Firewall Wizards mailing list archives
Re: Question about a Cisco PIX 515 - Routing question (I think)
From: "Bruce Smith" <bruce_the_loon () worldonline co za>
Date: Wed, 7 Jun 2006 17:44:23 +0200
Hi Charles This is because the external IP doesn't exist at all. The PIX accepts the packet from the Internet, changes the addressing to map the internal->external NAT and sends it on in. A return packet is handled in reverse. When you try that on the inside of the network, the packet is handled by the default route and sent onto the outside interface. At that point, the packet disappears into the bit-bucket because the PIX does not turn the packet around and send it back inside. In fact, I'm not even sure that the NAT rules come into play in this scenario, AFAIK, the rules apply to traffic inbound to an interface after the access-lists apply. PIX 7 is supposed to be able to hairpin an interface, but I've never configured this and cannot supply any further information on this feature. It may (unless your programs are too complex) be easier to get the servers to talk to each other on the internal 10.x ip addresses instead. If I've made any glaring mistakes, please feel free to reeducate me :_) Regards, Bruce Smith Firewall Administrator Nelson Mandela Metropolitan University South Africa ________________________________ From: firewall-wizards-bounces () listserv icsalabs com [mailto:firewall-wizards-bounces () listserv icsalabs com] On Behalf Of Charles Norton Sent: Tuesday, June 06, 2006 3:54 PM To: firewall-wizards () listserv icsalabs com Subject: [fw-wiz] Question about a Cisco PIX 515 - Routing question (I think) Hello everyone, I apologize if this is a question that has been answered previously (this is my first time joining the list, and posting to it as well) - I looked through some of the archives and couldn't find anything that addressed it (or maybe its likely that I don't know how to properly describe the issue). I have a Cisco Pix 515 UR, with PIX 7.04 OS and ASDM 5.04 (the newest of both). - I had my friend help me setup the box at his datacenter and for the most part its been working, except I realized recently once we moved all the servers behind it (they're all Virtual Machines running on a single box - which should be irrelevant I suppose) the machines were then unable to communicate with each other using their public IP #'s. Where this became obvious is that, I have 2 SMTP servers, one Exchange server and another is part of Plesk Hosting panel - when users on one system email users on another - they're using the @whatever.com domain name, which can't be resolved because those servers can't communicate on the public equivalents of what has been NAT'd to the private network which resides on 10.0.1.x A good way to describe is - if I go on a machine, it has IP of 10.0.1.23 (internal) which is NAT'd to an external IP of 38.118.71.83 (outside) - coming from the general Internet, if I hit that IP #, I would get a ping back, as well as a connection to the web server on there. - If I try to do the same FROM that machine, or from any other machine on the PIX, it can't find the route to connect. Does this make sense? Can anyone maybe offer any advice or guidance in the matter? If anyone might be able to lend some assistance I would be most grateful. Thank you, Charles _______________________________________________ firewall-wizards mailing list firewall-wizards () listserv icsalabs com https://listserv.icsalabs.com/mailman/listinfo/firewall-wizards
Current thread:
- Question about a Cisco PIX 515 - Routing question (I think) Charles Norton (Jun 06)
- Re: Question about a Cisco PIX 515 - Routing question (I think) Brian Loe (Jun 07)
- Re: Question about a Cisco PIX 515 - Routing question (I think) Sanford Reed (Jun 07)
- Re: Question about a Cisco PIX 515 - Routing question (I think) Bruce Smith (Jun 07)
- Re: Question about a Cisco PIX 515 - Routing question (I think) chad hutchison (Jun 08)