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* redundancy with linux and two NIC
@ 2003-06-13 17:16 Ivan Rodriguez
  2003-06-13 19:19 ` Ramin Dousti
  0 siblings, 1 reply; 4+ messages in thread
From: Ivan Rodriguez @ 2003-06-13 17:16 UTC (permalink / raw)
  To: netfilter

Hi 
i have the next situation

                          ADSL
                   eth1--------->
192.168.64.x --->LinuxBox
                   eth0--------->
                          DS0
 
my Linux box is a GW i need the following:
         

        if etho is down then all traffic is routed
        by eth1 and  if eth1 is down then all 
        traffic is routed by eth0

it is posible ?
please help me and excusme mi english is not god


Destination     Gateway         Genmask         Flags 
 MSS Window  irtt
Iface

148.223.133.227 192.168.65.1    255.255.255.255 UGH   
  40 0          0
eth1

148.223.182.205 0.0.0.0         255.255.255.255 UH    
  40 0          0
ppp0

192.168.65.0    192.168.65.1    255.255.255.0   UG    
  40 0          0
eth1

192.168.65.0    0.0.0.0         255.255.255.0   U     
  40 0          0
eth1

10.0.0.0        0.0.0.0         255.0.0.0       U     
  40 0          0
eth0

127.0.0.0       0.0.0.0         255.0.0.0       U     
  40 0          0
lo

0.0.0.0         148.223.182.205 0.0.0.0         UG    
  40 0          0
ppp0
























_________________________________________________________
Do You Yahoo!?
La mejor conexión a internet y 25MB extra a tu correo por $100 al mes. http://net.yahoo.com.mx


^ permalink raw reply	[flat|nested] 4+ messages in thread

* RE: redundancy with linux and two NIC
@ 2003-06-13 17:44 Daniel Chemko
  0 siblings, 0 replies; 4+ messages in thread
From: Daniel Chemko @ 2003-06-13 17:44 UTC (permalink / raw)
  To: Ivan Rodriguez, netfilter


I want that too!

The only immediate way I can imagine that happening is writing a monitoring script that keeps checking the availability of each channel, and then when it fails, call a script to modify your iptables and routing configuration to point to the new configuration. I sorta have this setup, but I haven't implemented the poller, so I need to manually switch over when there is a failure...

If anyone knows a more elegant approach, I am all ears.

-----Original Message-----
From: Ivan Rodriguez [mailto:ivanoch79@yahoo.com.mx] 
Sent: Friday, June 13, 2003 10:17 AM
To: netfilter@lists.netfilter.org
Subject: redundancy with linux and two NIC

Hi 
i have the next situation

                          ADSL
                   eth1--------->
192.168.64.x --->LinuxBox
                   eth0--------->
                          DS0
 
my Linux box is a GW i need the following:
         

        if etho is down then all traffic is routed
        by eth1 and  if eth1 is down then all 
        traffic is routed by eth0

it is posible ?
please help me and excusme mi english is not god


Destination     Gateway         Genmask         Flags 
 MSS Window  irtt
Iface

148.223.133.227 192.168.65.1    255.255.255.255 UGH   
  40 0          0
eth1

148.223.182.205 0.0.0.0         255.255.255.255 UH    
  40 0          0
ppp0

192.168.65.0    192.168.65.1    255.255.255.0   UG    
  40 0          0
eth1

192.168.65.0    0.0.0.0         255.255.255.0   U     
  40 0          0
eth1

10.0.0.0        0.0.0.0         255.0.0.0       U     
  40 0          0
eth0

127.0.0.0       0.0.0.0         255.0.0.0       U     
  40 0          0
lo

0.0.0.0         148.223.182.205 0.0.0.0         UG    
  40 0          0
ppp0
























_________________________________________________________
Do You Yahoo!?
La mejor conexión a internet y 25MB extra a tu correo por $100 al mes. http://net.yahoo.com.mx



^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: redundancy with linux and two NIC
  2003-06-13 17:16 redundancy with linux and two NIC Ivan Rodriguez
@ 2003-06-13 19:19 ` Ramin Dousti
  0 siblings, 0 replies; 4+ messages in thread
From: Ramin Dousti @ 2003-06-13 19:19 UTC (permalink / raw)
  To: Ivan Rodriguez; +Cc: netfilter

On Fri, Jun 13, 2003 at 12:16:52PM -0500, Ivan Rodriguez wrote:

> Hi 
> i have the next situation
> 
>                           ADSL
>                    eth1--------->
> 192.168.64.x --->LinuxBox
>                    eth0--------->
>                           DS0
>  
> my Linux box is a GW i need the following:
>          
> 
>         if etho is down then all traffic is routed
>         by eth1 and  if eth1 is down then all 
>         traffic is routed by eth0
> 
> it is posible ?

