IP Masq - Ping & Telnet ok, but HTTP & FTP don't work

IP Masq - Ping & Telnet ok, but HTTP & FTP don't work

Post by heapa.. » Wed, 19 Apr 2000 04:00:00



Hi All,

I have a strange problem with using IP Masq.  The
Linux box (Slackware 7) is set up as a gateway to
a DSL connection.  I've gone over (and over) the
howto's/FAQ's, and the setup appears fine, but
the problem persists...

I can ping and telnet to the world from all the
Masq'd computers, but can't get to any web or ftp
sites, not even when sitting at the gateway
machine using lynx.

From all the testing/FAQ's I've read, it seems
that if ping and telnet work, so should http &
ftp.  Is that correct?  If so, then it doesn't
matter what modules I have loaded, right?

Is there a separate module for http?

I'm using ipfwadm rather than ipchains, because I
didn't realize at the time that ipchains is the
way to go for kernel 2.2.x.  I'll change that
tonight, but I don't see why that would matter.

Anyway, this is my first attempt at setting up a
gateway like this, so it quite possible that I'm
missing something really silly.

If any of you can get me pointed in the right
direction, I'd really appreciate it!

Sent via Deja.com http://www.deja.com/
Before you buy.

 
 
 

IP Masq - Ping & Telnet ok, but HTTP & FTP don't work

Post by scumbucke » Wed, 19 Apr 2000 04:00:00


Quote:> I'm using ipfwadm rather than ipchains, because I
> didn't realize at the time that ipchains is the
> way to go for kernel 2.2.x.  I'll change that
> tonight, but I don't see why that would matter.

> Anyway, this is my first attempt at setting up a
> gateway like this, so it quite possible that I'm
> missing something really silly.

> If any of you can get me pointed in the right
> direction, I'd really appreciate it!

I've got a few files that might do you some good. Email me if you'd
like me to email them to you.
One is an script that updates your firewall rules every time your ip
address changes. The other updates a page on your website that provides
your ip address. Trust me, this really works and is easy to use.

Sent via Deja.com http://www.deja.com/
Before you buy.

 
 
 

IP Masq - Ping & Telnet ok, but HTTP & FTP don't work

Post by bouvr.. » Wed, 19 Apr 2000 04:00:00


    Hi!

    I had the same problem yesterday... And I found that late at
night... In fact, the problems probably doesn't come from your
masquerading gateway.... The thing is that if you are using DSL through
pppoe the MTU of the interface shouldn't be above 1400 or you get into
trouble....

    What I did is to set the MTU to 1400 on the clients machine... To do
this issue the following command on all the machines behind the
firewall:

   ifconfig eth0 mtu 1400

    eth0 being the nic connected your LAN.... Try http again and it
should work....

            JU


> Hi All,

> I have a strange problem with using IP Masq.  The
> Linux box (Slackware 7) is set up as a gateway to
> a DSL connection.  I've gone over (and over) the
> howto's/FAQ's, and the setup appears fine, but
> the problem persists...

> I can ping and telnet to the world from all the
> Masq'd computers, but can't get to any web or ftp
> sites, not even when sitting at the gateway
> machine using lynx.

> From all the testing/FAQ's I've read, it seems
> that if ping and telnet work, so should http &
> ftp.  Is that correct?  If so, then it doesn't
> matter what modules I have loaded, right?

> Is there a separate module for http?

> I'm using ipfwadm rather than ipchains, because I
> didn't realize at the time that ipchains is the
> way to go for kernel 2.2.x.  I'll change that
> tonight, but I don't see why that would matter.

> Anyway, this is my first attempt at setting up a
> gateway like this, so it quite possible that I'm
> missing something really silly.

> If any of you can get me pointed in the right
> direction, I'd really appreciate it!

> Sent via Deja.com http://www.deja.com/
> Before you buy.

 
 
 

IP Masq - Ping & Telnet ok, but HTTP & FTP don't work

Post by Kaj ten Voord » Thu, 20 Apr 2000 04:00:00


Would this also be the case for cable connections?

>    Hi!

>    I had the same problem yesterday... And I found that late at
>night... In fact, the problems probably doesn't come from your
>masquerading gateway.... The thing is that if you are using DSL through
>pppoe the MTU of the interface shouldn't be above 1400 or you get into
>trouble....

>    What I did is to set the MTU to 1400 on the clients machine... To do
>this issue the following command on all the machines behind the
>firewall:

>   ifconfig eth0 mtu 1400

>    eth0 being the nic connected your LAN.... Try http again and it
>should work....

