Ethernet working but can't use the internet?

dan7827 · 5 Oct 2008 at 11:42

Having a slight problem with my cent os box :mad:

I can connect to it through the network and it can ping/nslookup but firefox can't seem to find any sites, same goes for yum & wget. The setup is pretty basic also, pc->router with the gateway & DNS address set to the ip address of the router.

Please help!
Cheers

dan7827 · 5 Oct 2008 at 12:21

Router restarted, same problem.

Ping works fine, here's the output:

Code:

PING google.co.uk (72.14.221.104) 56(84) bytes of data.
64 bytes from google.co.uk (72.14.221.104): icmp_seq=1 ttl=243 time=80.9 ms
64 bytes from google.co.uk (72.14.221.104): icmp_seq=2 ttl=243 time=79.4 ms
64 bytes from google.co.uk (72.14.221.104): icmp_seq=3 ttl=243 time=79.7 ms
64 bytes from google.co.uk (72.14.221.104): icmp_seq=4 ttl=243 time=78.4 ms

--- google.co.uk ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 2999ms
rtt min/avg/max/mdev = 78.445/79.648/80.945/0.894 ms

dan7827 · 5 Oct 2008 at 13:19

Forgot to mention that all the other pcs connecting through the same router are working with no problems (windows), just this one linux pc causing a few headaches. Ping seems to work fine, here it is by ip:

Code:

PING 72.14.221.104 (72.14.221.104) 56(84) bytes of data.
64 bytes from 72.14.221.104: icmp_seq=1 ttl=243 time=79.3 ms
64 bytes from 72.14.221.104: icmp_seq=2 ttl=243 time=78.4 ms
64 bytes from 72.14.221.104: icmp_seq=3 ttl=243 time=81.3 ms
64 bytes from 72.14.221.104: icmp_seq=4 ttl=243 time=77.5 ms

--- 72.14.221.104 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 2999ms
rtt min/avg/max/mdev = 77.548/79.171/81.327/1.394 ms

Also this linux pc is open to the internet for a temp webserver, you should be able to view it here: http://danm.homeip.net/

dan7827 · 5 Oct 2008 at 23:38

Thanks for the links, the solution one seems to be mis-directed now? it mentioned ivp6 but that's disabled, here's the network-script:

Code:

# U.S. Robotics USR997902 10/100/1000 Mbps PCI Network Card
DEVICE=eth1
BOOTPROTO=none
BROADCAST=192.168.0.255
HWADDR=00:C0:49:F2:91:A7
IPADDR=192.168.0.200
NETMASK=255.255.255.0
NETWORK=192.168.0.0
ONBOOT=yes
GATEWAY=192.168.0.1
TYPE=Ethernet
USERCTL=no
IPV6INIT=no
PEERDNS=yes

Just had another mess about and it's still resolving domains but not establishing a connection:

Code:

Resolving www.google.co.uk... 216.239.59.147
Connecting to www.google.co.uk|216.239.59.147|:80...

Time to call it quits before something 'unfortunate' happens to the pc :mad:

dan7827 · 6 Oct 2008 at 08:15

DHCP auto set the gateway and DNS server to 192.168.0.1 but also didn't work. Currently iptables, selinux and ip6tables is disabled, plus ipv6 on the network cards.

I'm at a loss what to try next, one thing that has come to mind is that the two network cards are a bad idea? here's the other config file (this card isn't connected to any network yet):

Code:

# Realtek Semiconductor Co., Ltd. RTL-8139/8139C/8139C+
DEVICE=eth0
BOOTPROTO=none
BROADCAST=192.168.1.255
HWADDR=00:40:F4:62:50:D4
IPADDR=192.168.1.200
NETMASK=255.255.255.0
NETWORK=192.168.1.0
ONBOOT=yes
TYPE=Ethernet
USERCTL=no
IPV6INIT=no
PEERDNS=yes

dan7827 · 6 Oct 2008 at 19:53

This is a standard install of the latest 5.1? cent OS so no crazy mods here.

Here's the dmesg output relating to the eth cards:

Code:

8139cp: 10/100 PCI Ethernet driver v1.2 (Mar 22, 2004)
8139too Fast Ethernet driver 0.9.27
eth0: RealTek RTL8139 at 0xf883a000, 00:40:f4:62:50:d4, IRQ 10
eth0:  Identified 8139 chip type 'RTL-8100B/8139D'
r8169 Gigabit Ethernet driver 2.2LK-NAPI loaded
eth1: RTL8169s/8110s at 0xf888e000, 00:c0:49:f2:91:a7, IRQ 12
eth0: link down
ADDRCONF(NETDEV_UP): eth0: link is not ready
r8169: eth1: link up
eth1: no IPv6 routers present

Thanks fo rthe link, I'm no linux expert so if needed will attempt to check the rest when I get a chance.

