[SOLVED] Network has stopped working

[HoaniP]

I am running Mageia 4. with all recent updates installed. I am beginning to wonder if this is a hardware problem.

I access the internet through a Linksys BEFSR41(I know it's getting on a bit) router, which is connected to a Motorola SB5100 Cable Modem, supplied by the cable company. Recently, the computer began taking a long time to connect to the router: the three lights on the router would blink on and off slowly, at the same time, until eventually, it would connect.

A couple of days ago, it stopped connecting. Now the lights on the router just keep blinking, but I can't connect. I have tried turning everything off, then on again, reconfiguring and reconnecting the network, all with no result. I tried to communicate with the router, via Firefox, but get the message "Unable to connect". I have also changed cables, but nothing. Finally, I have checked the back of the computer, and found that, where the ethernet cable plugs into the computer, there is no flashing light to show that there is a connection.

I have other devices, which use this router, and they are performing fine.

My motherboard is a Gigabyte GA-MA78LMT-S2, purchased in May 2011.

Can anyone help me fix the problem, please? or do I need a new motherboard?

Thank you.

[doktor5000]

Easiest thing, did you check if the cable computer > router is faulty?

Otherwise, please post the output of the following commands:

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/sbin/ifconfig -a
netstat -ni
netstat -rn

Please also post the IP adresse of the router.

[HoaniP]

Thank you for your help.

I have tried three separate cables, including two which I borrowed from other working devices, so I know they're OK.

Here is the output:

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[papa@localhost ~]$ /sbin/ifconfig -a
enp2s0    Link encap:Ethernet  HWaddr 1C:6F:65:FF:95:62 
          UP 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)

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:65536  Metric:1
          RX packets:526 errors:0 dropped:0 overruns:0 frame:0
          TX packets:526 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:55792 (54.4 KiB)  TX bytes:55792 (54.4 KiB)

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[papa@localhost ~]$ netstat -ni
Kernel Interface table
Iface       MTU Met    RX-OK RX-ERR RX-DRP RX-OVR    TX-OK TX-ERR TX-DRP TX-OVR Flg
enp2s0     1500   0        0      0      0      0        0      0      0      0 BMU
lo        65536   0      526      0      0      0      526      0      0      0 LRU

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[papa@localhost ~]$ netstat -rn
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
[papa@localhost ~]$

Because the computer won't communicate with the router, I can't check the router's current IP address, but in the past I have always used 192.168.1.1, and that has worked.

Thank you.

[Ken-Bergen]

Have you tried switching the cable to one of the ports where you say other devices can connect?

[doktor5000]

Please next time use code tags as explained in ftp://ftp5.gwdg.de/pub/linux/mandriva/m ... e_tags.ogv

Well, currently your ethernet interface has not received or transmitted any packet at all, and you routing table is completely empty - hence you'll not be able to connect to your router. Or maybe that's because you ran the commands as user.

Can you please show the output as root of

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netstat -rn
ping -c4 192.168.1.1
ping -c4 8.8.8.8
cat /etc/sysconfig/network-scripts/ifcfg-enp2s0

[HoaniP]

Thank you. I've looked several times at the link you supplied, and can't understand what it means in terms of this conversation. There is no sound track.

The output is:

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[papa@localhost ~]$ su
Password:
[root@localhost papa]# netstat -rn
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface

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[root@localhost papa]# ping -c4 192.168.1.1
connect: Network is unreachable
[root@localhost papa]# ping -c4 8.8.8.8
connect: Network is unreachable

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[root@localhost papa]# cat /etc/sysconfig/network-scripts/ifcfg-enp2s0
DEVICE=enp2s0
BOOTPROTO=dhcp
ONBOOT=yes
METRIC=5
MII_NOT_SUPPORTED=no
USERCTL=no
RESOLV_MODS=no
LINK_DETECTION_DELAY=6
IPV6INIT=no
IPV6TO4INIT=no
ACCOUNTING=no
DHCP_CLIENT=dhclient
NEEDHOSTNAME=no
PEERDNS=yes
PEERYP=yes
PEERNTPD=no
[root@localhost papa]#

I hope this helps.

[HoaniP]

Ken, thanks for your help, too.

Yes. I've tried all the combinations of cables and ports. I've also tried plugging the cable directly into the modem, with no success.

Although I've been using Linux since about 1998, I remain ignorant of how it all works. Fortunately, I tend to write things down, so I can go back and see what worked and what didn't. I am also very grateful to all you fine people, who have helped me keep on going.

[doktor5000]

Thank you. I've looked several times at the link you supplied, and can't understand what it means in terms of this conversation. There is no sound track.

No problem. For this forum, when posting console output or log excerpts, please use the forum editors functionality to wrap those sections in code tags, That's what the short video tries to explain I've added those to your previous posts, you can edit them to see what it should look like.

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[root@localhost papa]# netstat -rn
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface

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[root@localhost papa]# ping -c4 192.168.1.1
connect: Network is unreachable
[root@localhost papa]# ping -c4 8.8.8.8
connect: Network is unreachable

Just as mentioned - your routing table is empty, your system has no route to the default gateway (your router) so you cannot access anything.
This network connection is set to DHCP, that means it should receive that information from your router. Seems the problem is with your router. You could check the DHCP settings of your router or at first try to simply power-cycle it. For the DHCP settings, have a look at http://support.linksys.com/en-us/suppor ... 1/download

The other option is to assign a static IP adress configuration, but that may lead to conflicts the next time one of your other network devices gets a different IP adress.

[jiml8]

The other option is to assign a static IP adress configuration, but that may lead to conflicts the next time one of your other network devices gets a different IP adress.

...which might not work anyway, if the router has failed...

Would also pay to check the router's settings and make sure dhcp is turned on in the router.

[doktor5000]

...which might not work anyway, if the router has failed...

Well, in that case it doesn't matter if you configure DHCP or static

[HoaniP]

Thank you all for your help. Problem solved by a trip to the shop to buy a new router, which is up and running with no problems.

It's interesting that my wireless router could talk to it, but my desktop could not, nor could my laptop when I tried it. Anyway, I now have a nice new router for the next 15 years.

Doktor5000, I'll now see if I can edit my previous posts.

Thanks again.

[HoaniP]

Thank you. I see they've all been done.

What does the code process do?

[doktor5000]

No problem. For this forum, when posting console output or log excerpts, please use the forum editors functionality to wrap those sections in code tags, That's what the short video tries to explain I've added those to your previous posts, you can edit them to see what it should look like.

[jiml8]

It's interesting that my wireless router could talk to it, but my desktop could not, nor could my laptop when I tried it. Anyway, I now have a nice new router for the next 15 years.

You probably had one or more LAN ports die on the router. I've seen that kind of problem many more than one time. I've had the port in my workstation die, a couple of motherboards ago. I just slapped a pci NIC into the box and kept on going.