTP
2.)Set DIRECTION to WAN>LAN
3.)Set SOURCE IP to the IP Address you require
4.)Set DESTINATION IP to the internal IP Address of your SMTP Server
5.)SERVICE TYPE:
SERVICE TYPE - USER DEFINED
PROTOCOL – TCP
SOURCE PORT – 1~65535
DESTINATION PORT – 25~25
6.) Set ACTION/PROFILE to PASS IMMEDIATELY
Hope this helps.
eriqlasale, I'd say you are getting listed on a spammers database either because your email server is an open relay, in which case you really need to sort this out or you have an infected computer that is acting as a spammers mail server, in which case I'd block outbound SMTP connections, find the infected computer and get it cleaned up.
To block outbound SMTP change the DIRECTION to LAN>WAN.
1.)Create a new rule called something like BLOCK IN SMTP
2.)Set DIRECTION to WAN>LAN
3.)Set SOURCE IP to ANY
4.)Set DESTINATION IP to ANY
5.)SERVICE TYPE:
SERVICE TYPE - USER DEFINED
PROTOCOL – TCP
SOURCE PORT – 1~65535
DESTINATION PORT – 25~25
6.) Set ACTION/PROFILE to BLOCK IF NO FURTHER MATCH
1.)Create another new rule called something like ALLOW IN SMTP
2.)Set DIRECTION to WAN>LAN
3.)Set SOURCE IP to the IP Address you require
4.)Set DESTINATION IP to the internal IP Address of your SMTP Server
5.)SERVICE TYPE:
SERVICE TYPE - USER DEFINED
PROTOCOL – TCP
SOURCE PORT – 1~65535
DESTINATION PORT – 25~25
6.) Set ACTION/PROFILE to PASS IMMEDIATELY
Hope this helps.
Please Log in or Create an account to join the conversation.
- eriqlasale
- Offline
- New Member
-
Less
More
- Posts: 3
- Thank you received: 0
21 Aug 2009 11:57 #5
by eriqlasale
Replied by eriqlasale on topic Restricting SMTP traffic
Hi Mordorf
Thank you very much for this - extremely helpful.
My mail server is external to the network though - it is hosted with heart internet so I don't think I have to worry about that. I am going to block port 25 completely and see what happens - hopefully it will fix it.
Thanks again for your help - restores one's belief in the kindness of others!
Thank you very much for this - extremely helpful.
My mail server is external to the network though - it is hosted with heart internet so I don't think I have to worry about that. I am going to block port 25 completely and see what happens - hopefully it will fix it.
Thanks again for your help - restores one's belief in the kindness of others!
Please Log in or Create an account to join the conversation.
- paul_hood
- Offline
- Junior Member
-
Less
More
- Posts: 18
- Thank you received: 0
28 Aug 2009 18:53 #6
by paul_hood
Replied by paul_hood on topic Restricting SMTP traffic
Hi,
I have just tried to follow this gude to block unwanted SMTP traffic from our network to the internet (AKA in case of a virus).
Following the instructions other than changing the direction to "LAN>WAN" what else needs to be done as it dosent work/take effect![:( :(](/media/kunena/emoticons/18.png)
I have just tried to follow this gude to block unwanted SMTP traffic from our network to the internet (AKA in case of a virus).
Following the instructions other than changing the direction to "LAN>WAN" what else needs to be done as it dosent work/take effect
![:( :(](/media/kunena/emoticons/18.png)
Please Log in or Create an account to join the conversation.
Moderators: Sami
Copyright © 2024 DrayTek