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Baryon

Member

Registered: 2011-08-12

Posts: 72

[solved] Network not working (wired, DHCP)

I've just moved house and my internet connection doesn't work. I didn't think I would have to change any settings because it was wired/DHCP before and it is now. The network does work on Windows on the same machine, however. I am struggling to diagnose the problem.

lspci -v:

eth0      Link encap:Ethernet  HWaddr 00:11:25:11:E2:27
          inet6 addr: fe80::211:25ff:fe11:e227/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:12766 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1242 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:839720 (820.0 Kb)  TX bytes:129353 (126.3 Kb)

ip addr show dev eth0:

3: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:11:25:11:e2:27 brd ff:ff:ff:ff:ff:ff
    inet6 fe80::211:25ff:fe11:e227/64 scope link tentative 
       valid_lft forever preferred_lft forever

I am just using the network daemon, but I do have netcfg and ifplugd installed as well (they are not in the daemons array). I thought maybe ifplugd was conflicting somehow, but it fails to stop. I wanted to try renewing the DHCP lease, but the command dhcpd is not found, even though it is definitely installed (and indeed running). The e1000 driver is loaded according to dmesg. Any ideas?

Last edited by Baryon (2011-09-14 15:08:24)

karol

Archivist

Registered: 2009-05-06

Posts: 25,440

Re: [solved] Network not working (wired, DHCP)

What's wrong, can you ping stuff etc? Looks good to me.

BTW, are you sure that's 'lspci -v' output?

Last edited by karol (2011-09-10 14:17:59)

lifeafter2am

Member

From: 127.0.0.1

Registered: 2009-06-10

Posts: 1,332

Re: [solved] Network not working (wired, DHCP)

I've just moved house and my internet connection doesn't work. I didn't think I would have to change any settings because it was wired/DHCP before and it is now. The network does work on Windows on the same machine, however. I am struggling to diagnose the problem.

lspci -v:

eth0      Link encap:Ethernet  HWaddr 00:11:25:11:E2:27
          inet6 addr: fe80::211:25ff:fe11:e227/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:12766 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1242 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:839720 (820.0 Kb)  TX bytes:129353 (126.3 Kb)

ip addr show dev eth0:

3: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:11:25:11:e2:27 brd ff:ff:ff:ff:ff:ff
    inet6 fe80::211:25ff:fe11:e227/64 scope link tentative 
       valid_lft forever preferred_lft forever

I am just using the network daemon, but I do have netcfg and ifplugd installed as well (they are not in the daemons array). I thought maybe ifplugd was conflicting somehow, but it fails to stop. I wanted to try renewing the DHCP lease, but the command dhcpd is not found, even though it is definitely installed (and indeed running). The e1000 driver is loaded according to dmesg. Any ideas?

The command is dhcpcd, which could be why it didn't work.

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Baryon

Member

Registered: 2011-08-12

Posts: 72

Re: [solved] Network not working (wired, DHCP)

What's wrong, can you ping stuff etc? Looks good to me.

BTW, are you sure that's 'lspci -v' output?

No, I can't ping. Pinging an address gives me "unknown host" and pinging an IP gives me "connect: network is unreachable".
That might be another command... hmm, I'll check. Thanks for your reply.

The command is dhcpcd, which could be why it didn't work.

Thanks, I noticed that after a while. And I managed to get it working - until I rebooted. And now I cannot replicate the fix.

I typed:

# ifplugd
# modprobe e1000
# /etc/rc.d/network restart
# ip link set eth0 up
# dhcpcd -k
# dhcpcd -nd

So I added dhcpcd -k eth0; dhcpcd -nd eth0 to /etc/rc.local, but after rebooting, it no longer worked, and I couldn't get it to work. I also tried adding ifplugd to the daemons array and e1000 to the modules array, and still no luck.

