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Old 04-05-2001, 06:59 AM   #1
cotzcar
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Registered: Apr 2001
Location: New Brunswick
Posts: 2

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Angry net down - destination host unreachable


Hello!

Yesterday morning, out of the black my server went bezerk.

Kernel is: 2.2.17 OS: RH 6.2

The ifconfig of this "ill "pc is:
inet addr: 64.5.215.178 Bcast: 64.5.215.191 Mask: 255.255.255.240
RX packets: 0 for all
TX packets:0 errors:807 dropped:0 overruns:0 carrier:1614
collisions:13719 txqueuen:100 Interrupt:11 Base address:0xb800

So, nobody was around this box when it went offline. Here is how the network looks like.
I have a gateway: 64.5.215.134 and 64.5.215.177. From this machine I have a hub with only one machine on it ( the "ill' pc. )
Now. When I ping the gateway from outside I can get to 64.5.215.177.

Pinging anything from the "ill" pc ( 64.5.215.178 ) I get:
From 64.5.215.178 : Destination Host Unreachable

dmesg gives me: ne2k-pci.c: PCI NE2000 clone 'RealTek RTL--8029' at I/O 0xb800, IRQ 11
eth0: RealTek-8029 found at 0xb800, IRQ 11, 00:C0:A8:50B:F7

Now, when I replaced the NIC, even if selected to unconfigure the NIC, when I boot up with another card it will still show Rel-Tek card in...

Thank You All!! I hope to get some help.


[Edited by cotzcar on 04-05-2001 at 01:43 PM]
 
Old 04-06-2001, 09:25 AM   #2
raz
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Registered: Apr 2001
Location: London
Posts: 408

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Cotzcar,

First thing to do its to check the binding of the cards.
do an ifconfig -a and see if eth0 is UP.
i.e, should say.
inet addr:64.5.215.178 Bcast:64.5.215.191 Mask:255.255.255.240
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

Second thing to do is some RPC checking.
See if the linux box can ping it's localhost and then see if it can ping its own IP 64.5.215.178, it will use suns remote Proc call to do this, helping you to find out if the cards are working.

Now I'm confused as to which system gave back the ICMP error.

You must go to a system that's going to use the router to hop to the Linux box, don't ping out from the Linux box.

If the error is a "Destination Unreachable" error then no route to the host was found in the routing table of the router or routing table is corrupt.

If the error is a "Destination Host Unreachable" from this other system to the Linux box, then the router is getting no response to the datagram from the host in its routing table. (either way the router is giving you the clue)
i.e NIC Card or Network connection/cable error.

Also why do you split the network up into virtual groups of 14 nodes with the subnet mask ?

I would suggest changing the subnet mask from it's current 28bit setting to a 24bit setting. ie your virtual network only allows 14 hosts up to .191 "change to 255.255.255.0" so the rest of the subnet is accessible for testing purposes.

Also check your static routers with.
netstat -r
Should see:
Destination Gateway Genmask Flags
0.0.0.0 64.5.215.177 255.255.255.0 UG etc..

U = up
G = gateway

what does yours say ?

/Raz
 
Old 04-12-2001, 10:08 AM   #3
cotzcar
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Registered: Apr 2001
Location: New Brunswick
Posts: 2

Original Poster
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Smile

Ok,
First: Thank you for you reply Razbot!!

Solution to my problem:
1- Change the NIC card
2- Recompile the kernel: the kernel was compiled Static so this is why it was not recognizind the other cards!!!
3- At recompile time make sure the good! image is used and not the old one...
4- It worked!
 
  


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