eth0 fixed IP. eth1 DHCP gateway. Need access to eth0

rn_ · 08-28-2009, 12:14 PM

Quote:

Originally Posted by fopetesl

[code]~$
~$ sudo traceroute eth0
sudo: traceroute: command not found

try:

Code:

sudo /usr/sbin/traceroute 192.168.1.6

(note also: use the ip address not eth0 for the traceroute command)

fopetesl · 08-28-2009, 12:20 PM

I found this:

Code:

:~$ tracepath eth0
gethostbyname: Host name lookup failure

... any help?

rn_ · 08-28-2009, 01:48 PM

Quote:

Originally Posted by fopetesl

I found this:

Code:

:~$ tracepath eth0
gethostbyname: Host name lookup failure

... any help?

you could use tracepath ... however, even for this you need to specify the ip of the destination:

use: tracepath 192.168.1.6

zhjim · 08-31-2009, 03:10 AM

Hold your horses

We are begining to mix up things. In the start the OP wanted to have eth1 to connect to the external device. And now we get him to use eth0

Best bet is (like evilted suggested) to realy start anew. You seem to rush it a bit.
My approach would be.

1.) Get everything in the shape before you started expanding your network.
Means: Have eth1 to be able to connect to 192.168.1.6 (i read as it was like this. You sure know better).
2.) Note down all of the routes and network configurations
Means: ifconfig (not -a cause this prints all available even if down. check man ifconfig)
route -n (use -n here cause then you will not see the mystic avatar "christravel". -n for numbers only.
3.) Have someone (us?) think about how to setup the routes to the same network through two nics.
4.) Insert eth0
5.) Have it configured (through dhcp)
6.) Aply the route settings from step 3

Tell me what you think

zhjim · 08-31-2009, 03:16 AM

Quote:

Originally Posted by fopetesl

Code:

 route
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.1.0     *               255.255.255.0   U     0      0        0 eth1
default         2WIRE133        0.0.0.0         UG    0      0        0 eth1

and can connect to the Net, (as you see).
BTW, why do I see 192.168.1.0?

I turn the question and ask why dont you see 192.168.1.0 255.255.255.0.
Routes are multiple ways to other IP's so 192.168.1.0 points to all the IP's within the mask 255.255.255.0. There are maths do be done which IP's you can reach through this. But here its easy you can reach all the IP from 192.168.1.1 - 192.168.1.254. (The other two ips are the so called network and broadcast ip's).

http://tldp.org/HOWTO/NET3-4-HOWTO.html is a good howto to get some of this basic knowledge. Might be a bit to big.

(While rereading this it sounds a bit rude but is really ment as a helper. Also its not all that well put...)

Cheers Zhjim

fopetesl · 09-01-2009, 12:17 PM

and getting nowhere. I removed both NICs, removed settings from /etc/network/interfaces and rebooted after enabling eth0.
Set it up as 192.168.1.20 and enabled it. Works as before - just fine.
Then I added eth1 and set it up as DHCP and that works, (you're reading this?).
Now, again, I've lost eth0

Code:

 cat /etc/network/interfaces
# 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 192.168.1.20
netmask 255.255.255.0
broadcast 192.168.1.255
network 192.168.1.0
gateway 192.168.1.6


iface eth1 inet dhcp

auto eth1

but my route is now trashed

Code:

 route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.1.0     0.0.0.0         255.255.255.0   U     0      0        0 eth1
0.0.0.0         192.168.1.1     0.0.0.0         UG    0      0        0 eth1

trying to set up a route for eth0 now fails

Code:

 route add -net 192.168.1.6/24 gw 192.168.1.20 dev eth0 up
Usage: inet_route...,

I've RTFMd til my eyes glaze over but nothing else seems to work

I tried "target" nad every combination I could get any handle on. But nada.
I also note that I'm supposed to set "static route to the gateway" first but couldn't decipher just how to.

