[ale] NAT Help needed!

[Philip Polstra]

Nothing is showing up in the logs?!

The address of eth1 which is connected to the local network is
192.168.1.5.  Eth0 is connected to the ISP using DHCP off a 10.0.0.0
network.

I can ping 192.168.1.5 from anywhere and also can ping from the router
machine to anywhere inside or outside the network.  The other machines
(which dual boot FC3/Windozes) have the gateway set to 192.168.1.5.




On Wed, 9 Feb 2005 14:03:08 -0500, Robert L. Harris
<Robert.L.Harris at rdlg.net> wrote:
> 
> 
> Ok, do this:
> 
>   Make sure that your iptable output error messages are being logged.  I
> do it with this:
> 
> $IPTABLES -A cleanup -j LOG --log-level debug --log-prefix "IPTables v4 Dropped: "
> $IPTABLES -A cleanup -j DROP
> 
> That way you can check to see if it's your firewall with this:
> 
> {130}:/var/log>tail -20f syslog | grep IPT
> Feb  9 13:59:29 wally kernel: IPTables v4 Dropped: IN=eth0 OUT= MAC=00:60:08:1c:7a:b5:00:0b:bf:7c:cc:a8:08:00 SRC=70.49.25.19 DST=68.184.148.196 LEN=48 TOS=0x00 PREC=0x00 TTL=110 ID=10687 DF PROTO=TCP SPT=2044 DPT=21505 WINDOW=65535 RES=0x00 SYN URGP=0
> Feb  9 13:59:35 wally kernel: IPTables v4 Dropped: IN=eth0 OUT= MAC=00:60:08:1c:7a:b5:00:0b:bf:7c:cc:a8:08:00 SRC=70.49.25.19 DST=68.184.148.196 LEN=48 TOS=0x00 PREC=0x00 TTL=110 ID=11136 DF PROTO=TCP SPT=2044 DPT=21505 WINDOW=65535 RES=0x00 SYN URGP=0
> 
> That way you can get a machine behind to ping out and see where you're
> getting blocked.
> 
> 
> Thus spake Philip Polstra (ppolstra at gmail.com):
> 
> > On Wed, 9 Feb 2005 13:48:26 -0500, Robert L. Harris
> > <Robert.L.Harris at rdlg.net> wrote:
> > >
> > >
> > > Ok, from the FC3, can you ping the default gateway outwards to the
> > > Internet?  Can you ping a couple machines behind the FC3 in the nat'd
> > > area?
> > Yes, and yes.
> > >
> > > What do you get for "cat /proc/sys/net/ipv4/ip_forward"?
> > 1
> > >
> > > Thus spake Philip Polstra (ppolstra at gmail.com):
> > >
> > > > Our router went down yesterday at the high school so we decided to set
> > > > up a FC3 machine to be the new router.  I can't get it to forward
> > > > packets from other machines in the network despite following the
> > > > instructions to set up the router with NAT exactly.  I have the
> > > > ability to connect to the internet and the local network on the router
> > > > machine, but nothing gets forwarded.
> > > >
> > > > I'm using iptables.  Any ideas?
> > > > _______________________________________________
> > > > Ale mailing list
> > > > Ale at ale.org
> > > > http://www.ale.org/mailman/listinfo/ale
> > >
> > > :wq!
> > > ---------------------------------------------------------------------------
> > > Robert L. Harris                     | GPG Key ID: E344DA3B
> > >                                          @ x-hkp://pgp.mit.edu
> > > DISCLAIMER:
> > >       These are MY OPINIONS             With Dreams To Be A King,
> > >        ALONE.  I speak for              First One Should Be A Man
> > >        no-one else.                       - Manowar
> > >
> > >
> > >
> >
> >  ** CRM114 Whitelisted by: mit.edu **
> 
> :wq!
> ---------------------------------------------------------------------------
> Robert L. Harris                     | GPG Key ID: E344DA3B
>                                          @ x-hkp://pgp.mit.edu
> DISCLAIMER:
>       These are MY OPINIONS             With Dreams To Be A King,
>        ALONE.  I speak for              First One Should Be A Man
>        no-one else.                       - Manowar
> 
> 
>