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Changing NAT rules on a cisco pix

Hello

I need to change the configuration on a cisco pix to forward traffic to a new server that has been installed (e.g. current ports are forwarded from External IP -> 192.168.0.1 , new Port forwarding must be external IP -> 192.168.0.2 )

I also want to change the standard port for RDP from 3389 to something else (4300 for example) so that the port the RDP client uses is different (e.g. remote.example.com.au:4300)

We are also changing the internal domain name from "example.local" to "example2.local"
The server name will also be changing from "exampleserver" to "exampleserver2"

Lastly being that the new server is a SBS 2011 server, the other following port must be forwarded: 443, 987, 1723

Please see a snippet of the configuration below:

***************************************
PIX Version 6.3(3)
interface ethernet0 100full
interface ethernet1 100full
nameif ethernet0 outside security0
nameif ethernet1 inside security100
enable password 0e53SZdxezxawxDG encrypted
passwd 0e53SZdxezxawxDG encrypted
hostname example-fw
domain-name example.local
fixup protocol dns maximum-length 512
fixup protocol ftp 21
fixup protocol h323 h225 1720
fixup protocol h323 ras 1718-1719
fixup protocol http 80
fixup protocol pptp 1723
fixup protocol rsh 514
fixup protocol rtsp 554
fixup protocol sip 5060
fixup protocol sip udp 5060
fixup protocol skinny 2000
no fixup protocol smtp 25
fixup protocol sqlnet 1521
fixup protocol tftp 69
names
name 192.168.0.1 EXAMPLESERVER
access-list outside_access_in permit tcp any interface outside eq smtp
access-list outside_access_in permit tcp any interface outside eq pptp
access-list outside_access_in permit tcp any interface outside eq 3389
access-list outside_access_in permit gre any interface outside
access-list outside_access_in permit icmp any interface outside echo-reply
access-list outside_access_in permit icmp any interface outside time-exceeded
access-list outside_access_in permit icmp any interface outside unreachable
access-list outside_access_in permit icmp any interface outside source-quench
access-list outside_access_in permit tcp any interface outside eq www
access-list outside_access_in permit tcp any interface outside eq https
pager lines 24
mtu outside 1492
mtu inside 1500
ip address outside 112.235.128.99 255.255.255.0
ip address inside 192.168.0.254 255.255.255.0
ip audit info action alarm
ip audit attack action alarm
pdm location 192.168.0.0 255.255.255.0 inside
pdm history enable
arp timeout 14400
global (outside) 1 interface
nat (inside) 1 0.0.0.0 0.0.0.0 0 0
static (inside,outside) tcp interface smtp SERVER smtp netmask 255.255.255.255 0
 0
static (inside,outside) tcp interface pptp SERVER pptp netmask 255.255.255.255 0
 0
static (inside,outside) tcp interface 3389 SERVER 3389 netmask 255.255.255.255 0
 0
static (inside,outside) tcp interface www SERVER www netmask 255.255.255.255 0 0

static (inside,outside) tcp interface https SERVER https netmask 255.255.255.255
 0 0
access-group outside_access_in in interface outside
conduit permit gre host EXAMPLESERVER any
route outside 0.0.0.0 0.0.0.0 112.235.128.254 1
timeout xlate 3:00:00
timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 rpc 0:10:00 h225 1:00:00
timeout h323 0:05:00 mgcp 0:05:00 sip 0:30:00 sip_media 0:02:00
timeout uauth 0:05:00 absolute
aaa-server TACACS+ protocol tacacs+
aaa-server RADIUS protocol radius
aaa-server LOCAL protocol local
http 192.168.0.0 255.255.255.0 inside
no snmp-server location
no snmp-server contact
snmp-server community public
no snmp-server enable traps
floodguard enable
vpngroup CiscoClient dns-server 112.235.130.1 112.235.130.2
vpngroup CiscoClient idle-time 1800
telnet 192.168.0.0 255.255.255.0 inside
telnet timeout 5
ssh 192.168.0.0 255.255.255.0 inside
ssh timeout 5
console timeout 0
dhcpd dns 112.235.130.1 112.235.130.2
terminal width 80
END
************************************

I also have a feeling there is a heap of other lines of config which aren't required, if you could also give me a heads up on those it would be appreciated

Regards


KYMD
0
kymd26
Asked:
kymd26
  • 4
2 Solutions
 
Ernie BeekCommented:
So the new statics would be:

static (inside,outside) tcp interface smtp 192.168.0.2 smtp netmask 255.255.255.255 0 0
static (inside,outside) tcp interface pptp 192.168.0.2 pptp netmask 255.255.255.255 0 0
static (inside,outside) tcp interface 4300 192.168.0.2 3389 netmask 255.255.255.255 0 0
static (inside,outside) tcp interface www 192.168.0.2 www netmask 255.255.255.255 0 0
static (inside,outside) tcp interface https 192.168.0.2 https netmask 255.255.255.255 0 0


I also added the outside port 4300 for RDP. If everything is working you then can remove the old statics.

You'll need to change:
access-list outside_access_in permit tcp any interface outside eq 3389
to
access-list outside_access_in permit tcp any interface outside eq 4300

to be able to access RDP on the new port.
0
 
Ernie BeekCommented:
Oh, and the new ports:

You'll need:

static (inside,outside) tcp interface 789 192.168.0.2 789 netmask 255.255.255.255 0 0
static (inside,outside) tcp interface 1723 192.168.0.2 1723 netmask 255.255.255.255 0 0


And

access-list outside_access_in permit tcp any interface outside eq 789
access-list outside_access_in permit tcp any interface outside eq 1723


https (443) is already there

For the new name, just add:

name 192.168.0.2 EXAMPLESERVER2
0
 
Ernie BeekCommented:
With regards to the rest of the config, I don't see any unnecessary stuff (just default things mostly). Anything in particular you're doubting about?
0
 
kymd26Author Commented:
Thanks for the info / commands

Just wondering, if I add all the new Statics as mentioned in the first comment, won't there be some confusion to where the traffic goes (e.g. Traffic coming in on port 25 would have 2 x statics configured (to both .1 and .2), wouldn't I need to remove the original statics before the new ones would work?

Regards

KYMD
0
 
Ernie BeekCommented:
Argh! Need more coffee :(

I stand corrected, you are completely right. You can't add the new ones before removing the old ones.
The ASA would have told you so though.

If you would excuse me, I'm first going to get a coffee infusion ;)
0

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