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Hi Guys,
I have 2 linux box(boxA and boxB), both have 2 net cards .
I set the eth0 as 207.x.x.y (static IP from DSL)
set the eth1 as 192.168.1.1
when I use "route" command,
boxA is OK, I get the following result
---------
Destination Gateway Genmask Flags Metric Ref Use Iface
207.x.x.0 * 255.255.255.0 U 0 0 0 eth0
localnet * 255.255.255.0 U 0 0 0 eth1
loopback * 255.0.0.0 U 0 0 0 lo
default adsl-207-x-x 0.0.0.0 UG 0 0 0 eth0
-----------
But box B is wrong.( I do not connect these 2 boxes to internet
at the same time, I compared these resluts separatedly )
I get the following strange result
(1) I did not set any thing related to 169.254, why I got it?
(2)the default is more strange.
----------------------------
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
207.x.x.0 * 255.255.255.0 U 0 0 0 eth0
192.168.1.0 * 255.255.255.0 U 0 0 0 eth1
169.254.0.0 * 255.255.0.0 U 0 0 0 eth1
127.0.0.0 * 255.0.0.0 U 0 0 0 lo
default 192.168.1.1 0.0.0.0 UG 0 0 0 eth1
----------------------------
who can tell me what's wrong I did on my BoxB?
Thank you in advance!!
Bob
Joerg Sauer
07-24-2004, 11:22 PM
> I get the following strange result
> (1) I did not set any thing related to 169.254, why I got it?
169.254.0.0-169.254.255.255 is a range of private IP addresses that
Microsoft OSes use to assign adresses to interfaces that are configured for
DHCP but were for some reason unable to get an address from a DHCP server.
I have heard that some Linux distros have started to implement that behavior
as well.
So you might have a stale configuration lying around that tries to configure
eth1 through DHCP, fails and then adds the corresponding network to the
routing table.
Then later the interface is configured again (this time the way you want it
to) and you end up with two entries in the routing table.
Of course I'm only making wild (but hopefully educated) guesses but I think
tracing back your startup sequence to spot configuration problems might be
worth a try.
> (2)the default is more strange.
> default 192.168.1.1 0.0.0.0 UG 0 0 0 eth1
This confirms that the system may have been configured for residing on a
LAN, with DHCP and a gateway on the local network.
Do the tools you use to configure your network reflect the parameters the
way you want them? If yes, how to check and fix the configuration really
depends on the distro you're using.
Joerg
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Brett
07-24-2004, 11:25 PM
"Bob" <NoNosend@nospam.Nogo.com> wrote in message news:<tvkYb.1788$_3.29135@typhoon.sonic.net>...
> Hi Guys,
>
> I have 2 linux box(boxA and boxB), both have 2 net cards .
>
> I set the eth0 as 207.x.x.y (static IP from DSL)
> set the eth1 as 192.168.1.1
>
> when I use "route" command,
>
> boxA is OK, I get the following result
>
> ---------
> Destination Gateway Genmask Flags Metric Ref Use Iface
> 207.x.x.0 * 255.255.255.0 U 0 0 0 eth0
> localnet * 255.255.255.0 U 0 0 0 eth1
> loopback * 255.0.0.0 U 0 0 0 lo
> default adsl-207-x-x 0.0.0.0 UG 0 0 0 eth0
> -----------
>
> But box B is wrong.( I do not connect these 2 boxes to internet
> at the same time, I compared these resluts separatedly )
>
> I get the following strange result
>
> (1) I did not set any thing related to 169.254, why I got it?
>
> (2)the default is more strange.
> ----------------------------
> Kernel IP routing table
> Destination Gateway Genmask Flags Metric Ref Use Iface
> 207.x.x.0 * 255.255.255.0 U 0 0 0 eth0
> 192.168.1.0 * 255.255.255.0 U 0 0 0 eth1
> 169.254.0.0 * 255.255.0.0 U 0 0 0 eth1
> 127.0.0.0 * 255.0.0.0 U 0 0 0 lo
> default 192.168.1.1 0.0.0.0 UG 0 0 0 eth1
> ----------------------------
>
> who can tell me what's wrong I did on my BoxB?
>
> Thank you in advance!!
>
> Bob
I had this same exact problem. After some digging around on the net
(and through the initialization scripts) I came up with this -- On Red
Hat 9 in the /etc/sysconfig/network-scripts/ifup there is a line that
looks for the variable NOZEROCONF in the individual ifcfg-* files. If
it is missing, the system will add the route 169.254.0.0 to the
routing table. Look up zeroconf on google, and you'll see that it's
supposed to make it easy for computers to communicate over a network
when there is no DHCP to assign addresses. Anyway, I suggest editing
ALL of your /etc/sysconfig/network-scripts/ifcfg-* files (where * is
eth0, eth1, lo, etc) and adding a new line that reads
NOZEROCONF=yes
That will ensure that when your network comes up, you won't get that
route in your tables. It worked for me. You can also delete the route
without affecting anything.
Brett
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