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kirim
14th August 2007, 08:42
new to linux, need help on DHCP
i have one machine with two Nic on, eth0 has a public ip and eth1 for DHCP
DHCP installed and able to assign IP address to PCs in my network. Pinging my default gateway on eth1 is not responding or reply ... what seems to be the problem... appreciate any ideas to try:confused:

falko
15th August 2007, 19:25
What's your gateway, eth0 or eth1? What's the output of ifconfig? What's the ping command you used?

kirim
16th August 2007, 01:44
thanks my ifconfig is as follows

root@ienserver:/home/adminim# ifconfig
eth0 Link encap:Ethernet HWaddr 00:17:31:7B:35:02
inet addr:202.43.9.64 Bcast:202.43.9.255 Mask:255.255.255.0
inet6 addr: fe80::217:31ff:fe7b:3502/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:58804 errors:0 dropped:0 overruns:0 frame:6534
TX packets:3171 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:7567275 (7.2 MiB) TX bytes:532504 (520.0 KiB)
Interrupt:19 Base address:0xd000

eth1 Link encap:Ethernet HWaddr 00:08:A1:A3:47:30
inet6 addr: fe80::208:a1ff:fea3:4730/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:40 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 b) TX bytes:4321 (4.2 KiB)
Interrupt:20 Base address:0xc800

eth1:avah Link encap:Ethernet HWaddr 00:08:A1:A3:47:30
inet addr:169.254.5.64 Bcast:169.254.255.255 Mask:255.255.0.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Interrupt:20 Base address:0xc800

:)

falko
16th August 2007, 15:57
What about my other questions?

Your eth1 has an IPv6 address only, no IPv4 address. I think that could be the cause of your problem.

kirim
17th August 2007, 09:01
using ping

eg ping 192.168.0.1

ok how will i enable ipv4 then...please advise cos i really need to get
this going...much thanks

falko
18th August 2007, 12:41
using ping

eg ping 192.168.0.1I don't see that IP address in the output of ifconfig...

ok how will i enable ipv4 then...please advise cos i really need to get
this going...much thanksWhat's in /etc/network/interfaces and /etc/hosts?

kirim
18th August 2007, 22:38
i am using Ubuntu 7.04 Fiesty Fawn
thanks this is my network interfaces
# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
iface eth0 inet static
address 202.43.9.64
netmask 255.255.255.0
gateway 202.43.9.1

# The Local Network for Clients
iface eth1 inet dhcp

And this is my host
127.0.0.1 localhost.localdomain localhost
202.43.9.64 ienserver.matangiake.to ienserver.matangiake.to


# The following lines are desirable for IPv6 capable hosts
#::1 ip6-localhost ip6-loopback
#fe00::0 ip6-localnet
#ff00::0 ip6-mcastprefix
#ff02::1 ip6-allnodes
#ff02::2 ip6-allrouters
#ff02::3 ip6-allhosts
:confused:

falko
19th August 2007, 15:46
Hm... And where does the eth1:avah device come from?

kirim
19th August 2007, 21:59
the eth1:avah device is one of the features in the Network Settings..one for Static, DHCP and Local Zeroconf Network (IPv4 LL) when i selected the Local Zeroconf Network the eth1:avah device appeared as one of the output using ifconfig.... as shown in the previous thread.

I want eth1 to distribute IP to my local network but i cannot. in my network interface conf i configured eth1 with the pool of IPs but still could not work to distribute ips ... any idea.. please advise
thanks

falko
20th August 2007, 19:57
Can you try to assign a static IP to eth1? What's the output of ifconfig then?

kirim
21st August 2007, 11:29
thanks

i put static ips on the eth1 and now the ifconfig output is as follows;

root@ienserver:/home/adminim# ifconfig
eth0 Link encap:Ethernet HWaddr 00:17:31:7B:35:02
inet addr:202.43.9.64 Bcast:202.43.9.255 Mask:255.255.255.0
inet6 addr: fe80::217:31ff:fe7b:3502/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:9915 errors:0 dropped:0 overruns:0 frame:91
TX packets:5759 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:9209914 (8.7 MiB) TX bytes:625554 (610.8 KiB)
Interrupt:19 Base address:0xd000

eth1 Link encap:Ethernet HWaddr 00:08:A1:A3:47:30
inet addr:192.168.0.2 Bcast:192.168.0.255 Mask:255.255.255.0
inet6 addr: fe80::208:a1ff:fea3:4730/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:101 errors:0 dropped:0 overruns:0 frame:0
TX packets:63 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:15652 (15.2 KiB) TX bytes:4008 (3.9 KiB)
Interrupt:20 Base address:0xc800

