[VLAN] NAT - VLAN - Route - Problem

[Jeremy SALMON]

Hi,

I'm completly lost with vlan and route configuration on my debian.

This is my architecture :


eth1.401                  eth1.2338               eth2
Voice Vlan              Public IP                  Local Network
10.150.11.90          84.16.x.x                 192.168.1.1
255.255.255.240   255.255.255.128  255.255.255.0
               |                          |                          |

                                         BOX

In this box I use :
    - NAT to allow the eth2 client connect to Internet from 84.16.x.x
    - Asterisk. Phones are in the eth2 network, SIP provider are in  
eth1.401

No default gateway in network card.

A simple script to create route and allow NAT and other things...

============= SCRIPT ==================

# Activate IP Forward
echo 1 > /proc/sys/net/ipv4/ip_forward

# Init Iptables
iptables -F
iptables -t nat -F

# NAT
iptables -t nat -A POSTROUTING -o eth0.2338 -s 192.168.1.0/24 -d!  
10.0.0.0/8 -j SNAT --to 84.16.x.x

# Add route for Internet Traffic
route add default gw 84.16.x.x
# Add route for my SIP provider. Route all traffic to 10.0.0.0
route add -net 10.0.0.0 netmask 255.0.0.0 gw 10.150.11.1

============= END OF SCRIPT ============

I have a sip phone 192.168.1.200 gateway 192.168.1.1
I have my notebook 192.168.1.100 gateway 192.168.1.1

When I only ping external IP (for example 212.217.0.1) from my  
laptop, everything is ok. eth1.2338 is in use
When I only make a call through SIP provider 10.x.x.x everything is  
ok. eth1.401 is in use

So it seem route are working....

But for example when I make a call and during this call I ping  
212.217.0.1 ping lose 95% of packet. And immediately after hangup the  
phone, ping start to work ok....

In IPTRAF I see all the ICMP packet sent throught eth1.2338, and all  
the udp phone traffic sent through eth1.401.

But it seem ping don't receive the response, or response arrive to  
the eth1.401....

When I ping 212.217.0.1, and during the ping make a call, all the  
incoming udp traffic is lost...

Someone can help me with this configuration ? I'm completely lost.....

Thanks in advance,
Jeremy