Need guidance on solving 'no network connectivity' problem

[askrieger]

Re: Need guidance on solving 'no network connectivity' problem

The weirdest thing about your ethtool output is "link detected: no". This usually means that your internet cable is unplugged, but in this case we know that your cable is not unplugged because if it were you couldn't obtain internet access in any OS! I'm also surprised by the lack of any "link partner advertised link modes". This means your machine thinks it is saying "Here I am. This is what I can do, what can you do?", but it isn't talking to anybody who can tell it which communication mode to use. This another indication that linux thinks your cable is unplugged. Your OS thinks it is sending out a greeting and nobody is responding. I'm beginning to think that your hardware is not being recognised appropriately.

I'm also somewhat surprised that you seem to be using twisted pair rather than cat5 cable. Is this true, or is it just another factor in your system's confusion about your hardware?

I'm also surprised that you don't have an inet address in your "ifconfig -a" output. Was this a transcription error on your part, or was this section of that line actually missing from your output? If it was missing, that's obviously part of your problem, your computer doesn't know it's own address (in Linux), so it can't tell anyone else how to reach it, which makes your failure to see any activity at all on eth0 more understandable, if still baffling. Do you have a file called "/etc/resolv.conf"? If so, it should have at least 4 lines. One saying something like "domain my.isp.com"; another saying "search my.isp.com"; and two lines of internet addresses saying "nameserver xxx.yyy.zzz.nnn" with numbers between 0 and 255. This file should have been set up automatically when you installed Linux

[XEyedBear]

Re: Need guidance on solving 'no network connectivity' problem

The "service" commands need a "sudo" prefix:

sudo service networking stop

sudo service networking start

Since you have tried everything else, what does

sudo ifup eth0

return?

This command returns the error message:

"unknown interface eth0=eth0"

I should also add that the command 'sudo service networking stop' results in the rror messahe:
"stop: Unknown instance:"

I could agree with this statement if the colon after the word 'stop' was elided, transforming the statement from an announcement to a suggestion. But other than that, it mean nothing to me.

[XEyedBear]

Re: Need guidance on solving 'no network connectivity' problem

The weirdest thing about your ethtool output is "link detected: no". This usually means that your internet cable is unplugged, but in this case we know that your cable is not unplugged because if it were you couldn't obtain internet access in any OS! I'm also surprised by the lack of any "link partner advertised link modes". This means your machine thinks it is saying "Here I am. This is what I can do, what can you do?", but it isn't talking to anybody who can tell it which communication mode to use. This another indication that linux thinks your cable is unplugged. Your OS thinks it is sending out a greeting and nobody is responding. I'm beginning to think that your hardware is not being recognised appropriately.

I'm also somewhat surprised that you seem to be using twisted pair rather than cat5 cable. Is this true, or is it just another factor in your system's confusion about your hardware?


I'm also surprised that you don't have an inet address in your "ifconfig -a" output. Was this a transcription error on your part, or was this section of that line actually missing from your output? If it was missing, that's obviously part of your problem, your computer doesn't know it's own address (in Linux), so it can't tell anyone else how to reach it, which makes your failure to see any activity at all on eth0 more understandable, if still baffling. Do you have a file called "/etc/resolv.conf"? If so, it should have at least 4 lines. One saying something like "domain my.isp.com"; another saying "search my.isp.com"; and two lines of internet addresses saying "nameserver xxx.yyy.zzz.nnn" with numbers between 0 and 255. This file should have been set up automatically when you installed Linux

Sorry about the delay in replying: aside from other things, I just could not find this thread in the forum. A search for all posts by myself yielded no result. After some days of searching, I finally found where the thread I started some days ago is.

As far as I can tell, I'm using a Cat 5 cable; that's certainly what is printed on the cable. I have tried 3 diferent cables; all work when Windows is booted; none work when Kubuntu is booted.


The output from the 'ifconfig -a' was not retyped; I copy/pasted using a plain text file that I could then read from within Windows. I don't think anyhting was lost in this process.


Yes, there is a file 'etc/resolv.conf'; it's contents are (retyped):
"# Generated by NetworkManager"

[XEyedBear]

Re: Need guidance on solving 'no network connectivity' problem

According to the output of ifconfig -a you card is properly recognized by the kernel and now we just need to get it working. Whaen you run sudo ifup eth0 if you get any error messages we need to see those.

OK, as I (erroneously) posted a few minutes ago, the more accurately reported error message is:
"Ignoring unknown interface eth0=eth0"

[vinnywright]

Re: Need guidance on solving 'no network connectivity' problem

tony@ADVENT:~$ ifconfig -a
eth0 Link encap:Ethernet HWaddr 00:15:f2:44:25:00
BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
Interrupt:17

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:149 errors:0 dropped:0 overruns:0 frame:0
TX packets:149 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:13388 (13.3 KB) TX bytes:13388 (13.3 KB)

the section on eth0 should ahve a line like

UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

but dose not so the interface isent getting turned on.

what dose

vinny@desktop:~$ cat /var/lib/NetworkManager/NetworkManager.state

show ?

mine looks like this

vinny@desktop:~$ cat /var/lib/NetworkManager/NetworkManager.state

[main]
NetworkingEnabled=true
WirelessEnabled=true
WWANEnabled=true

this is the file that @Liquidator wanted you to remove......as it get's messed up by suspending the machine to RAM some times.

you would have needed to append sudo to the command he gave you.......

sudo rm /var/lib/NetworkManager/NetworkManager.state

VINNY

[XEyedBear]

Re: Need guidance on solving 'no network connectivity' problem

The command "cat /var/lib/NetworkManager/NetworkManger.state" gives the following result:

[main]
NetworkingEnabled=false
WirelesssEnabled=true
WWANEnabled=true

[dibl]

Re: Need guidance on solving 'no network connectivity' problem

Referring to Reply #12, open a Konsole, and enter

sudo service networking start

and then post those lengthy errors here for review.