BTW, /etc/network/interfaces doesn't do what its supposed to do. I have to set manually to get eth0 'up'

zhjim · 09-02-2009, 01:48 AM

Bummer.

Anyways we somehow have a clear starting point now.
I think I found the typo you have in

Code:

route add -net 192.168.1.6/24 gw 192.168.1.20 dev eth0 up

there is an up to much

Code:

route add -net 192.168.1.6/24 gw 192.168.1.20 dev eth0

Should do the trick.

I'd say were are not far away from the solution. I would delete all the routes beside the default gateway

Code:

0.0.0.0         192.168.1.1     0.0.0.0         UG    0      0        0 eth1

Then add the route to 192.168.1.6 through eth0

Try to connect to 192.168.1.6. If this is fine were one step further

I dug up a link on the debian site. Problem is it is presented to me in german... But should be fine with a browser set to english as default language.

Code:

http://www.us.debian.org/doc/manuals/debian-reference/ch-gateway.de.html#s-net-high

fopetesl · 09-02-2009, 06:28 AM

Quote:

Originally Posted by zhjim

Bummer.

Code:

http://www.us.debian.org/doc/manuals/debian-reference/ch-gateway.de.html#s-net-high

Thanks zhjim for sticking with me but things aren't any better yet. Firefox will translate the site but I can only print out the first page and it says page 1 of 1. Tried all ways to get around that. Failure

If I try cut and paste into an editor it pastes in German!
With my mental faculties it would help greatly if I could sit down and study. Oh, well, as you aptly say, "Bummer".

P.S. Why do I have to enable eth0 manually (or through Settings->Network)?
Surely ../network/interfaces should do that?

Back later....

zhjim · 09-02-2009, 07:13 AM

Quote:

Originally Posted by fopetesl

P.S. Why do I have to enable eth0 manually (or through Settings->Network)?
Surely ../network/interfaces should do that?

Just a matter of used-to-it-ness. I always manuall make my way and then put it into config and/or script files.
/etc/network/interfaces is just the configuration file. Which gets read by /etc/init.d/network. So when ever you change things in ...interfaces you can see if its alright with the system by doing
/etc/init.d/network restart.

Bad luck on the translation it seems. I followed this path from debian.org->Documentation(main link)->Debian Reference (third one from top)-> then all down to chapter 10.
Anyways where I wanted to get your attention on was this

Code:

face eth0 inet static 
             address 192.168.0.111 
             netmask 255.255.255.0
             gateway 192.168.0.1 
             up route add -net 10.0.0.0 netmask 255.0.0.0 gw 192.168.0.2 dev $IFACE 
             down route del -net 10.0.0.0 netmask 255.0.0.0 gw 192.168.0.2 dev $IFACE 
             up echo Interface $IFACE going up | /usr/bin/logger -t ifup 
             down echo Interface $IFACE Going down | /usr/bin/logger -t ifdown

so when we find the right route and ip settings you can all have this set inside your ...interfaces.

Heres a ...interfaces file I would try. Its a modification of the one you posted.

Code:

# 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 bad guy
iface eth1 inet dhcp
auto eth1
up route del -net 192.168.1.0 mask 255.255.255.0 dev eth1

# The primary network interface

iface eth0 inet static
address 192.168.1.20
netmask 255.255.255.0
broadcast 192.168.1.255
network 192.168.1.0
#gateway 192.168.1.6
up route add -host 192.168.1.6 mask 255.255.255.255 dev eth0

This should leave you with two routes. one to 192.168.1.0/24 network through eth0 and one default route through dev eth1. At least thats my theory

. And In theory you would reach 192.168.1.6 through dev eth0 cause it's your network....
About commenting in the gateway I'm not so sure but would try do it without. Is 192.168.1.6 realy a gateway or just a nother computer. Can the road continue after 192.168.1.6 if not than it's no gateway in strict sense (and common sense?

