Re: Questions on IPFW???
Thanks buddy...I appreciate it. -Original Message- From: Chuck Swiger <[EMAIL PROTECTED]> Sent: Aug 3, 2004 1:11 PM To: "Hakim Z. Singhji" <[EMAIL PROTECTED]>, freebsd Questions <[EMAIL PROTECTED]> Subject: Re: Questions on IPFW??? Hakim Z. Singhji wrote: > You answered my question, I wanted to know which was better to use with > port forwarding (ipfw or natd) and based on what you wrote, natd is a > better fit due to the fact that I would not have to force the other machine > to accept packets redirected from the NAT box using natd. Is that > correct??? That's right. Most people want to use NAT, because it lets you set up an internal network without having to specially configure the internal machines. With regard to your other question, if you want an external connection to, say, port 22 to be forwarded to port 22 on some machine on your internal network, use: redirect_port tcp 192.0.0.5:22 22 ...in /etc/natd.conf or your natd_flags in /etc/rc.conf. -- -Chuck ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: Questions on IPFW???
Hakim Z. Singhji wrote: You answered my question, I wanted to know which was better to use with port forwarding (ipfw or natd) and based on what you wrote, natd is a better fit due to the fact that I would not have to force the other machine to accept packets redirected from the NAT box using natd. Is that correct??? That's right. Most people want to use NAT, because it lets you set up an internal network without having to specially configure the internal machines. With regard to your other question, if you want an external connection to, say, port 22 to be forwarded to port 22 on some machine on your internal network, use: redirect_port tcp 192.0.0.5:22 22 ...in /etc/natd.conf or your natd_flags in /etc/rc.conf. -- -Chuck ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: Questions on IPFW???
Actually Chuck, You answered my question, I wanted to know which was better to use with port forwarding (ipfw or natd) and based on what you wrote, natd is a better fit due to the fact that I would not have to force the other machine to accept packets redirected from the NAT box using natd. Is that correct??? -Original Message- From: "Hakim Z. Singhji" <[EMAIL PROTECTED]> Sent: Aug 3, 2004 12:49 PM To: Chuck Swiger <[EMAIL PROTECTED]> Cc: [EMAIL PROTECTED] Subject: Re: Questions on IPFW??? Hello Chuck, I was wondering if someone could help me answer some questions I have concerning IPFW vs. natd I am trying to allow my FreeBSD 4.10 gateway to perform port forwarding for SSH, SQL*Net and Webservice (Web not as important yet). I wanted to know if I can use IPFW as opposed to natd to redirect or pass TCP & UDP (is ICMP out of the question???) to a remote location. Gateway::192.0.0.1:22 --> remote server 192.0.0.5:22 or 192.0.0.5:9881 for instance. From the configuration of ipfw it appears that it can be done instead of using natd. Any suggestions or corrections of my logic welcome. Thanks in advance. HZS -Original Message- From: Chuck Swiger <[EMAIL PROTECTED]> Sent: Aug 3, 2004 12:40 PM To: "Hakim Z. Singhji" <[EMAIL PROTECTED]> Cc: [EMAIL PROTECTED] Subject: Re: Questions on IPFW??? Hakim Z. Singhji wrote: > Question, when NAT overloading is it possible to use only IPFW rules to > pass TCP/UDP packects to remote ip addresses within the network? I don't know what "NAT overloading" means. It is possible to use only IPFW rules to pass TCP & UDP packets from one interface to another using the fwd action. However, note that: The fwd action does not change the contents of the packet at all. In particular, the destination address remains unmodified, so packets forwarded to another system will usually be rejected by that system unless there is a matching rule on that system to capture them. For packets forwarded locally, the local address of the socket will be set to the original destination address of the packet. This makes the netstat(1) entry look rather weird but is intended for use with transparent proxy servers. > Or do you have to use natd...because IPFW allows you to execute > the following for example: > > ip from 192.168.99.100 80 to 192.168.99.101 9981 > That's the body of an IPFW rule which matches packets with those attributes. Without an action ("allow", "deny", "fwd"), what you've written isn't a complete rule: it doesn't mean anything by itself. > or even in conjunction with a dummynet rule of somesort? Um. Do you understand the question you are asking? I don't-- perhaps try using a complete sentence. Better yet, why don't you tell us what your network looks like and what you want to do. You most likely will receive answers which are more specific and more useful to you... -- -Chuck ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]" ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: Questions on IPFW???
