Recommened MSS Value Setting

Posted on 2009-07-05
Medium Priority
Last Modified: 2012-05-07
I would like to know the recommened MSS value settings in Cisco ASA 5510.
I am using Cisco ASA 5510 to connect to internet & NATing is enabled to it.

I am getting the following alerts in the Cisco ASA. Default MSS is configured in the Cisco ASA

%ASA-4-419001: Dropping TCP packet from outside: to inside:, reason: MSS exceeded, MSS 1380, data 1460

Would like to know what is the recommended MSS settings to be configured so that the packets are not rejected.

Question by:SrikantRajeev
  • 3
LVL 14

Expert Comment

ID: 24779256

Here's a Cisco document that explains the problem and has a workaround:


I'm checking a couple of other solutions.  I'll be back.
LVL 14

Expert Comment

ID: 24779266
And ..

I've been reading this:


and am wondering if the parameter needs to be adjusted in Windows?  

Check it out and see what you think?
LVL 14

Accepted Solution

uucknaaa earned 1500 total points
ID: 24779295

It looks like the recommended size is 1452.  There is an explanation in the usage guidelines for the command in this doc:


Hope this all helps the problem you are seeing.

Author Closing Comment

ID: 31599889

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