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:4 errors:0 dropped:0 overruns:0 frame:0
TX packets:4 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:168 (168.0 b) TX bytes:168 (168.0 b)

root@ienserver:/home/adminim#

kirim
22nd August 2007, 05:34
ok..

now my pc can get its ip from the DHCP server but cannot ping my gateway
192.168.0.1 or connect to the internet.

i guess my dhcp is working with the result shown below

root@ienserver:/home/adminim# /etc/init.d/dhcp3-server restart
* Stopping DHCP server dhcpd3 [ OK ]
* Starting DHCP server dhcpd3 [ OK

what should i do to connect my pc to the internet..thanks:)

falko
22nd August 2007, 19:19
Is 192.168.0.1 a system/router of its own?

What's in /etc/network/interfaces now? What's the output of route -nee?

kirim
23rd August 2007, 05:48
out for /etc/network/interfaces is at below;
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
iface eth0 inet static
address 202.43.9.64
netmask 255.255.255.0
gateway 202.43.9.1

# The Local Network for Clients
iface eth1 inet static
address 192.168.0.2
netmask 255.255.255.0
gateway 192.168.0.1

auto eth1

auto eth0
~
"/etc/network/interfaces" 22 lines, 461 characters

output for route -nee is as below;

root@ienserver:/etc/network# route -nee
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface MSS Window irtt
202.43.9.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 0 0 0
192.168.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 0 0 0
169.254.0.0 0.0.0.0 255.255.0.0 U 1000 0 0 eth1 0 0 0
0.0.0.0 202.43.9.1 0.0.0.0 UG 0 0 0 eth0 0 0 0
0.0.0.0 192.168.0.1 0.0.0.0 UG 0 0 0 eth1 0 0 0
root@ienserver:/etc/network#

thaks let me know what to do next...still can not ping my gateway or go on the internet...i got my IPs thou from dhcp....

soroccoheaven
23rd August 2007, 08:23
verify your option router in dhcpd.conf it should be 192.168.0.1;
and see the messasges cat /var/log/messages

and check your ip forwarding status:

In /etc/sysctl.conf make net.ipv4.ip_forward = 1

falko
23rd August 2007, 19:37
Are you sure your gateway has the IP 192.168.0.1?

kirim
23rd August 2007, 23:54
i have done all of the stuff in the last thread and still cannot connect to the internet...

for your info,,,
well, i only have one PC with two NiCs, i don't have a router therefore i use eth0 for my internet connection and i want eth1 for DHCP. The default gateway i am talking about here is the one i put in eth1 and it is the same one on the dhcp.conf as well... eth0 has a public ip and eth1 i use a private ip 192.168.0.0
DHCP is working but cannot ping any ip...
so from here i don't know whether the way i think will work or not for having eth1 distributing ip... i have linux box and my clients are windows will this cause the problem for not accessing the internet. I also have samba installed..

appreciate any idea..
:confused:

soroccoheaven
24th August 2007, 11:23
well.. i am not a GURU ..where did you get this 192.168.0.1 ???....is this IP address given to any of your interface ?..you havent done so ..as you said you are having 2 NIC one with static ip and other from local poool right ?....you gave 192.168.0.2 to 2nd NIC with gateway 192.168.0.1 ..what about this 192.168.0.1 ..any interface having this IP address in network ?....
you can try this and i am sure it will wotk for you ..

Is this done ?..
edit this : /etc/sysctl.conf and make net.ipv4.ip_forward = 1

change the ip address of 2nd NIC to 192.168.0.1 and default gateway 202.43.9.1 on eth1 so in dhcpd.conf you have to define your range from 192.168.0.2 to whatever you need .

and run /etc/init.d/network restart and /etc/init.d/dhcpd restart

verify from cat /var/log/messages

and Finally if isnt working pls post output of this :

/etc/sysconfig/network-scripts/ifcfg-eth0 and
/etc/sysconfig/network-scripts/ifcfg-eth1

Now you should be able to ping all the node as well as internet.