Two network cards

[chmdan]

I have tried to setup a Debian box with two network cards. The first network card is used to access the internet and the second is used to access a windows 98 computer that is connected to an old apparatus. The connection with the w98 pc is through a network switch. I setup the /etc/network/interfaces file manually in this way:

auto lo
iface lo inet loopback

auto eth0
address 170.71.66.48
netmask 255.255.255.0
network 170.71.64.0
broadcast 170.71.64.1
gateway 170.71.64.1
dns-nameservers 138.71.2.13 138.71.254.1

auto eth1
address 192.168.1.100
netmask 255.255.255.0
network 192.168.1.0
broadcast 192.168.1.255

The problem that I have is that I can connect to the network for 2 to 5 minutes after is start, then I lose the connection. To recover the internet connection, I have to execute /etc/init.d/networking stop start. Also, when the internet connection is down I still can connect to the w98 pc with samba. I do not see any message when executing dmesg. Does any know what can be the cause of this problem?

[Irithori]

This public IP assignment doesnt make any sense

address 170.71.66.48
netmask 255.255.255.0
network 170.71.64.0
broadcast 170.71.64.1
gateway 170.71.64.1

The address 170.71.66.48 is not in the network 170.71.64.0/255.255.255.0
Also, given the netmask of 255.255.255.0, the broadcast is wrong.

Can you verify the information on the network settings?

[chmdan]

My bad the IP should be
170.71.64.48
And broadcast
170.71.64.255