EDIT: It seems that the latest (if you can call them that lol) 2004-04-16 drivers for the gigabit card are already in use?

dan7827 · 6 Oct 2008 at 22:38

Thanks for the guidance, had another look at that link and there's not one for centos so will try the guide with the closest commands (ubuntu), although by the looks of it there is one step that doesn't match up to an existing file: /etc/dhcp3/dhclient.conf

dan7827 · 7 Oct 2008 at 19:51

Using either the eth0 or eth1 card with the other disabled does the same thing. resolv.conf showns the nameservers only, after playing around and trying things it currently looks like this:

Code:

nameserver 192.168.0.1
nameserver 69.111.95.106
nameserver 206.196.151.153

I have just had a breakthrough in firefox, if I use nslookup for a domain then copy and paste the ip address it loads fine but any links on the page usually won't work.

I have left the setting in this sort of working state....but what is going on here??? :confused:

dan7827 · 8 Oct 2008 at 12:50

Those nameservers are what are used on other pc on the network fine, I did try some others when I was trying to get something working but now something is actually happening I have left them as is.

When I get back to the pc I will have another look.

dan7827 · 9 Oct 2008 at 23:06

The route output:

Code:

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.0.0     *               255.255.255.0   U     0      0        0 eth0
169.254.0.0     *               255.255.0.0     U     0      0        0 eth0
default         192.168.0.1     0.0.0.0         UG    0      0        0 eth0

hmmm...

dan7827 · 10 Oct 2008 at 12:54

Yep, 192.168.0.1 is set as the gateway & nameservers. Like I say the windows pcs are connecting through the router and work fine, I cant see any difference in the settings that would cause the odd behaviour. :confused:

dan7827 · 6 Nov 2008 at 10:14

Sorry for the delayed response, I have found some time to have another look at this headache problem so here goes.

At the moment I have set it up to use the ethernet card instead of the gigabit card and have disabled the gigabit card. The pc can ping by hostname and ip but tell it to go to resolve a website with wget or firefox and it seems to wait forever (nothing happens), other pcs on the network haven't got any problems so there’s something I'm missing with this setup. Below is the result of trying to get to the root of the problem.

Code:

ifconfig:
---------
eth0      Link encap:Ethernet  HWaddr 00:40:F4:62:50:D4
          inet addr:192.168.0.200  Bcast:192.168.0.255  Mask:255.255.255.0
          inet6 addr: fe80::240:f4ff:fe62:50d4/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:11510 errors:0 dropped:0 overruns:0 frame:0
          TX packets:13357 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:1644799 (1.5 MiB)  TX bytes:7303402 (6.9 MiB)
          Interrupt:10 Base address:0xe000

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:17196 errors:0 dropped:0 overruns:0 frame:0
          TX packets:17196 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:9420371 (8.9 MiB)  TX bytes:9420371 (8.9 MiB)


cat ifcfg-eth0:
---------------
# Realtek Semiconductor Co., Ltd. RTL-8139/8139C/8139C+
DEVICE=eth0
BOOTPROTO=none
BROADCAST=192.168.0.255
HWADDR=00:40:F4:62:50:D4
IPADDR=192.168.0.200
NETMASK=255.255.255.0
NETWORK=192.168.0.0
ONBOOT=yes
TYPE=Ethernet
USERCTL=no
IPV6INIT=no
PEERDNS=yes
GATEWAY=192.168.0.1


nslookup google.co.uk:
----------------------
Server:         192.168.0.1
Address:        192.168.0.1#53
Non-authoritative answer:
Name:   google.co.uk
Address: 72.14.221.104



ping google.co.uk:
------------------
PING google.co.uk (72.14.221.104) 56(84) bytes of data.
64 bytes from google.co.uk (72.14.221.104): icmp_seq=1 ttl=243 time=80.9 ms
64 bytes from google.co.uk (72.14.221.104): icmp_seq=2 ttl=243 time=77.1 ms
--- google.co.uk ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 999ms
rtt min/avg/max/mdev = 77.138/79.061/80.985/1.943 ms



ping 72.14.221.104:
-------------------
PING 72.14.221.104 (72.14.221.104) 56(84) bytes of data.
64 bytes from 72.14.221.104: icmp_seq=1 ttl=243 time=79.9 ms
64 bytes from 72.14.221.104: icmp_seq=2 ttl=243 time=76.5 ms
--- 72.14.221.104 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 999ms
rtt min/avg/max/mdev = 76.583/78.250/79.918/1.690 ms



wget http://www.google.co.uk/intl/en_uk/images/logo.gif:
---------------------------------------------------------
--11:07:55--  http://www.google.co.uk/intl/en_uk/images/logo.gif
Resolving www.google.co.uk... 1.0.0.0
Connecting to www.google.co.uk|1.0.0.0|:80...