>            JU


>> Hi All,

>> I have a strange problem with using IP Masq.  The
>> Linux box (Slackware 7) is set up as a gateway to
>> a DSL connection.  I've gone over (and over) the
>> howto's/FAQ's, and the setup appears fine, but
>> the problem persists...

>> I can ping and telnet to the world from all the
>> Masq'd computers, but can't get to any web or ftp
>> sites, not even when sitting at the gateway
>> machine using lynx.

>> From all the testing/FAQ's I've read, it seems
>> that if ping and telnet work, so should http &
>> ftp.  Is that correct?  If so, then it doesn't
>> matter what modules I have loaded, right?

>> Is there a separate module for http?

>> I'm using ipfwadm rather than ipchains, because I
>> didn't realize at the time that ipchains is the
>> way to go for kernel 2.2.x.  I'll change that
>> tonight, but I don't see why that would matter.

>> Anyway, this is my first attempt at setting up a
>> gateway like this, so it quite possible that I'm
>> missing something really silly.

>> If any of you can get me pointed in the right
>> direction, I'd really appreciate it!

>> Sent via Deja.com http://www.deja.com/
>> Before you buy.

 
 
 

IP Masq - Ping & Telnet ok, but HTTP & FTP don't work

Post by Julien Bouvrai » Fri, 21 Apr 2000 04:00:00


    Well if you are meant to connect to your cable operator via pppoe, it
would be the same...

            JU


> Would this also be the case for cable connections?


> >    Hi!

> >    I had the same problem yesterday... And I found that late at
> >night... In fact, the problems probably doesn't come from your
> >masquerading gateway.... The thing is that if you are using DSL through
> >pppoe the MTU of the interface shouldn't be above 1400 or you get into
> >trouble....

> >    What I did is to set the MTU to 1400 on the clients machine... To do
> >this issue the following command on all the machines behind the
> >firewall:

> >   ifconfig eth0 mtu 1400

> >    eth0 being the nic connected your LAN.... Try http again and it
> >should work....

> >            JU


> >> Hi All,

> >> I have a strange problem with using IP Masq.  The
> >> Linux box (Slackware 7) is set up as a gateway to
> >> a DSL connection.  I've gone over (and over) the
> >> howto's/FAQ's, and the setup appears fine, but
> >> the problem persists...

> >> I can ping and telnet to the world from all the
> >> Masq'd computers, but can't get to any web or ftp
> >> sites, not even when sitting at the gateway
> >> machine using lynx.

> >> From all the testing/FAQ's I've read, it seems
> >> that if ping and telnet work, so should http &
> >> ftp.  Is that correct?  If so, then it doesn't
> >> matter what modules I have loaded, right?

> >> Is there a separate module for http?

> >> I'm using ipfwadm rather than ipchains, because I
> >> didn't realize at the time that ipchains is the
> >> way to go for kernel 2.2.x.  I'll change that
> >> tonight, but I don't see why that would matter.

> >> Anyway, this is my first attempt at setting up a
> >> gateway like this, so it quite possible that I'm
> >> missing something really silly.

> >> If any of you can get me pointed in the right
> >> direction, I'd really appreciate it!

> >> Sent via Deja.com http://www.deja.com/
> >> Before you buy.

 
 
 

1. On a Linux router, ftp& telnet works but ping doesn't work .

Hi all

I am setting up a Linux router with a Redhat 6.2 machine (But it has a
specially made Linux 2.4 kernel) with two Intel Pro/100+ cards. The
card at eth0 has an ip address of 192.168.150.177 and it is connect to
a switch with subnet 192.168.150.160/27. The eth1 card
(192.168.150.193) is connected to a hub and this network has the
subnet of 192.168.150.192/28. A host machine with an Intel Pro/100+
card and an ip address of 192.168.150.194 is also connected to the
hub. From the router machine, I can ping and telnet into the
192.168.150.194 host machine. However, I cannot ping from the
192.168.150.194 machine to the router(192.168.150.193). But oddly, I
can ftp and telent????? Have anyone experienced this problems before.
Also, both machine connecting to the hub are connect to the regular
port (No uplink). Thank you

Peter

2. Inode Reporting

3. ip masq - http doesn't work - telnet does

4. Netscape Commerce Web Server

5. ping works telnet/ftp don't (ppp/local net)

6. Adaptec Isa Card

7. ping works, telnet and ftp don't

8. recover deleted files

9. ping,traceroute,dns work; telnet,ftp don't - help (LNE100TX, tulip 0.9.13

10. ip masquerade - ftp works http don't

11. Ping OK; but Telnet, http, ftp fail!

12. ping ok, not telnet ftp http

13. Weird - Ping, traceroute problems - but telnet, http, ftp ok - ??