Exchange server setup behind PIX

[danlanwanman]

Sorry I originally posted this as a reply to another thread.

I need help with the next step to configure my Exchange mail server to receive/send mail. I have tried unsuccessfully to make this happen so you will see my previous attempt. We have a pool of public IPs and previously we only used one IP for the Watchguard firewall and using a one-to-one NAT we were able to direct mail to HQ(our Exchange server). When that firebox died I substituted a SOHO6 and had it up in 5 minutes. This PIX501 is going on 3 hours!

All traffic is routing out just fine right now.

Router IP xxx.188.231.98
Internal IP 10.10.1.0-
Internal IP (HQ) 10.10.1.250

QUESTIONS:
In theory, do I need to use the public IP pool at all or can I just use the one IP?
Do I need to use a public IP on my mail server?


PIX Version 6.3(4)
interface ethernet0 auto
interface ethernet1 100full
nameif ethernet0 outside security0
nameif ethernet1 inside security100

hostname pixfirewall
domain-name ourdomain.org
clock timezone EST -5
clock summer-time EDT recurring
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 rsh 514
fixup protocol rtsp 554
fixup protocol sip 5060
fixup protocol sip udp 5060
fixup protocol skinny 2000
fixup protocol smtp 25
fixup protocol sqlnet 1521
fixup protocol tftp 69
names
name 10.10.1.0 ourdomain.org
name 10.10.1.250 HQ
access-list inbound permit tcp any any eq smtp
access-list inbound permit tcp any any eq www
access-list inbound permit tcp any any eq https
pager lines 24
mtu outside 1500
mtu inside 1500
ip address outside xxx.188.231.98 255.255.255.240
ip address inside 10.10.1.2 255.255.255.0
ip audit info action alarm
ip audit attack action alarm
pdm location HQ 255.255.255.255 inside
pdm logging informational 100
pdm history enable
arp timeout 14400
global (outside) 1 xxx.188.231.99-xxx.188.231.109
global (outside) 1 xxx.188.231.110
nat (inside) 1 0.0.0.0 0.0.0.0 0 0
static (inside,outside) tcp interface smtp HQ smtp netmask 255.255.255.255 0 0
static (inside,outside) tcp interface

http://www HQ

http://www netmask

255.255.255.255 0 0
static (inside,outside) tcp interface https HQ https netmask 255.255.255.255 0 0
static (inside,outside) HQ HQ netmask 255.255.255.255 0 0
access-group inbound in interface outside
route outside 0.0.0.0 0.0.0.0 xxx.188.65.97 1
timeout xlate 0:05:00
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 TACACS+ max-failed-attempts 3
aaa-server TACACS+ deadtime 10
aaa-server RADIUS protocol radius
aaa-server RADIUS max-failed-attempts 3
aaa-server RADIUS deadtime 10
aaa-server LOCAL protocol local
http server enable
http ourdomain.org 255.255.255.0 inside
no snmp-server location
no snmp-server contact
snmp-server community public
no snmp-server enable traps
floodguard enable
telnet timeout 5
ssh timeout 5
console timeout 0
terminal width 80
Cryptochecksum:05afeefc639cfc2e23b2cb4303d007ed

Dan
lost in IOSland!

 

[lgarner]

Try deleting the line "static (inside,outside) HQ HQ netmask 255.255.255.255 0 0".

Exchange also doesn't work well with smtp fixup, so you might try disabling that. Basic e-mail should work, though.

 

[danlanwanman]

I think that was left over froma previous attempt so I did remove that and I took you up on the

no fixup smtp 25 so it would be disabled.

Can you answer my theory questions...
In theory, do I need to use the public IP pool at all or can I just use the one IP?
Do I need to use a public IP on my mail server? If so, I understand that I need to add an MX record to the DNS on the AD. Not wanting to make too many changes at once.

TIA
Dan

 

[lgarner]

You don't need a public pool, one address is sufficient. There was a DOS vulnerability in the Pix, but I think it was two revs before yours.

You don't need a public IP on the mail server as long as its private address has a static NAT to a public one. Your first "static" statement should do it.

The static statement that you had, translating from HQ to HQ, is what you'd do if you had a public address on HQ and it was in a DMZ. We do this; most of our public servers are configured with real public addresses and translated to themselves.