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outside source deny all but few ports

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lebisol

IS-IT--Management
Jan 3, 2003
3,325
US
Hello everyone.
I need little help with ACLs....not a cisco guru so don't laugh at my request. :)
So far I have natted out the paths I need I am just looking to lock down all the 'unused ports' including pings and echos and any reponse other than 2 ports used.
Code:
...
ip nat inside source static tcp 192.168.1.15 443 my.wan.ip.here 443 extendable
ip nat inside source static tcp 192.168.1.15 25 my.wan.ip.here 25 extendable
ip nat outside source static 192.168.1.15 my.wan.ip.here extendable
...
I am using 'outside source' since WAN IP is one of my secondary IPs and want the server to reflect it vs. gefault gateway.
Looking to lock down everything and allow ONLY SSL and SMTP as you can tell.
Many thanks for your time!

:--------------------------------------:
fugitive.gif


All around in my home town,
They tryin' to track me down...
 
You are correct, mail servers use a random high port to send mail and receive mail on port 25. However, that ACL does not block any outbound traffic.
 
yeah rather strange...as you can tell loosing sleep over it.
ALC is set to be IN but for some reson the moment it is applied the SMTP queue gets crammed. I clear the ACL and back in action.
Seems like rather than using
"access-list 101 deny ip any host xxx.xxx.xxx.200"
it would be better to just manually block port ranges...not sure any more, I have no hair left. :)
Thanks guys!

:--------------------------------------:
fugitive.gif


All around in my home town,
They tryin' to track me down...
 
its right above:
Code:
interface FastEthernet0/0
 description LAN Interface
 ip address 192.168.1.2 255.255.255.0
---
interface FastEthernet0/1
 description WAN Interface
 ip address xxx.xxx.xxx.195 255.255.255.240 secondary
 ip address xxx.xxx.xxx.196 255.255.255.240 secondary
 ip address xxx.xxx.xxx.197 255.255.255.240 secondary
 ip address xxx.xxx.xxx.198 255.255.255.240 secondary
 ip address xxx.xxx.xxx.194 255.255.255.240
---
ip route 0.0.0.0 0.0.0.0 xxx.xxx.xxx.193
---
ip nat inside source list 100 interface FastEthernet0/1 overload
ip nat inside source static 192.168.1.15 xxx.xxx.xxx.200 extendable
---
access-list 100 permit ip 192.168.1.0 0.0.0.255 any
access-list 101 permit tcp any host xxx.xxx.xxx.200 eq 443
access-list 101 permit tcp any host xxx.xxx.xxx.200 eq smtp
access-list 101 deny   ip any host xxx.xxx.xxx.200 
access-list 101 permit ip any any

applied on FE0/1
Thanks!

:--------------------------------------:
fugitive.gif


All around in my home town,
They tryin' to track me down...
 
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