The output of dhcpcd -nd:

dhcpcd[7353]: version 5.2.12 starting
dhcpcd[7353]: eth0: using hwaddr 00:11:25:11:e2:27
dhcpcd[7353]: eth0: executing `/usr/lib/dhcpcd/dhcpcd-run-hooks', reason PREINIT
dhcpcd[7353]: eth0: executing `/usr/lib/dhcpcd/dhcpcd-run-hooks', reason CARRIER
dhcpcd[7353]: wlan0: using hwaddr 00:05:4e:49:d4:f4
dhcpcd[7353]: wlan0: executing `/usr/lib/dhcpcd/dhcpcd-run-hooks', reason PREINIT
dhcpcd[7353]: wlan0: executing `/usr/lib/dhcpcd/dhcpcd-run-hooks', reason NOCARRIER
dhcpcd[7353]: eth0: reading lease `/var/lib/dhcpcd/dhcpcd-eth0.lease'
dhcpcd[7353]: eth0: rebinding lease of 188.193.200.157
dhcpcd[7353]: eth0: sending REQUEST (xid 0x4423f403), next in 3.12 seconds
dhcpcd[7353]: wlan0: waiting for carrier
dhcpcd[7353]: eth0: acknowledged 188.193.200.157 from 83.169.184.130
dhcpcd[7353]: eth0: checking for 188.193.200.157
dhcpcd[7353]: eth0: sending ARP probe (1 of 3), next in 1.93 seconds
dhcpcd[7353]: eth0: sending ARP probe (2 of 3), next in 1.04 seconds
dhcpcd[7353]: eth0: sending ARP probe (3 of 3), next in 2.00 seconds
dhcpcd[7353]: eth0: carrier lost
dhcpcd[7353]: eth0: executing `/usr/lib/dhcpcd/dhcpcd-run-hooks', reason NOCARRIER
dhcpcd[7388]: eth0: eth0: MTU restored to 1500
dhcpcd[7353]: eth0: carrier acquired
dhcpcd[7353]: eth0: using hwaddr 00:11:25:11:e2:27
dhcpcd[7353]: eth0: executing `/usr/lib/dhcpcd/dhcpcd-run-hooks', reason CARRIER
dhcpcd[7353]: eth0: reading lease `/var/lib/dhcpcd/dhcpcd-eth0.lease'
dhcpcd[7353]: eth0: rebinding lease of 188.193.200.157
dhcpcd[7353]: eth0: sending REQUEST (xid 0x842a4209), next in 4.73 seconds
dhcpcd[7353]: eth0: acknowledged 188.193.200.157 from 83.169.184.130
dhcpcd[7353]: eth0: checking for 188.193.200.157
dhcpcd[7353]: eth0: sending ARP probe (1 of 3), next in 1.32 seconds
dhcpcd[7353]: eth0: sending ARP probe (2 of 3), next in 1.78 seconds
dhcpcd[7353]: eth0: sending ARP probe (3 of 3), next in 2.00 seconds
dhcpcd[7353]: eth0: carrier lost
dhcpcd[7353]: eth0: executing `/usr/lib/dhcpcd/dhcpcd-run-hooks', reason NOCARRIER
dhcpcd[7437]: eth0: eth0: MTU restored to 1500
dhcpcd[7353]: eth0: carrier acquired
dhcpcd[7353]: eth0: using hwaddr 00:11:25:11:e2:27
dhcpcd[7353]: eth0: executing `/usr/lib/dhcpcd/dhcpcd-run-hooks', reason CARRIER
dhcpcd[7353]: eth0: reading lease `/var/lib/dhcpcd/dhcpcd-eth0.lease'
dhcpcd[7353]: eth0: rebinding lease of 188.193.200.157
dhcpcd[7353]: eth0: sending REQUEST (xid 0x9ba048a6), next in 3.54 seconds
dhcpcd[7353]: eth0: acknowledged 188.193.200.157 from 83.169.184.130
dhcpcd[7353]: eth0: checking for 188.193.200.157
dhcpcd[7353]: eth0: sending ARP probe (1 of 3), next in 1.21 seconds
dhcpcd[7353]: eth0: sending ARP probe (2 of 3), next in 1.74 seconds
dhcpcd[7353]: eth0: sending ARP probe (3 of 3), next in 2.00 seconds
dhcpcd[7353]: eth0: leased 188.193.200.157 for 4235 seconds
dhcpcd[7353]: eth0: adding IP address 188.193.200.157/21
dhcpcd[7353]: eth0: adding route to 188.193.200.0/21
dhcpcd[7353]: eth0: adding default route via 188.193.207.254
dhcpcd[7353]: eth0: writing lease `/var/lib/dhcpcd/dhcpcd-eth0.lease'
dhcpcd[7353]: eth0: executing `/usr/lib/dhcpcd/dhcpcd-run-hooks', reason BOUND
dhcpcd[7476]: eth0: eth0: MTU set to 576
dhcpcd[7353]: forking to background
dhcpcd[7353]: forked to background, child pid 7501

