Title: SMTP access list
I think you need to have the 3rd line because if you do not, then all other traffic will be denied.
Elmer,
 
The router applies the first match and neglects the remaining lines.
i.e. in your example, only any traffic from the 3 mentioned sources & carrying smtp will be allowed. Note that the last 2 lines are unnecessary, as the implicit deny any will apply in all cases.
To make it clearer, suppose we have something like:
access-list 176 permit tcp 193.128.233.177 0.0.0.0 any eq smtp log
access-list 176 deny tcp 193.128.233.177 0.0.0.0 any eq smtp
access-list 176 permit ip any any
 
The smtp traffic from the mentioned host will be permitted although it's denied in the second line.
 
I hope this helps.
 
Regards,
Shahir Boshra
Telecommunications Specialist
USAID - Egypt

 
""Deloso, Elmer G."" <[EMAIL PROTECTED]> wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]...

Hi, all.
Just to verify my understanding of extended access-lists: this continues to parse the entries even
after a match has already been found, so if the first few lines have a "permit" and later down the last few lines it encounters a "deny", what does the router do?

Example:
access-list 176 permit tcp 193.128.233.177 0.0.0.0 any eq smtp log
access-list 176 permit tcp 203.23.83.180 0.0.0.0 any eq smtp log
access-list 176 permit tcp 203.35.182.133 0.0.0.0 any eq smtp log
.
.
.
.
access-list 176 deny ip 193.0.0.0 0.255.255.255 any log
access-list 176 deny ip 203.0.0.0 0.255.255.255 any log

Any help would be greatly appreciated.

Elmer Deloso

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