Re: [LARTC] Weird problems with source-based routing, proxy_arp and

[Julian Anastasov <ja@ssi.bg>]

	Hello,

On Fri, 29 Nov 2002, Janssen Alexander wrote:

> ip route add 10.1.56.222 dev eth1 # Router1
> ip route add 10.1.56.193 dev eth0 # Workstation1
> # every Workstation has it's own table
> ip rule add from 10.1.56.193 table 193
> ip route add default via 10.1.56.222 dev eth1 table 193
>
> In my understanding the firewall should not answer to
> arp-whois requests for IP 10.1.56.193 on interface eth0.
> Or did i get it wrong?

	Yes

	May be only one missing line to be happy with medium_id:

ip rule add prio 100 table main

	Explanation:

	I see only the table for .193 but I assume there are other
similar tables, you have asymmetric routing configured when it should
not be in this way. What happens:

A and B are on same LAN, Host A resolves B:

who-has B tell A

firewall:

Q: I see probe "who-has B tell A" on dev X. Where points the route
from A to B?

A: There is route "from A to 0/0 => Forward via DEV Y". Well, X != Y,
they have different medium_id values => answer this ARP probe on DEV X.

The problem is that you have routes in this order (ip rule show):

from A to 0/0 => DEV Y (table A)
from 0/0 to B => DEV X (table main)

You need to inspect the main table first.

Regards

--
Julian Anastasov <ja@ssi.bg>

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