[XEyedBear]

Re: Need guidance on solving 'no network connectivity' problem

Referring to Reply #12, open a Konsole, and enter

sudo service networking start

and then post those lengthy errors here for review.

This seems to be a diffreent command than before - it has the expression 'sudo' in front of it, so it is a different command and has different results:

"networking stop/waiting"

[vinnywright]

Re: Need guidance on solving 'no network connectivity' problem

The command "cat /var/lib/NetworkManager/NetworkManger.state" gives the following result:

[main]
NetworkingEnabled=false
WirelesssEnabled=true
WWANEnabled=true

this is A problem .......... maybe not the main prob but a problem none the less.
do as @Liquidator suggested and

sudo rm /var/lib/NetworkManager/NetworkManager.state

then restart the box.

VINNY

[XEyedBear]

Re: Need guidance on solving 'no network connectivity' problem

OK; the suggested file (NetworkManager.state) has been
removed, the system restarted and Firefox loaded.

There is not connectivity to my LAN or to the Internet.

[Snowhog]

Re: Need guidance on solving 'no network connectivity' problem

Network connectivity works when booted into Windows, but not when booted into Linux.

There is a thread here in KFN somewhere, that referenced the network controller being 'turned off' when Windows was shutdown - a software switch setting. Is this possibly the case here?

When booted in Windows, check the Network settings for anything that might indicate that the controller can be turned off when shutting down. If such exists, change the setting so that the controller is left 'on' when shutting down.

[askrieger]

Re: Need guidance on solving 'no network connectivity' problem

In researching your problem, I just learned that "ASUS a8v" is not sufficient to characterize the contents of your motherboard. There are, at least, four ASUS a8v motherboards, with different components "on board", (as it were). Do you have an a8v Deluxe, an a8v-MX, an a8v-VM, an a8v-E, or something else?

Yet another question: In the bad old days, some motherboards were delivered without hardware acoustic modem chips, instead they had "winmodems". Instead, old M$ operating systems taught their acoustic chips to sing "beeep, bip,bip, beeep, bip etc." into their telephones. This was very popular with companies manufacturing low cost motherboards. Nowadays, silicon is cheap, so this shortcut is out of fashion, but there might be some other hack going around that allows M$ to lock in hardware manufacturers.

Somewhat later: I did find some negative comments about the ASUS NX1001 network adapter not playing well with 2.6 Linux kernels. So if your mobo has an NX1001 network chip, that might be your problem.

[XEyedBear]

Re: Need guidance on solving 'no network connectivity' problem

In researching your problem, I just learned that "ASUS a8v" is not sufficient to characterize the contents of your motherboard. There are, at least, four ASUS a8v motherboards, with different components "on board", (as it were). Do you have an a8v Deluxe, an a8v-MX, an a8v-VM, an a8v-E, or something else?

Yet another question: In the bad old days, some motherboards were delivered without hardware acoustic modem chips, instead they had "winmodems". Instead, old M$ operating systems taught their acoustic chips to sing "beeep, bip,bip, beeep, bip etc." into their telephones. This was very popular with companies manufacturing low cost motherboards. Nowadays, silicon is cheap, so this shortcut is out of fashion, but there might be some other hack going around that allows M$ to lock in hardware manufacturers.

Somewhat later: I did find some negative comments about the ASUS NX1001 network adapter not playing well with 2.6 Linux kernels. So if your mobo has an NX1001 network chip, that might be your problem.

Ahem, beg pardon. It is indeed an Asus A8V. This is the lowest cost member of the A8V series. But it doesn't make much difference: firstly, I think all the A8V series have the same on-board Marvell Gigabit lan capability and, secondly, this part of the motherboard specification has not changed in the last 6 weeks that I have been having the problem.

The only thing that obviously has changed is Kubuntu - through its process of automatic updates. Windows, of course, does the same thing and continues to provide me with network connectivity - even during the latest epedemic of Windows security updates.

Without having a water-tight proof, all my suspicions are that a Kubuntu update has fatally wounded my system. Bearing in mind that Linux is incompatible with people like me, who just want to use a computer (in contrast to being a bit-level expert on every one of its few hundred million points of potential failure), I am unable to figure what has failed or how to fix it.

The key application I want - secure on-line banking, free from the risk of using 'built for criminals' Windows - is the one application that is not available to me. I can live without the LAN connectivity: USB read/writes still work.

If I have to resort to a re-install of the operating system then this will be sufficient proof to me that Linux is not the right system to use - but, since I can't afford the Jobsian religious experience, I don't know what is the right system.

[XEyedBear]

Re: Need guidance on solving 'no network connectivity' problem

Network connectivity works when booted into Windows, but not when booted into Linux.

There is a thread here in KFN somewhere, that referenced the network controller being 'turned off' when Windows was shutdown - a software switch setting. Is this possibly the case here?

When booted in Windows, check the Network settings for anything that might indicate that the controller can be turned off when shutting down. If such exists, change the setting so that the controller is left 'on' when shutting down.

There are 2 obscure settings for the Network adapter, accessible through Windows device manager: 'Wake from Shutdown' (which was disabled) and 'Allow windows to power this device off to save power' (which was enabled). I have reversed the state of both these settings. However, since these settings have never been changed since I built the system (more than1 year ago) and since Kubuntu was operating fine with these settings until 6 weeks ago, I doubted if this change would make any difference.

It didn't.

[Detonate]

Re: Need guidance on solving 'no network connectivity' problem

This is one of those situations whre I would recommend removing network manager and run your internet connection without it.

http://kubuntuforums.net/forums/inde...opic=3100052.0