dmesg|grep eth:
---------------
eth0: RTL8169s/8110s at 0xf883a000, 00:c0:49:f2:91:a7, IRQ 12
eth1: RealTek RTL8139 at 0xf888e000, 00:40:f4:62:50:d4, IRQ 10
eth1:  Identified 8139 chip type 'RTL-8100B/8139D'
eth0: link up, 100Mbps, full-duplex, lpa 0x41E1
eth0: no IPv6 routers present
eth0: link up, 100Mbps, full-duplex, lpa 0x41E1
eth0: no IPv6 routers present



cat resolv.conf:
----------------
nameserver 192.168.0.1
nameserver 69.111.95.106
nameserver 206.196.151.153



route:
------
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.0.0     *               255.255.255.0   U     0      0        0 eth0
169.254.0.0     *               255.255.0.0     U     0      0        0 eth0
default         mygateway.ed7   0.0.0.0         UG    0      0        0 eth0



chkconfig --list:
-----------------
NetworkManager  0:off   1:off   2:off   3:off   4:off   5:off   6:off
NetworkManagerDispatcher        0:off   1:off   2:off   3:off   4:off   5:off  6:off
acpid           0:off   1:off   2:off   3:on    4:on    5:on    6:off
anacron         0:off   1:off   2:on    3:on    4:on    5:on    6:off
apmd            0:off   1:off   2:on    3:on    4:on    5:off   6:off
atd             0:off   1:off   2:off   3:on    4:on    5:on    6:off
auditd          0:off   1:off   2:on    3:on    4:on    5:on    6:off
autofs          0:off   1:off   2:off   3:on    4:on    5:on    6:off
avahi-daemon    0:off   1:off   2:off   3:on    4:on    5:on    6:off
avahi-dnsconfd  0:off   1:off   2:off   3:off   4:off   5:off   6:off
conman          0:off   1:off   2:off   3:off   4:off   5:off   6:off
cpuspeed        0:off   1:on    2:on    3:on    4:on    5:off   6:off
crond           0:off   1:off   2:on    3:on    4:on    5:on    6:off
cups            0:off   1:off   2:on    3:on    4:on    5:off   6:off
dc_client       0:off   1:off   2:off   3:off   4:off   5:off   6:off
dc_server       0:off   1:off   2:off   3:off   4:off   5:off   6:off
dhcdbd          0:off   1:off   2:off   3:off   4:off   5:off   6:off
dovecot         0:off   1:off   2:off   3:off   4:off   5:off   6:off
firstboot       0:off   1:off   2:off   3:on    4:off   5:off   6:off
gpm             0:off   1:off   2:on    3:on    4:on    5:on    6:off
haldaemon       0:off   1:off   2:off   3:on    4:on    5:on    6:off
hplip           0:off   1:off   2:on    3:on    4:on    5:off   6:off
httpd           0:off   1:off   2:on    3:on    4:off   5:on    6:off
ibmasm          0:off   1:off   2:off   3:off   4:off   5:off   6:off
ip6tables       0:off   1:off   2:off   3:off   4:off   5:off   6:off
ipmi            0:off   1:off   2:off   3:off   4:off   5:off   6:off
iptables        0:off   1:off   2:off   3:off   4:off   5:off   6:off
irda            0:off   1:off   2:off   3:off   4:off   5:off   6:off
irqbalance      0:off   1:off   2:on    3:on    4:on    5:on    6:off
kdump           0:off   1:off   2:off   3:off   4:off   5:off   6:off
kudzu           0:off   1:off   2:off   3:on    4:on    5:on    6:off
lvm2-monitor    0:off   1:on    2:on    3:on    4:on    5:on    6:off
mcstrans        0:off   1:off   2:on    3:on    4:on    5:on    6:off
mdmonitor       0:off   1:off   2:on    3:on    4:on    5:off   6:off
mdmpd           0:off   1:off   2:off   3:off   4:off   5:off   6:off
messagebus      0:off   1:off   2:off   3:on    4:on    5:on    6:off
multipathd      0:off   1:off   2:off   3:off   4:off   5:off   6:off
mysqld          0:off   1:off   2:on    3:on    4:off   5:on    6:off
named           0:off   1:off   2:off   3:off   4:off   5:off   6:off
netconsole      0:off   1:off   2:off   3:off   4:off   5:off   6:off
netfs           0:off   1:off   2:off   3:on    4:on    5:on    6:off
netplugd        0:off   1:off   2:off   3:off   4:off   5:off   6:off
network         0:off   1:off   2:on    3:on    4:on    5:on    6:off
