Ubuntu Networking :: Wired Network Sometimes Doesn't Work
Feb 14, 2011
what is the command to restart the network services? ive forgotten i think it uses -hup switch though. about 1 in 20 boots on my desktop ubuntu system results in the system insisting its no longer on a network yet has a fully functioning network card. a reboot always fixes the issue but that doesnt seem like a long term solution to me. If I ping a neighbouring system I get nothing. (sent packet count increases in ifconfig) If I ping from a neighbouring system back to my desktop I get nothing (no change in packet count) I can bring down and back up the network interface with no results. A sniffer shows the system definitely isnt sending anything out Everything worked previous boot and will work again after a reboot.
My desktop PC has 2 NICs. I have Ubuntu on it since several years, and I remember that both eth0 and eth1 used to work. However, I discovered recently that currently only eth0 works, and eth1 is dead, but I don't know why. It's been a while since I've tried eth1, so I have no idea when exactly it broke. I suspect the problem may be related to the fact that the MAC address is incorrect: it is set to 00:00:00:00:00:00, which seems wrong. But I have no idea how this happened...Any idea what might be wrong and how I can fix it? Here is some output which I think is useful:
Code: peter@cheetah:~$ ifconfig -a eth0 Link encap:Ethernet HWaddr 00:18:f3:68:42:78
I'm having mysterious wired network problem with my Karmic/9.10 machine. It hasn't been in network a while, but now I finally got the cabling done. I can't get the IP from dhcp server (TW-EA510), and static settings doesn't work either. Fresh cabling showed OK 1Gb connection on tester, and win7 laptop works fine. I even tried with long cable though the rooms, but it doesn't help, so it definately isn't the new cabling.
Log from the router after issuing #"dhclient": Feb 16 23:01:43 DHCP SERVER: DHCPDISCOVER from 00:01:29:fb:c5:d1 via br0 Feb 16 23:01:43 DHCP SERVER: DHCP offer to 00:01:29:fb:c5:d1 Feb 16 23:01:49 DHCP SERVER: DHCP request from 00:1b:ea:c8:a0:ba Feb 16 23:01:49 DHCP SERVER: DHCP ack to 00:1b:ea:c8:a0:ba Feb 16 23:01:54 DHCP SERVER: DHCPDISCOVER from 00:01:29:fb:c5:d1 via br0 Feb 16 23:01:54 DHCP SERVER: DHCP offer to 00:01:29:fb:c5:d1 Feb 16 23:02:03 DHCP SERVER: DHCPDISCOVER from 00:01:29:fb:c5:d1 via br0 [Code]....
Motherboard is some old Lanparty with two ethernet ports, NVidia CK804 and Marvell 88E800 rev 13 Gigabit netwok adapters, neither of them works. At least another of them has been worked earlier when I last got it wired. It's been a while, so I'm not sure which one of them and with different router if that matters.
I recently tried out OpenDNS on my wired connection, however after it was slower than faster, I tried going back to the original settings that the connection had (so basically to Automatic DHCP).
For some reason the connection wouldn't connect again. So I thought I'd try deleting that connection and creating a new one, but this still doesn't work. When I try to connect using NetworkManager it just does the 'loading' icon for 30ish seconds then says disconnected.
My wireless still works fine however.
I'd very grateful as i'm worried i've messed up the ethernet port and I need it for when I got University in a couple of weeks
These days I wanted to connect to the internet on my laptop using a wired connection. When I inserted the ethernet cable, I was surprised to see that it doesn't work on Ubuntu 11.04. So I decided to boot into Windows and see if it works or not. And I found that it works without problems on Windows.
I have installed Ubuntu 11.04 using Wubi through Windows 7. It seems to be working but it will not connect to my wired internet connection. It tells me there is no wired connection, when there is. I used sysinfo and its not showing any network adapter or controller. I have a board with nvidia nforce go 430, could it be a driver issue. It works fine in windows though. Tried using a wireless adapter and all is working. But why doesn't the wired ethernet connection work.
I got a problem about network proxy setting. With the graphics setting interface, I set auto proxy with the URL address but it is weird that the setting only work with eth1(wireless), doesn't work with etho(wired). however my wireless driver is always a problem for Linux. i also tried export http_proxy= XXXXX:8080 it still doesn't work at all.
My friend has 2 pcs, one connected to the internet and the other one used to connect (when he had windows installed) to the internet through the first one using internet sharing, now i installed ubuntu on both and the network between them has been created but it wont connect, the internet icons just animates for like a minute then says "wired internet disconnected" in other words it failed to connect.
After i install it i lost my internet connection . i got a message " Wired Network " " you work offline ". i use cable ADSL ,.... my Pc information HP Pavilion 6700 running with both Window 7 & Ubuntu 10.10 note... my network connection work correctly on W7.
i've installed it on my parents old computer, mostly for downloading. But wired internet did work all the time but then i had to reset our router because of some problems and now it doesn't work anymore! But the strange thing is, if i put the cable on my own laptop with windows on it, then it works as normal.
So i guess its some kind of DNS problem, but i'm very new with ubuntu and also not so good with computers. Our network is simple just an modem connected to an router: Sitecome WL-341.