)

fopetesl · 09-02-2009, 12:37 PM

Sorry zhjim. no go

First I took out both NICs. Rebooted and set ../network/interfaces as per your example.
Then shut down, added eth0 and fired up again.
Success communicating with 192.168.1.6

Then shut down again and added eth1.
Lost eth0 comms again but can ping google.com, etc.
I note that the del -net for eth1 doesn't seem to be working?

FYI: eth0 only connects to the controller at 192.168.1.6. Does not get passed on anywhere else. It's just a dumb controller that does what its instructed, (most of the time!).

ifconfig:

Code:

 ifconfig
eth0      Link encap:Ethernet  HWaddr 00:30:BD:70:34:12
          inet addr:192.168.1.20  Bcast:192.168.1.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)
          Interrupt:11 Base address:0xe000

eth1      Link encap:Ethernet  HWaddr 00:40:63:DE:CF:BF
          inet addr:192.168.1.38  Bcast:192.168.1.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:118 errors:0 dropped:0 overruns:0 frame:0
          TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:7649 (7.4 KiB)  TX bytes:1160 (1.1 KiB)
          Interrupt:10 Base address:0xdc00

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:29 errors:0 dropped:0 overruns:0 frame:0
          TX packets:29 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:141007 (137.7 KiB)  TX bytes:141007 (137.7 KiB)

..etc/network/interfaces:

Code:

# 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

iface eth1 inet dhcp
up route del -net 192.168.1.0 mask 255.255.255.0 dev eth1
auto eth1

# The primary network interface

iface eth0 inet static
address 192.168.1.20
netmask 255.255.255.0
broadcast 192.168.1.255
network 192.168.1.0
#gateway 192.168.1.6
up route add -host 192.168.1.6 mask 255.255.255.255 dev eth0

auto eth0

route:

Code:

192.168.1.0     *               255.255.255.0   U     0      0        0 eth1
192.168.1.0     *               255.255.255.0   U     0      0        0 eth0
default         2WIRE133        0.0.0.0         UG    0      0        0 eth1

tracepath:

Code:

 tracepath 192.168.1.6
 1:  192.168.1.38 (192.168.1.38)                            1.130ms pmtu 1500
 1:  no reply
 2:  no reply

zhjim · 09-04-2009, 02:52 AM

Judging from your route command the del route does not work indeed. Or with a slight chance it gets readded when eth0 comes up.
Anyways. Try a route del 192.168.1.0 mask 255.255.255.0 dev eth1 to get rid of the route over eth1.

Another thing might be this thread
http://www.linuxquestions.org/questi...-links-750617/

it's not realy the same but maybe the solution will work here to or try the link in the last post of above thread. But please first try with just deleting the routes on eth1.

Cheers Zhjim

fopetesl · 09-04-2009, 04:50 AM

Quote:

Originally Posted by zhjim

Judging from your route command the del route does not work indeed. Or with a slight chance it gets readded when eth0 comes up.
Anyways. Try a route del 192.168.1.0 mask 255.255.255.0 dev eth1 to get rid of the route over eth1.

The syntax isn't quite correct but I sorted that but still no go. The "del" command trashed the Internet connection and I still couldn't ping 192.168.1.6.
So I added

Code:

~$ sudo route add -net 192.168.1.6 netmask 255.255.255.255 dev eth0

(it wouldn't accept "-host") which didn't change anything.

Quote:

Another thing might be this thread
http://www.linuxquestions.org/questi...-links-750617/
it's not realy the same but maybe the solution will work here to or try the link in the last post of above thread. Cheers Zhjim

Wow! Zhjim. Black magic to me.

The final link to namespaces looks interesting but how do I know if my kernel will accept these 'new' flags? CLONE_NEWNET, etc.
Where/how to look?

Code:

 uname -r
2.6.17-ck1-almeter

zhjim · 09-04-2009, 05:14 AM

Quote:

Originally Posted by fopetesl

Wow! Zhjim. Black magic to me.

The final link to namespaces looks interesting but how do I know if my kernel will accept these 'new' flags? CLONE_NEWNET, etc.
Where/how to look?

