'Network is unreachable'

[dausua]

Hi,

I have been working with my Raspi for a few weeks now, and I've come across a problem.

The ethernet port seems to have stopped working. It does not want to connect to my mac or router, and I cannot diagnose the problem properly.
All the lights are on: FDX, LNK and 10M

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$ ip addr

reveals that there is no IP address for the ethernet, despite it being up.
output is:

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2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether b8……… brd ff:ff:ff………

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ping 192.168.2.1

reveals

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connect: Network is unreachable

The raspi boots fine, and I have reflashed the same image I started with before on the SD card, but it comes up with the same problem.

Previously I had it plugged directly by ethernet to my Mac, but now I've got it plugged into a wired router, and it's exactly the same problem.

How can I solve this? Any help is greatly appreciated

[SirLagz]

try running ifdown eth0 && ifup eth0 and see if it gets an IP address
Otherwise, paste the stuff it outputs when you do that.

[abishur]

have you set a ip address manually?

what do you have in /etc/network/interfaces

[dausua]

try running ifdown eth0 && ifup eth0 and see if it gets an IP address
Otherwise, paste the stuff it outputs when you do that.

No IP address:

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$ sudo ifdown eth0 && ifup eth0
Internet Systems Consortium DHCP Client 4.2.2
Copyright blah blah blah
…
Listening on LPF/eth0/b8:27:eb…
Sending on LPF/eth0/b8:27:eb…
Sending on Socket/fallback
ifup: failed to open statefile /run/network/ifstate: Permission denied

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$ ip addr
1: lo: <LOOPBACK blah blah blah
…
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
     link/ether b8:27… brd ff:ff:ff:…

Apologies couldn't be bothered typing all the useless stuff out.

[Joe Schmoe]

This illustrates well what's really wrong with the "sudo mentality".

The fact that it doesn't chain. I.e.,

sudo command1 && command 2

doesn't do what you expect it to.

OTOH:

sudo bash
command1 && command2

does work as expected.

[bgirardot]

Joe is saying your command:

sudo ifdown eth0 && ifup eth0

will not work, so you need to do:

sudo ifdown eth0 && sudo ifup eth0

or

sudo bash
ifdown eth0 && ifup eth0

but the second command in what you put in failed due to not being sudo/root

[jojopi]

This illustrates well what's really wrong with the "sudo mentality".

Do you dislike at, nice, nohup, strace, time, chrt, ionice, taskset too?

[SirLagz]

try running ifdown eth0 && ifup eth0 and see if it gets an IP address
Otherwise, paste the stuff it outputs when you do that.

No IP address:

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$ sudo ifdown eth0 && ifup eth0
Internet Systems Consortium DHCP Client 4.2.2
Copyright blah blah blah
…
Listening on LPF/eth0/b8:27:eb…
Sending on LPF/eth0/b8:27:eb…
Sending on Socket/fallback
ifup: failed to open statefile /run/network/ifstate: Permission denied

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$ ip addr
1: lo: <LOOPBACK blah blah blah
…
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
     link/ether b8:27… brd ff:ff:ff:…

Apologies couldn't be bothered typing all the useless stuff out.

Paste the output of
sudo ifdown eth0 && sudo ifup eth0

[dausua]

Thanks - sudo

ifdown eth0 && sudo ifup eth0

helped me diagnose the problem. DHCPDISCOVER was requesting an ip address, and then failing. This was due to the fact that I had it plugged into a switch where there was no DHCP server, and for some reason my Mac was not switching the ethernet over and acting as DHCP server when plugged into it. So, it was my Mac's fault and not the Raspberry... should have known it.

Many thanks for your help everyone. Now I can get back to Csound.

[rocketero]

seems like there has not been an answer to this issue so far, last post was Nov 1 last year.

I get the following answer to:

sudo ifdown eth0 && ifup eth0
ifdown: eth0 interface not configured
ifup: failed to open statefile /run/network/ifstate: Permission denied

during the boot process I see this messages:

19.683026] CIFS:VFS: Error connecting to socket. Aborting operation.

I also see other messages down when I type: dmesg | more command:
21.726980] smsc95xx: 1-1.1:1.0: eth0 link up; 100Mbps, full duplex, lpa 0x45E1

I have to report on this message that the cable I'm using is fine, as I have a PC and it connects OK to the 4port ethernet box and it gets an IP address through DHCP. But the RPI doesn't connect.

Also the light gets green in the 4port ethernet box when the RJ45 cable is connected to the RPI meaning there is continuity and the cable is OK.

[rocketero]

somehow I'm now getting an IP address, kinda weird. I however still see some messages during boot process saying: Network is unreachable. and at the end of the boot process it gives an IP address from the router box through DHCP.

[SirLagz]

seems like there has not been an answer to this issue so far, last post was Nov 1 last year.

I get the following answer to:

sudo ifdown eth0 && ifup eth0
ifdown: eth0 interface not configured
ifup: failed to open statefile /run/network/ifstate: Permission denied

during the boot process I see this messages:

19.683026] CIFS:VFS: Error connecting to socket. Aborting operation.

I also see other messages down when I type: dmesg | more command:
21.726980] smsc95xx: 1-1.1:1.0: eth0 link up; 100Mbps, full duplex, lpa 0x45E1

I have to report on this message that the cable I'm using is fine, as I have a PC and it connects OK to the 4port ethernet box and it gets an IP address through DHCP. But the RPI doesn't connect.

Also the light gets green in the 4port ethernet box when the RJ45 cable is connected to the RPI meaning there is continuity and the cable is OK.

keep in mind, sudo only applies to the first command when doing

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sudo ifdown eth0 && ifup eth0

for sudo to work properly in that case you need to run it this way

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sudo ifdown eth0 && sudo ifup eth0