I have two simultaneous active mobile connections through my two mobile phones and USB data cables. Yet I can only send/receive with one connection.Each of the phone modems have a node in /dev, namely ttyACM0 and ttyACM0. So the modems are detected correctly.After setting up two dial-up connections with the two modems I have two ip's. Ifconfig-a confirms this:
ppp0 Link encap:Point-to-Point Protocol inet addr:10.10.219.60 P-t-P:10.6.6.6 Mask:255.255.255.255 UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1
I installed Ubuntu on a machine after erasing everything else and the wireless has never worked. It says that the wireless has already shut down even though it recognizes the wireless network and my other non-linux machines see the network and work fine.
I'm trying to activate a wireless network on an ubuntu server 10.04. The machine has a TPLink PCI wireless card. Card is well recognized, and scanning for wireless connection it finds correctly the essid of the access point in the room. But when I try:
Code: $ sudo iwconfig wlan0 essid "apoint" key s:my_key_8 this error is returned: Code: Error for wireless request "Set Encode" (8B2A) :
SET failed on device wlan0 ; Invalid argument.I looked for similar situations over many forums, and I found that it could be the card doesn't support the encryption type (My AP uses WPA with TKIP). However if I use an ubuntu desktop live CD on the same machine, I can connect witouth any problem with NetworkManager 0.8.
It was working just fine, until the other day I yanked it out. The wireless works just fine on the same router. If I login to a windows 7 instance on this dual boot laptop then the ehternet works just fine. So it's not a hardware, cable or router issue. The card even gets an ip, but I can't connect to the internet.
I added a repo from launchpad to install latest Network Manager and then installed it (version 0.8). Then I decided to rollback to Karmic's version (since 0.8 doesn't work) but failed: I removed the repo from sources.list
Then apt-get udpate Then apt-get clean Then apt-get install network-manager...
But still 0.8 version is downloaded and installed! How can I restore Karmic's version?
I have an Aspire 7741z running Ubuntu 10.04 I just loaded the 32 bit version today, then did the Update manager (398 updates) Before the update everything worked fine. After the update, no wireless. Password & security is correct, all wireless setup is correct. Aside from my network, I do have access to a local hotel (next door) and I can always get into their unsecured guest network, that doesn't work either.
I believe it is the driver since I have loaded Ubintu 10.10 32 bit with the same reaction. It will connect when I put in the live disk, but not from the hard install. output from lspci
For about the past month I have been having a very frustrating problem When I boot the system with the ethernet cable attached it acts as if the cable is unplugged even though the connection light is litWhen I boot the system with the ethernet cable disconnected and wait until it boots all the way to gnome and then plug in the cable everything works fine
I have a pppoe adsl connection. When I disconnect and try to reconnect, network-manager keeps asking for my password. I type it again and again with no success. When I reboot, it works again. On ubuntu, I use pppoeconf and it works well. So on Fedora I made a connection with pppoe-setup but neither ifup nor Code:
pppoe-connect commands work. When I type Code: pppoe-connect , it says Code: /usr/sbin/adsl-start: line 217: 13409 Terminated $CONNECT "$@" > /dev/null 2>&1 . When I type
Ifup ppp0 doesn't work either. However, with exactly the same settings, ubuntu connects to the internet.
I have the problem with my notebook, that, after I used it at work, the network-manager always tries to autoconnect after boot. He has no cable network and so I get the message "not connected" after a while.how to tell the network-manager, not to autoconnect each time?
I bought a switch, connected it to our router,and moved the patch cords to the switch. All but one of the workstations connect & work fine. If I plug the non-connecting wire into my laptop it connects. If I plug the non-connecting wire back into the router,the workstation connects.So...it seems that this particular workstation will only see the address of the old router. It's stuck in there & won't refresh. Two of the PC's & the laptop are running 10.04 (Mint 9 Actually), and one has Windows XP on it.e problem is with one of the 3 10.04 boxesI have tried removing the power cord & MB battery and leaving them out over night.Also cleared the bios. Same results. Connects fine to the old router but will not connect to the new switch.
I recently got a cable modem from Comcast, and connected a Belkin F5D7230-4 wireless router to it, then connected my computer and an Xbox 360 to the router with ethernet cables.
My computer dual-boots Ubuntu 9.10 and Windows 7. In either operating system, the wireless connection is flawless. In Windows, so is the wired connection. But in Ubuntu, there's a lot of trouble with the wired connection -- specifically, while I can connect to the router and to the Internet, and while I can use ping, dig, traceroute, etc., to verify connections to remote hosts, Web browsing, or anything else that uses http, works only for a few Websites, and then only erratically.
I don't believe it is a DNS problem -- testing with ping, dig, etc., demonstrates that, and I have also tried using alternate nameservers. I also don't believe that it is an issue with IPv6, as I've tried the fixes usually suggested, including editing the grub configuration to disable IPv6 support in the kernel and verifying that IPv6 was inactive. I've also tried using local dns servers such as pdns-recursor. None of these things seemed to help.
Also, perhaps unrelated, but disturbing: my computer has locked up a few times while testing the wired connection, and I had to use a hard reset to restart the computer.
Using 10.10 and have a wired connection that according to the system is connected, but when I open a browser I can't connect to any sites. What am I missing here? I can't for the life of me figure this out.