Code:

 uname -r
2.6.17-ck1-almeter

I just skimmed the document with the network namespace and my wand is not very good either

To see if your kernel supports it take a look at http://lxc.sourceforge.net/network/configuration.php. There is a list of patches and kernel options. So to know you just copy'N'paste one of the options "Network namespace support" and grep -i through your current kernel config. If you have a match you are set. Else you would need to compile a new kernel or apply the patches from the page.
But honestly i think this is overkill. I have some time on the weekend and try to recreate your setup. And see what I come up with.

fopetesl · 09-04-2009, 05:19 AM

Thanks, Zhjim. I have a sh*tload of work to wade through today then off on a bread making course for the weekend. Catch up on Monday

zhjim · 09-05-2009, 08:07 AM

This ones a bit long but I think it'll best to follow the ideas behind all this.
Found a solution that worked also this is on debian. It's just about to give every host its own route.

Here are the infos after boot with just one nic iped.

Code:

debian:/home/asdf# ifconfig 
eth0      Link encap:Ethernet  HWaddr 00:04:76:8d:5a:04  
          inet addr:10.200.10.20  Bcast:0.0.0.0  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:10 errors:0 dropped:0 overruns:0 frame:0
          TX packets:69 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:2198 (2.1 KiB)  TX bytes:12081 (11.7 KiB)
          Interrupt:10 Base address:0xaf00 

eth1      Link encap:Ethernet  HWaddr 00:04:76:d1:45:38  
          inet6 addr: fe80::204:76ff:fed1:4538/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:7 errors:0 dropped:0 overruns:0 frame:0
          TX packets:51 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:1042 (1.0 KiB)  TX bytes:8676 (8.4 KiB)
          Interrupt:5 Base address:0x8f80 

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:28 errors:0 dropped:0 overruns:0 frame:0
          TX packets:28 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:1952 (1.9 KiB)  TX bytes:1952 (1.9 KiB)

debian:/home/asdf# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.200.10.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0

can we ping 10.200.10.6?

Code:

debian:/home/asdf# ping 10.200.10.6 -c 2
PING 10.200.10.6 (10.200.10.6) 56(84) bytes of data.
64 bytes from 10.200.10.6: icmp_seq=1 ttl=64 time=4.10 ms
64 bytes from 10.200.10.6: icmp_seq=2 ttl=64 time=0.139 ms

--- 10.200.10.6 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1003ms
rtt min/avg/max/mdev = 0.139/2.123/4.107/1.984 ms

yes we can. now get the connection to the world

Code:

debian:/home/asdf# dhclient eth1
Internet Systems Consortium DHCP Client V3.1.1
Copyright 2004-2008 Internet Systems Consortium.
All rights reserved.
For info, please visit http://www.isc.org/sw/dhcp/

Listening on LPF/eth1/00:04:76:d1:45:38
Sending on   LPF/eth1/00:04:76:d1:45:38
Sending on   Socket/fallback
DHCPDISCOVER on eth1 to 255.255.255.255 port 67 interval 3
DHCPOFFER from 10.200.10.1
DHCPREQUEST on eth1 to 255.255.255.255 port 67
DHCPACK from 10.200.10.1
bound to 10.200.10.227 -- renewal in 1630 seconds.

debian:/home/asdf# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.200.10.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
10.200.10.0     0.0.0.0         255.255.255.0   U     0      0        0 eth1
0.0.0.0         10.200.10.1     0.0.0.0         UG    0      0        0 eth1

see if we still can ping 10.200.10.6

Code:

debian:/home/asdf# ping 10.200.10.6 -c 2
PING 10.200.10.6 (10.200.10.6) 56(84) bytes of data.
64 bytes from 10.200.10.6: icmp_seq=1 ttl=64 time=3.02 ms
64 bytes from 10.200.10.6: icmp_seq=2 ttl=64 time=0.143 ms

