[SOLVED] unable activating eth0

windstory · 09-23-2010, 12:33 AM

My box is centos x86 5.4.

I changed lan card and tried to enable eth0 with command "ifconfig eth0 up", but not worked.

Code:

[root:localhost:~]# ifconfig eth0 up
[root:localhost:~]# ifconfig
eth0      Link encap:Ethernet  HWaddr 08:00:27:9A:7B:6F
          inet6 addr: fe80::a00:27ff:fe9a:7b6f/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:34 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:0 (0.0 b)  TX bytes:7276 (7.1 KiB)

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:4335 errors:0 dropped:0 overruns:0 frame:0
          TX packets:4335 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:5417372 (5.1 MiB)  TX bytes:5417372 (5.1 MiB)

Pleaase let me know how to enable eth0 and see "inet4 address".

Thanks in advance.

prayag_pjs · 09-23-2010, 12:39 AM

Hi,

Please let us know if your network has dhcp server.

you get ipaddress from dhcp server or you have to do it manually?

do this:
Run as root

Code:

system-config-network

Double click on ethO and see that
Activate Device when Computer starts id Checked

(here you can give static ip or configure it to get ip from dhcp)

also disable firewall and selinux

leejohnli · 09-23-2010, 12:53 AM

"dhclient eth0" if it is dynamically assigned address.

windstory · 09-23-2010, 02:14 AM

About dhcp, I got these results.

Quote:

[root:localhost:~]# service dhcpd start
starting dhcpd: [failed]
[root:localhost:~]# dhclient eth0
Internet Systems Consortium DHCP Client V3.0.5-RedHat
Copyright 2004-2006 Internet Systems Consortium.
All rights reserved.
For info, please visit http://www.isc.org/sw/dhcp/

Listening on LPF/eth0/08:00:27:9a:7b:6f
Sending on LPF/eth0/08:00:27:9a:7b:6f
Sending on Socket/fallback
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 5
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 10
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 11
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 12
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 8
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 15
No DHCPOFFERS received.
No working leases in persistent database - sleeping

vinaytp · 09-23-2010, 02:23 AM

Quote:

Originally Posted by windstory

About dhcp, I got these results.

DHCP server is the one which assigns IP address, gateway, netmask , DNS entries etc to your machine.

Please check weather DHCP Server is configured properly. Because you are getting No DHCPOFFERS received. as error. You have told that you have changed the LAN card. So MAC address might have got changed.

Change your old MAC address entry in DHCP server to new one.

Paste your /etc/dhcp.conf configuration file contents here.

windstory · 09-23-2010, 02:29 AM

This is "/etc/dhcp.conf".

Quote:

authoritative;
include "/etc/rndc.key";
# Server configuration:

server-identifier server;
ddns-domainname "best.dyndns.org.";
ddns-rev-domainname "in-addr.arpa.";
ddns-update-style interim;
ddns-updates on;
ignore client-updates;

# This is the communication zone
zone best.dyndns.org. {
primary 127.0.0.1;
key rndckey;
}
default-lease-time 21600; # 6 hours
max-lease-time 43200; # 12 hours

# Client configuration:
option domain-name "best.dyndns.org.";
option ip-forwarding off;
subnet 192.168.0.0 netmask 255.255.255.0 {
range 192.168.0.100 192.168.0.200;
option routers 192.168.0.1; # default gateway
option subnet-mask 255.255.255.0;
option broadcast-address 192.168.0.255;
option domain-name-servers 192.168.0.1;
zone 0.168.192.in-addr.arpa. {
primary 192.168.0.4;
key rndckey;
}
zone localdomain. {
primary 192.168.0.4;
key rndckey;
}
}

prayag_pjs · 09-23-2010, 03:02 AM

hi,

What are you trying to do?
You need ip to your system or want to configure dhcp server?
From dhcp server you will get ip?
You dont need to configure your system as dhcp server to get ip on your own system.
From some one get the details of how you get ip's to other system on network ...is it manually set or you get it through dhcp?

vinaytp · 09-23-2010, 03:12 AM

Dear windstory,

I did not ask you DHCP configuration file of your local system. I asked DHCP configuration of DHCP server in the network.

You have to worry about DHCP if you are getting IP from DHCP server. Else you can assign static ip address manually and check for connectivity
.

This will come to your help.

http://www.centos.org/docs/5/html/De...rk-config.html

jmc1987 · 09-23-2010, 03:38 AM

You are posting info to run a dhcp server. What they (above) are asking how do you connect to a network. Do you connect to a dhcp server with a dhcp client (which pulls IP from a dhcp server).

What does your

/etc/sysconfig/network-scripts/ifcfg-eth0

look like Post it please and put xx on the last to sets of your externel ip if ou are configured with it to keep it private.

windstory · 09-23-2010, 07:00 AM

I added ip to "/etc/sysconfig/network-scripts/ifcfg-eth0", but same result.

Quote:

DEVICE=eth0
BOOTPROTO=dhcp
ONBOOT=yes
HWADDR=08:00:27:4ha:7b:3f
TYPE=Ethernet
IPADDR=192.168.0.4
NETMASK=255.255.255.0

vinaytp · 09-23-2010, 07:06 AM

Quote:

Originally Posted by windstory

I added ip to "/etc/sysconfig/network-scripts/ifcfg-eth0", but same result.

First confirm how are you getting IP address. DHCP or manually assigning the IP (static)?

If your BOOTPROTO is dhcp then you do not have to assign IP and Netmask explicitly.

What is your default gateway ? Add it to GATEWAY= and restart network service

Make changes this way.

Code:

DEVICE=eth0
BOOTPROTO=static
ONBOOT=yes
HWADDR=08:00:27:4ha:7b:3f
TYPE=Ethernet
IPADDR=192.168.0.4
NETMASK=255.255.255.0 
GATEWAY=

Code:

# /sbin/service network restart

windstory · 09-24-2010, 06:45 PM

vinaytp/

I added GATEWAY like this, but same result.

Quote:

DEVICE=eth0
BOOTPROTO=static
ONBOOT=yes
HWADDR=08:00:27:4ha:7b:3f
TYPE=Ethernet
IPADDR=192.168.0.4
NETMASK=255.255.255.0
GATEWAY=192.168.0.1

Quote:

[root:localhost:~]# ifconfig
eth0 Link encap:Ethernet HWaddr 08:00:27:4ha:7b:3f
inet6 addr: fe80::a00:27ff:fe9a:7b6f/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:16 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 b) TX bytes:3352 (3.2 KiB)

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:1888 errors:0 dropped:0 overruns:0 frame:0
TX packets:1888 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:2789480 (2.6 MiB) TX bytes:2789480 (2.6 MiB)

vinaytp · 09-25-2010, 01:10 PM

Quote:

Originally Posted by windstory

vinaytp/

I added GATEWAY like this, but same result.

Hi,

What does following command shows ? Please paste the output here.

Code:

cat /etc/sysconfig/network

Make sure NETWORKING=yes in the above output.

windstory · 09-27-2010, 03:50 AM

Quote:

Originally Posted by vinaytp

Hi,

What does following command shows ? Please paste the output here.

Code:

cat /etc/sysconfig/network

Make sure NETWORKING=yes in the above output.

The result of "cat /etc/sysconfig/network" is here.

Quote:

DOMAINNAME=master
NETWORKING=yes
HOSTNAME=master
FORWARD_IPV4=false

vinaytp · 09-27-2010, 04:08 AM

Quote:

Originally Posted by windstory

The result of "cat /etc/sysconfig/network" is here.

Could you please tell us how you managed to resolve the issue ?