limit inbound mail size for specific email user

[supun1989]

I know we can min and max inbound/outbound mail as per the listener. But Is there any possibility of max/min email size for specific email account?

[pchakra2]

Hello,

Yes, you can achieve size limitation for specific users by creating a Content Filter and enabling the same in the Incoming/Outgoing Mail Policies. 

Incoming / Outgoing Content Filters --> Add Filter --> Add Condition --> Message Size --> Select option from dropdown (greater than or Less than or any other) --> Enter the value in Bytes --> Ok

Add Another condition --> Envelope Sender --> Select Equals from dropdown --> Enter the email address of the user --> Ok

From dropdown on top right of conditions tab ensure selecting "Only if All Conditions match".  ## This is very important step, don't miss that else filter will trigger unexpectedly ##

Add Action -> Quarantine or any other as per your choice --> Submit and commit the changes.

Next enable it in the desired Incoming / Outgoing Mail Policy.

Best Regards,

[pchakra2]

..

[marc.luescherFRE]

Another addition of that content filter would be the following :

a) create either a dictionary or a LDAP AD group like 5MB Limit, another one with 10MB etc.

b) modify the filter to check for recipient to be part of either the dictionary or the LDAP group. 

c) take action base don what you want to do. In order to use the NOT condition the filter needs to be implemented as a message filter on CLI. WHich might anyhow be a good idea as you will get a lot f hits on the lookup side.

Hope that helps.

-Marc

[Mathew Huynh]

Hey Supun,

Adding to Partha and Marc's comment...

Marc's workaround is quite interesting as well as it allows the management to be specific at the LDAP side (assuming you want to limit it based on your internal recipients assuming it's incoming traffic).

Partha's means gives you a way to manually create your list on the ESA itself but also allows to apply a limit based on sender.

There is one big caveat to both though - even if you create your message or content filter allowances, you will still be required to increase the inbound mail size limits on your Listener -> Mail Flow Policies. This means even if you want to restrict only certain senders to have large size and the rest having a smaller limit (or the other way around) you still need to ensure you up the size allowance on your mail flow policies before restrictions can be done.

(So ensure you also account for ~34% MIME inflation on mail sizes as well).

Regards,
Mathew