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-   -   "..device eth0 does not seem to be present.." unable to network Redhat (https://www.linuxquestions.org/questions/linux-networking-3/device-eth0-does-not-seem-to-be-present-unable-to-network-redhat-499521/)

osvaldomarques 11-08-2006 06:21 PM

Hi GP00,

Something stinks there. Are the electrical installation properly grounded?

Did your machine works after reset?

From your last post, "Destination unreachable" is a route problem. Enter the command
Code:

route -n
to see what the kernel is understanding. I guess that the PEERDNS is not being honored as you have an static route and this option is used when you get a lease address.

You could reconfigure your machine easily to get the dynamic IP. Just enter
Code:

netconfig
it will show you a dialog box that, when you check the "DHCP" config, it's done. Then,
Code:

service network restart
and you're done.

GP00 11-08-2006 06:25 PM

I'm ready to head home for the day, been here too long.
Just a few mins ago, I came back and reset the computer, then redid the
tail command... I unplugged the cable, there was no message, plugged back in, no message change...

I did the network-restart command thing, then the tail again, but again, this time, unplugging the cable, didn't report it going down. Checking right now to see if the arp has something to do with that sequence of events. nope, ran arp -a then did the tail command thing again, no message changes when unplugged and replugged.

I'm going to head home for the night, hopefully give a go in the morning again

GP00 11-08-2006 06:28 PM

route -n

kernel ip routing table
desintation gateway genmask flags metric ref use iface
aaa.bbb.ccc.0 0.0.0.0 255.255.255.0 u 0 0 0 eth0
169.254.0.0 0.0.0.0 255.255.0.0 u 0 0 0 eth0
0.0.0.0 aaa.bbb.ccc.1 0.0.0.0 ug 0 0 0 eth0


will try the switch to dynamic and restart

GP00 11-08-2006 06:31 PM

issued command, got the funky lores setup screen, checked DHCP

issued network restarting command, okayed the shutdown, setup, and loopback, but

determining ip information for eth0 ... failed

was hoping. now, I'm heading out

osvaldomarques 11-08-2006 06:48 PM

You deserves a good dream this night!!! See you tomorrow.

GP00 11-09-2006 10:09 AM

I reconfigured it for static ip this time again, and reset the newtork service and did the 'route' command again
this time, its the same table as above, but instead of the third line being
0.0.0.0 aaa.bbb.ccc.1 .....
it says
default aaa.bbb.ccc.1 .....

does that mean anything?

And for that matter, what does the route table say - is everything "as it should be" or different from what is expected, therefor, check the xxxxxx file and manually change the ppp.qqq.rrr.sss to ....... type things?

GP00 11-09-2006 10:12 AM

actually, I'm wrong - another change NOW is that the route table has
*
in place of the 0.0.0.0 in the gateway column for the first two entries as well

GP00 11-09-2006 01:54 PM

status update

got bold, got brave, got curious. command ifup eth0 was tossing the RTNETLINK answers: Invalid argument error

Edited the ifup script with echo statements to trace, got through to the ifup-post, then ifup-route, craps out in ifup-route in the handle_file function.
Craps out on this command:

/sbin/ip route add $line

where $line = aaa.bbb.ccc.19/24 via aaa.bbb.ccc.1 dev eth0

so, it seems that the hardware issue itself has been fixed up - though I really don't know if it was the combination of doing, undoing, redoing, reundoing, doing, undoing, and redoing while undoing and the moon was directly overhead, or if the moon was more on the horizon at the time....

osvaldomarques 11-09-2006 03:48 PM

Hi GP00,

I told you yesterday to enter "route -n"; this option show all the address as numbers: "default" means "0.0.0.0" and vice-versa. On the gateway, "*" also means "0.0.0.0", which means "no gateway".

I think this route command of the last post a bit strange as you don't need route into your subnetwork. The ARP protocol should resolve the destinations.

Can you ping to your gateway with and without your route command?

GP00 11-13-2006 12:00 PM

been away for a while - I'm not someone who will abandon a thread and leave the participants in the dark....

pertaining to the arp thing, is that something I'd have to execute EVERY TIME I start the computer in order for the likelyhood of something to work?

As for the error-trackdown in the script, I had repeatedly tested it by running
ifup eth0 over and over, and it seems that it might be that when the system boots it puts that info into the table, then when I rerun it, it is trying to add existing info to the table? Somehow, somewhere, an entry for aaa.bbb.ccc.0 was made to aaa.bbb.ccc.19 and when I changed it to 0, the script no longer craps a message in bootup about an invalid argument, but rather "file exists" at the point now where it is executing the command to add ip route
aaa.bbb.ccc.0/24 via aaaa.bbb.ccc.1 dev eth0

osvaldomarques 11-13-2006 12:42 PM

Hi GP00,

Just after you complete your boot procedure, you should have a routing table as you displayed on your post of 11-08-06, 10:28 PM, if you have the ifcfg-eth0 as you displayed on your post of 11-08-06 09:49 PM.

Having this routing table, you should ping all the aaa.bbb.ccc.xxx net. You should also ping outside this subnet as you have aaa.bbb.ccc.1 as your default gateway.

If you can't do this, you may have one of two problems:
- your physical/electrical link is not working (cable, nic, switch)
- the de2471x driver does not work.

I would suggest you to get another nic, of the popular ones, such as realtek or via, replace and see if your computer enters the network.
This would eliminate the cable and switch problems or would confirm this problem is outside your computer.

If it works with another card, you should contact Red Hat to see if there is some problem with this device driver on the version you are using.

GP00 11-13-2006 02:07 PM

Yeah, I am getting to that point where its time to change the network card again, and hope that all the trouble into locating 'the right driver' will be better this time. I'd feel MUCH better about doing so if I knew what exactly worked last time to suddenly make the card active, because it only seemed that after the nth time rbooting and remaking a change back to an earlier change from an earlier change that hadn't worked, etc, did it suddenly become active.. but, close to the point of trying, yes - got to get another card.

UhhMaybe 05-22-2007 06:34 PM

Seems a replacement PCI Ethernet Card is warranted. Try http://www.pcsurplusonline.com and http://www.outletpc.com for inexpensive hardware. Watch the shipping costs and it will be worth YOUR while. I use 3COM 3c905b cards. Linux Distro's have the drivers included. Setup Networking during the install, reboot, and YOU'RE online. YOUR system has the older Kernel, so this will work for YOU. YOU need to use the tools..."ifconfig -a" and "ifconfig", "lspci", "lsusb", "lsmod", "modprobe", "route -n", "route", "ethtool", and "dig". And the network start and stop commands. And the Eth0 <Eth1, Eth2,etc.> up and down commands.

cmalone_vms 06-04-2009 10:54 AM

HELP!!!
 
I have been in this cold, nosy room for three days, please help. I rebuilt my Red Hat server and unable to connect out to anything. I am need to Linux but I think I have been through the basics. My problems are similiar to the thread above. Please help!


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