Hi all,

Ubuntu 14.04

Previously before adding a router following entry on
/etc/network/interfaces worked to connect Internet without problem;
Code:
auto lo
iface lo inet loopback

# The primary network interface
auto eth0
iface eth0 inet static
        address         aaa.aaa.aaa.aaa
        dns-nameservers bbb.bbb.bbb.bbb ccc.ccc.ccc.ccc
        netmask         255.255.255.0
        broadcast       aaa.aaa.aaa.15
        gateway         aaa.aaa.aaa.13

# add bridge ports
auto br0
iface br0 inet static
        address         192.168.0.100
        dns-nameservers bbb.bbb.bbb.bbb ccc.ccc.ccc.ccc
        network         192.168.0.0
        netmask         255.255.255.0
        broadcast       192.168.0.255
        gateway         192.168.0.1
        bridge_ports    eth0
        bridge_fd       9
        bridge_hello    2
        bridge_maxage   12
        bridge_stop     off
The addresses "aaa.aaa.aaa.aaa bbb.bbb.bbb.bbb ccc.ccc.ccc.ccc 255.255.255.0 aaa.aaa.aaa.15 aaa.aaa.aaa.13' all were provided by ISP.

I haven't used the captioned settings at least more than ONE year after adding a router.

I just tested it lately and found it didn't work. Please help.

This is a Test. Currently I'm subscribing PTTC fibre broadband 100Mbps upload/download, static IP. The last section is an Ethernet cable which I use to plugin to the router or to the network card of PC. The contract shall end at early April, 2016. I shall switch my subscription to another ISP of PTTH fibre broadband 1000Mbps upload/download, dynamic IP.

If this setting still works for me, then for Dynamic IP I just delete follows;
Code:
address aaa.aaa.aaa.aaa
dns-nameservers bbb.bbb.bbb.bbb ccc.ccc.ccc.ccc
netmask 255.255.255.0
broadcast aaa.aaa.aaa.15
gateway aaa.aaa.aaa.13
and change;
Code:
iface eth0 inet static
to;
Code:
iface eth0 inet dhcp
Thanks in advance.

Regards