Hello Chuck, I was wondering if someone could help me answer some questions I have concerning IPFW vs. natd I am trying to allow my FreeBSD 4.10 gateway to perform port forwarding for SSH, SQL*Net and Webservice (Web not as important yet). I wanted to know if I can use IPFW as opposed to natd to redirect or pass TCP & UDP (is ICMP out of the question???) to a remote location. Gateway::192.0.0.1:22 --> remote server 192.0.0.5:22 or 192.0.0.5:9881 for instance. From the configuration of ipfw it appears that it can be done instead of using natd. Any suggestions or corrections of my logic welcome. Thanks in advance. HZS -Original Message- From: Chuck Swiger <[EMAIL PROTECTED]> Sent: Aug 3, 2004 12:40 PM To: "Hakim Z. Singhji" <[EMAIL PROTECTED]> Cc: [EMAIL PROTECTED] Subject: Re: Questions on IPFW??? Hakim Z. Singhji wrote: > Question, when NAT overloading is it possible to use only IPFW rules to > pass TCP/UDP packects to remote ip addresses within the network? I don't know what "NAT overloading" means. It is possible to use only IPFW rules to pass TCP & UDP packets from one interface to another using the fwd action. However, note that: The fwd action does not change the contents of the packet at all. In particular, the destination address remains unmodified, so packets forwarded to another system will usually be rejected by that system unless there is a matching rule on that system to capture them. For packets forwarded locally, the local address of the socket will be set to the original destination address of the packet. This makes the netstat(1) entry look rather weird but is intended for use with transparent proxy servers. > Or do you have to use natd...because IPFW allows you to execute > the following for example: > > ip from 192.168.99.100 80 to 192.168.99.101 9981 > That's the body of an IPFW rule which matches packets with those attributes. Without an action ("allow", "deny", "fwd"), what you've written isn't a complete rule: it doesn't mean anything by itself. > or even in conjunction with a dummynet rule of somesort? Um. Do you understand the question you are asking? I don't-- perhaps try using a complete sentence. Better yet, why don't you tell us what your network looks like and what you want to do. You most likely will receive answers which are more specific and more useful to you... -- -Chuck ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: Questions on IPFW???
Hakim Z. Singhji wrote: Question, when NAT overloading is it possible to use only IPFW rules to pass TCP/UDP packects to remote ip addresses within the network? I don't know what "NAT overloading" means. It is possible to use only IPFW rules to pass TCP & UDP packets from one interface to another using the fwd action. However, note that: The fwd action does not change the contents of the packet at all. In particular, the destination address remains unmodified, so packets forwarded to another system will usually be rejected by that system unless there is a matching rule on that system to capture them. For packets forwarded locally, the local address of the socket will be set to the original destination address of the packet. This makes the netstat(1) entry look rather weird but is intended for use with transparent proxy servers. Or do you have to use natd...because IPFW allows you to execute the following for example: ip from 192.168.99.100 80 to 192.168.99.101 9981 That's the body of an IPFW rule which matches packets with those attributes. Without an action ("allow", "deny", "fwd"), what you've written isn't a complete rule: it doesn't mean anything by itself. or even in conjunction with a dummynet rule of somesort? Um. Do you understand the question you are asking? I don't-- perhaps try using a complete sentence. Better yet, why don't you tell us what your network looks like and what you want to do. You most likely will receive answers which are more specific and more useful to you... -- -Chuck ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Questions on IPFW???
Hey guys, Question, when NAT overloading is it possible to use only IPFW rules to pass TCP/UDP packects to remote ip addresses within the network? Or do you have to use natd...because IPFW allows you to execute the following for example: ip from 192.168.99.100 80 to 192.168.99.101 9981 or even in conjunction with a dummynet rule of somesort? Hakim Z. Singhji New York University pub 1024D/A4F3B64A 2004-07-30 Hakim Z. Singhji (NYU) <[EMAIL PROTECTED]> Key fingerprint = 1407 12D9 73F2 5C38 45CE C387 953F 5657 A4F3 B64A ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"