--- 10.200.10.6 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1006ms
rtt min/avg/max/mdev = 0.143/1.585/3.027/1.442 ms

yes. this is diffrent from your setup. You could not ping it.
see if i can ping the world

Code:

debian:/home/asdf# dig ard.de
^C
debian:/home/asdf# cat /etc/resolv.conf 
nameserver 10.200.10.1

debian:/home/asdf# ping ard.de
^C

doh. no go. so we don't need the route to the lan over eth1. but we need the route to our gateway 10.200.10.1

Code:

debian:/home/asdf# route del -net 10.200.10.0/24 dev eth1
debian:/home/asdf# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.200.10.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
0.0.0.0         10.200.10.1     0.0.0.0         UG    0      0        0 eth1

debian:/home/asdf# route add -host 10.200.10.1 dev eth1
debian:/home/asdf# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.200.10.1     0.0.0.0         255.255.255.255 UH    0      0        0 eth1
10.200.10.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
0.0.0.0         10.200.10.1     0.0.0.0         UG    0      0        0 eth1

See if we can get the wan

Code:

debian:/home/asdf# dig ard.de

; <<>> DiG 9.5.1-P1 <<>> ard.de
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 64259
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;ard.de.				IN	A

;; ANSWER SECTION:
ard.de.			3438	IN	A	217.66.32.21

;; Query time: 55 msec
;; SERVER: 10.200.10.1#53(10.200.10.1)
;; WHEN: Sat Sep  5 13:25:31 2009
;; MSG SIZE  rcvd: 40

Jup DNS works. So the rest should also.
okay we have the wan, see if it remains when we kill the lan net

Code:

debian:/home/asdf# route del -net 10.200.10.0/24 dev eth0
debian:/home/asdf# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.200.10.1     0.0.0.0         255.255.255.255 UH    0      0        0 eth1
0.0.0.0         10.200.10.1     0.0.0.0         UG    0      0        0 eth1
debian:/home/asdf# dig ard.de

; <<>> DiG 9.5.1-P1 <<>> ard.de
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 56625
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;ard.de.				IN	A

;; ANSWER SECTION:
ard.de.			3145	IN	A	217.66.32.21

jup it does. now get our 10.200.10.6 host back

Code:

debian:/home/asdf# route add -host 10.200.10.6 dev eth0
debian:/home/asdf# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.200.10.1     0.0.0.0         255.255.255.255 UH    0      0        0 eth1
10.200.10.6     0.0.0.0         255.255.255.255 UH    0      0        0 eth0
0.0.0.0         10.200.10.1     0.0.0.0         UG    0      0        0 eth1
debian:/home/asdf# ping 10.200.10.6
PING 10.200.10.6 (10.200.10.6) 56(84) bytes of data.
64 bytes from 10.200.10.6: icmp_seq=1 ttl=64 time=2.36 ms
^C
--- 10.200.10.6 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 2.363/2.363/2.363/0.000 ms

All set and all working. getting 10.200.10.6 and the web. Okay the rest of the 10.200.10.0/24 net is gone but who cares

This is a route -n that also worked.

Code:

debian:/home/asdf# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.200.10.6     0.0.0.0         255.255.255.255 UH    0      0        0 eth0
10.200.10.0     0.0.0.0         255.255.255.0   U     0      0        0 eth1
0.0.0.0         10.200.10.1     0.0.0.0         UG    0      0        0 eth1

If you came that far your through

. So I see thats possible to do it but to what availe this is to ubuntu I donnu. The thing I would advise would be.
1.) Kill all routes beside the default route (route del -net 192.168.1.0/24 dev eth0 repeat for eth1)
2.) Add route to 192.168.1.6 (route add -host 192.168.1.6/32 dev eth0)
3.) Add route to 192.168.1.0 (route add -net 192.168.1.0/24 dev eth1)
4.) pray

Maybe I'll find time to setup an ubuntu 6 machine. Thats all I could get. 5 is outdated.

Cheers Zhjim