nfs             0:off   1:off   2:off   3:off   4:off   5:off   6:off
nfslock         0:off   1:off   2:off   3:on    4:on    5:on    6:off
nscd            0:off   1:off   2:off   3:off   4:off   5:off   6:off
ntpd            0:off   1:off   2:off   3:off   4:off   5:off   6:off
oddjobd         0:off   1:off   2:off   3:off   4:off   5:off   6:off
pcscd           0:off   1:off   2:on    3:on    4:on    5:off   6:off
portmap         0:off   1:off   2:off   3:on    4:on    5:on    6:off
psacct          0:off   1:off   2:off   3:off   4:off   5:off   6:off
rdisc           0:off   1:off   2:off   3:off   4:off   5:off   6:off
readahead_early 0:off   1:off   2:on    3:on    4:on    5:on    6:off
readahead_later 0:off   1:off   2:off   3:off   4:off   5:on    6:off
restorecond     0:off   1:off   2:on    3:on    4:on    5:on    6:off
rpcgssd         0:off   1:off   2:off   3:on    4:on    5:on    6:off
rpcidmapd       0:off   1:off   2:off   3:on    4:on    5:on    6:off
rpcsvcgssd      0:off   1:off   2:off   3:off   4:off   5:off   6:off
rwhod           0:off   1:off   2:off   3:off   4:off   5:off   6:off
saslauthd       0:off   1:off   2:off   3:off   4:off   5:off   6:off
sendmail        0:off   1:off   2:on    3:on    4:on    5:off   6:off
setroubleshoot  0:off   1:off   2:off   3:on    4:on    5:on    6:off
smartd          0:off   1:off   2:on    3:on    4:on    5:on    6:off
smb             0:off   1:off   2:off   3:off   4:off   5:off   6:off
spamassassin    0:off   1:off   2:off   3:off   4:off   5:off   6:off
squid           0:off   1:off   2:on    3:on    4:off   5:on    6:off
sshd            0:off   1:off   2:on    3:on    4:on    5:on    6:off
syslog          0:off   1:off   2:on    3:on    4:on    5:on    6:off
tux             0:off   1:off   2:off   3:off   4:off   5:off   6:off
vncserver       0:off   1:off   2:on    3:on    4:off   5:on    6:off
vsftpd          0:off   1:off   2:off   3:off   4:off   5:off   6:off
wdaemon         0:off   1:off   2:off   3:off   4:off   5:off   6:off
webmin          0:off   1:off   2:on    3:on    4:on    5:on    6:off
winbind         0:off   1:off   2:off   3:off   4:off   5:off   6:off
wpa_supplicant  0:off   1:off   2:off   3:off   4:off   5:off   6:off
xfs             0:off   1:off   2:on    3:on    4:on    5:on    6:off
xinetd          0:off   1:off   2:off   3:on    4:on    5:on    6:off
ypbind          0:off   1:off   2:off   3:off   4:off   5:off   6:off
yum-updatesd    0:off   1:off   2:on    3:on    4:on    5:on    6:off

xinetd based services:
        chargen-dgram:  off
        chargen-stream: off
        cvs:            off
        daytime-dgram:  off
        daytime-stream: off
        discard-dgram:  off
        discard-stream: off
        echo-dgram:     off
        echo-stream:    off
        eklogin:        off
        ekrb5-telnet:   off
        gssftp:         off
        klogin:         off
        krb5-telnet:    off
        kshell:         off
        rsync:          off
        tcpmux-server:  off
        time-dgram:     off
        time-stream:    off

Sorry for the scary length of the outputs above, hopefully it should show everything in the systems current state. Thanks to anyone who dare to solve this problem!

dan7827 · 6 Nov 2008 at 19:56

Thanks for posting those nameservers, they seem to work but it doesn't explain why none of the others work when they have been tested on other pcson the same network.

Code:

nameserver 208.67.222.222
nameserver 208.67.220.220

Even the router doesn't work on this linux box for dns, weird.

Code:

nameserver 192.168.0.1

Or these

Code:

nameserver 69.111.95.106
nameserver 206.196.151.153

Can anyone explain this???

dan7827 · 8 Nov 2008 at 20:40

That seems to have done the trick.

Thanks a lot!