Yes, it is possible but not easy. First of all, if a link goes down, so does
your MASQ'ed sessions. You just can't switch the masq'ing interface. Secondly,
the inbound initiations are totally out of your control. If someone sends you
a packet with dst (eth0) and eth0 is down, the packet would be dropped (with
an appropriate ICMP generated). I'm sure there are other deficiencies to this
setup. One way of setting this up is to have a static IP assigned to a loopback
(dummy device in linux terminology) on the linux box and have your ISP's (both
if there are two) route that IP to you through your both interfaces. Then you
would SNAT everything with that IP and set up your routes (with or without an
equal cost) to both interfaces. Unfortunately in home setups the ethX might
show up while the link is basically down, which means you have to monitor your
next-hop access and remove the unreachable route if necessary, otherwise you'll
create a blackhole for yourself. At any rate, you need a static IP and two (or
one) willing ISP(s) to route that IP to you... From your routing table below
it looks like you have eth1 and ppp0 to the Internet which seem to be on
the same /18. So you're one step closer to this solution...

Ramin

> please help me and excusme mi english is not god
> 
> 
> Destination     Gateway         Genmask         Flags 
>  MSS Window  irtt
> Iface
> 
> 148.223.133.227 192.168.65.1    255.255.255.255 UGH   
>   40 0          0
> eth1
> 
> 148.223.182.205 0.0.0.0         255.255.255.255 UH    
>   40 0          0
> ppp0
> 
> 192.168.65.0    192.168.65.1    255.255.255.0   UG    
>   40 0          0
> eth1
> 
> 192.168.65.0    0.0.0.0         255.255.255.0   U     
>   40 0          0
> eth1
> 
> 10.0.0.0        0.0.0.0         255.0.0.0       U     
>   40 0          0
> eth0
> 
> 127.0.0.0       0.0.0.0         255.0.0.0       U     
>   40 0          0
> lo
> 
> 0.0.0.0         148.223.182.205 0.0.0.0         UG    
>   40 0          0
> ppp0


^ permalink raw reply	[flat|nested] 4+ messages in thread

* RE: redundancy with linux and two NIC
@ 2003-06-15 22:35 George Vieira
  0 siblings, 0 replies; 4+ messages in thread
From: George Vieira @ 2003-06-15 22:35 UTC (permalink / raw)
  To: netfilter

You need to use iproute2 for redundancy routing. iptables isn't really for that kind of job I think..

Here's a link that can help you that I found to be pretty good...

http://www.samag.com/documents/s=1824/sam0201h/0201h.htm


Thanks,
____________________________________________
George Vieira
Systems Manager
georgev@citadelcomputer.com.au

Citadel Computer Systems Pty Ltd
http://www.citadelcomputer.com.au

Phone   : +61 2 9955 2644
HelpDesk: +61 2 9955 2698
 

-----Original Message-----
From: Ivan Rodriguez [mailto:ivanoch79@yahoo.com.mx]
Sent: Saturday, June 14, 2003 3:17 AM
To: netfilter@lists.netfilter.org
Subject: redundancy with linux and two NIC


Hi 
i have the next situation

                          ADSL
                   eth1--------->
192.168.64.x --->LinuxBox
                   eth0--------->
                          DS0
 
my Linux box is a GW i need the following:
         

        if etho is down then all traffic is routed
        by eth1 and  if eth1 is down then all 
        traffic is routed by eth0

it is posible ?
please help me and excusme mi english is not god



^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2003-06-15 22:35 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2003-06-13 17:16 redundancy with linux and two NIC Ivan Rodriguez
2003-06-13 19:19 ` Ramin Dousti
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2003-06-13 17:44 Daniel Chemko
2003-06-15 22:35 George Vieira

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