Last edited by Baryon (2011-09-11 09:26:54)

ewaller

Administrator

From: Pasadena, CA

Registered: 2009-07-13

Posts: 20,694

Re: [solved] Network not working (wired, DHCP)

In the earlier ip output, you only had an IPv6 address.  After you ran dhcpcd, it appears you should have an IPv4 address of 188.193.200.157.  Could you verify that with ip addr ??

Also:

dhcpcd[7353]: version 5.2.12 starting
...
dhcpcd[7353]: eth0: executing `/usr/lib/dhcpcd/dhcpcd-run-hooks', reason CARRIER
...
dhcpcd[7353]: wlan0: executing `/usr/lib/dhcpcd/dhcpcd-run-hooks', reason NOCARRIER
...
dhcpcd[7353]: wlan0: waiting for carrier
...
dhcpcd[7353]: eth0: carrier lost
dhcpcd[7353]: eth0: executing `/usr/lib/dhcpcd/dhcpcd-run-hooks', reason NOCARRIER
...
dhcpcd[7353]: eth0: carrier acquired
...dhcpcd[7353]: eth0: executing `/usr/lib/dhcpcd/dhcpcd-run-hooks', reason CARRIER
...
dhcpcd[7353]: eth0: carrier lost
dhcpcd[7353]: eth0: executing `/usr/lib/dhcpcd/dhcpcd-run-hooks', reason NOCARRIER
...
dhcpcd[7353]: eth0: executing `/usr/lib/dhcpcd/dhcpcd-run-hooks', reason CARRIER

Methinks you have a hardware problem.  The carrier on a wired connection generally does not behave like that.
If you use an operaing system from the USA's Pacific Northwest, it may work, but does it post notifications of the cable being disconnected, then connected, ..repeat...?
Check your NIC for LEDs that indicate carrier and antivity.  Do they  stay lit, or do they go dark periodically?  Have you tried a different Cable? Do you know the cable length in the walls?  Do you know if it is CAT 3 or CAT 5 cable in the walls? Are you using 100 or 1000 Base-T (1000 uses more pairs)

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Baryon

Member

Registered: 2011-08-12

Posts: 72

Re: [solved] Network not working (wired, DHCP)

Thanks for your reply, but as I said, the connection works absolutely perfectly in Windows on the same machine, so I don't really suspect a hardware problem. Yes, it should be an IPv4 address. I could check the LEDs... I do notice that the link LED on the access point/router flashes on and off when I'm on Linux, but appears to be constant on Windows. Yet it is the same cable and the same laptop. I think it's a CAT5 cable and a Gigabit Ethernet port. It worked fine at home.

Baryon

Member

Registered: 2011-08-12

Posts: 72

Re: [solved] Network not working (wired, DHCP)

I managed to get this working by using dhclient instead of dhcpcd. It was like magic.