Can't change the default gateway with static IP

Question

I have this server for a while, and was present on other questions.

A while ago, I've changed the network and the gateway IP was changed too.
Since then, there is no internet on this machine.

I need access to the internet to update the machine and (sometimes) to install packages I need for development.

What I've tried:

route add default gw 192.168.1.1 (https://unix.stackexchange.com/a/259046/133591)
ip route replace default via 192.168.1.1 (https://unix.stackexchange.com/a/199070/133591)
ip route add default via 192.168.1.1 dev eth0 (https://unix.stackexchange.com/a/259048/133591)

Editing the file /etc/network/interfaces, to look like below:

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

source /etc/network/interfaces.d/*

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto eth0
allow-hotplug eth0
#iface eth0 inet dhcp
iface eth0 inet static
    address 192.168.1.205
    netmask 255.255.255.0
    gateway 192.168.1.1
    broadcast 192.168.1.1

And this is the result of all my attempts:

root@webtest:~# route add default gw 192.168.1.1
SIOCADDRT: Network is unreachable
root@webtest:~# ip route replace default via 192.168.1.1
RTNETLINK answers: Invalid argument
root@webtest:~# ip route add default via 192.168.1.1 dev eth0
RTNETLINK answers: Invalid argument
root@webtest:~#

The most bizarre thing is the SIOCADDRT: Network is unreachable error, when I'm clearly connected using SSH, which used the network.

What else should I try? I don't even know what else to do.

My system is running Debian 8.2 x64, with a single interface network.

Note:

I have read How can I change the default gateway? and How to set the Default gateway (which is where I got all those tries from).

The accepted answer on How can I change the default gateway? is a FreeBDS-exclusive answer.

Running ip addr and ip route gives the following:

root@webtest:~# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:1a:92:47:00:b5 brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.205/24 brd 192.168.1.1 scope global eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::21a:92ff:fe47:b5/64 scope link
       valid_lft forever preferred_lft forever
root@webtest:~# ip route
192.168.1.0/24 dev eth0  proto kernel  scope link  src 192.168.1.205
root@webtest:~#

Edit 1:

After the change that @Johan Myréen suggested, the result is still the same.

Below is the updated ip addr with 2 pings:

root@webtest:~# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:1a:92:47:00:b5 brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.205/24 brd 192.168.1.255 scope global eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::21a:92ff:fe47:b5/64 scope link
       valid_lft forever preferred_lft forever
root@webtest:~# ip route
default via 192.168.1.1 dev eth0
192.168.1.0/24 dev eth0  proto kernel  scope link  src 192.168.1.205
root@webtest:~# ping google.com
ping: unknown host google.com
root@webtest:~# ping facebook.com
ping: unknown host facebook.com
root@webtest:~#

Please refrain from posting images, text is better. Best regards. — maulinglawns, Nov 15 '16 at 11:52
Yes, please, they only make it harder to read your question. — maulinglawns, Nov 15 '16 at 11:54

score 5 · Accepted Answer · answered Nov 15 '16 at 11:33

5

Your broadcast address should be 192.168.1.255, not 192.168.1.1.

answered Nov 15 '16 at 11:33

Johan Myréen

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Does that require a shutdown? Or restarting the network is enough? – Ismael Miguel Nov 15 '16 at 11:36
@Johan Myréen Might be a stupid question, but do we **need** a `broadcast` entry? I only have `address`, `netmask` and `gateway` in my `/etc/network/interfaces` and it works fine! – maulinglawns Nov 15 '16 at 11:45
Sadly, it didn't fix it. There's no internet on it. Maybe I screwed something? I've updated the question anyway. For a good measure, I've edited the file `/etc/network/interfaces` and rebooted the machine. – Ismael Miguel Nov 15 '16 at 11:51
I would say you have made progress. The route is in place, but now you have a DNS problem. Is `/etc/resolv.conf` ok? – Johan Myréen Nov 15 '16 at 12:42
It is showing me this: http://pastebin.com/bkfS9MT9 (vodafonemobile.cpe is the address of the configuration page used by the router) – Ismael Miguel Nov 15 '16 at 13:12
Could you try `ping 8.8.8.8` or `traceroute 8.8.8.8`? – Johan Myréen Nov 15 '16 at 13:45
@JohanMyréen Weirdly, that works. I can ping it with a ping of ~72ms. – Ismael Miguel Nov 15 '16 at 15:22
This confirms that your internet connection is probably perfectly fine, but your DNS is not set up correctly. Are you sure 192.168.1.254 is the correct address of your name server? – Johan Myréen Nov 15 '16 at 15:32
@JohanMyréen It isn't. That's the old gateway. The new one is 192.168.1.1. – Ismael Miguel Nov 15 '16 at 15:36
Your old router apparently also functioned as a name resolver. You will have to edit `/etc/resolv.conf` and add the IP address of your new name server, which is not necessarily to address of your new router. – Johan Myréen Nov 15 '16 at 19:25
@JohanMyréen I'm so sorry for taking so long to answer. I didn't get the notification of the comment. Yes, editing the file `/etc/resolv.conf` and changing every instance of `192.168.1.254` to `192.168.1.1` solved it. I've marked your answer as accepted. – Ismael Miguel Nov 21 '16 at 09:44

score 1 · Answer 2 · answered Nov 16 '16 at 22:46

1

Since your "Edit 1" comments, you would notice that route -n now shows a default gateway. Having ping replying with unknown host may just be related to your DNS configuration. Try ping-ing IPs instead.

Note: in your /etc/network/interfaces, the allow-hotplug eth0 may not be necessary.

answered Nov 16 '16 at 22:46

SYN

2,793
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It actually was a mix of your answer and Johan Myréen's answer. Which includes a bit of yours. I've upvoted it. – Ismael Miguel Nov 21 '16 at 09:45

score 0 · Answer 3 · answered Nov 15 '16 at 11:41

0

From configuration you have done on ip and netmask, Assuming your subnet is /24. Then you broadcast will be 192.168.1.255

answered Nov 15 '16 at 11:41

suhas

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1

That is exactly what @Johan Myréen said five minutes ago... – maulinglawns Nov 15 '16 at 11:42

Can't change the default gateway with static IP

Edit 1:

3 Answers3