I think we're getting closer to solving this. On both computers I did as
you said:
arp -s othercomp's_IP othercomp's_hwaddress
Now I try to ping 192.168.0.2 from 192.168.0.1. But I still get no
response. The
action\active lights on both NIC's are blinking. I do the same from
192.168.0.2 but still get
the same nonresponse. However, I let 192.168.0.2 continue to try to ping
and from 192.168.0.1
I execute the command "ping -v 192.168.0.2" This is where it gets wierd.
I still get no
response from 192.168.0.2 but on 192.168.0.1 ping reports that it is
recieving an echo
request from 192.168.0.2. I then try to do the reverse on the other
computer, but it won't work. Only 192.168.0.1 can detect the packets
that are being sent.
192.168.0.2 can't detect 192.168.0.1's echo requests.
Now since 192.168.0.1 can detect echo request's from192.168.0.2, why
isn't it sending an
echo response? When simultaneously pinging both computers 192.168.0.1's
recieved packets
number is steadily increasing while the other computer's number stays
the same. I think a
possible (although strange) explanation would be that 192.168.0.2 can
only send but not
recieve packets, while 192.168.0.1 is acting normally. 192.168.0.2sends
the echo request,
then 192.168.0.1 responds, but 192.168.0.2 never recieves it. Now vice
versa. 192.168.0.1
sends an echo request, 192.168.0.2 never recieves it which explains the
low number of packets
recieved and why "ping -v 192.168.0.1" doesn't produce the same results
as trying to ping
from the other computer. Although I could be wrong about all this and
would love your
opinions and suggestions.
Any more Ideas? I included some info from my 192.168.0.1 computer
for reference. The
other computer is configured similarly, except with appropriate IP's and
HWaddresses. I hope
I have made myself understandable, but if you have a question about my
explanation, please
ask.
Nmagination:~# ifconfig
eth0 Link encap:Ethernet HWaddr 00:A0:CC:3D:10:CA
inet addr:192.168.0.1 Bcast:192.168.0.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:255 errors:0 dropped:0 overruns:0 frame:0
TX packets:318 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
Interrupt:5 Base address:0xb000
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:3924 Metric:1
RX packets:8 errors:0 dropped:0 overruns:0 frame:0
TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
Nmagination:~# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use
Iface
127.0.0.1 * 255.255.255.255 UH 0 0 0
lo
192.168.0.0 * 255.255.255.0 U 0 0 0
eth0
192.168.0.0 * 255.255.255.0 U 0 0 0
eth0
Nmagination:/etc/init.d# less network
#! /bin/sh
ifconfig lo 127.0.0.1
route add -host 127.0.0.1 lo
ifconfig eth0 192.168.0.1 netmask 255.255.255.0
route add -net 192.168.0.0 netmask 255.255.255.0 eth0
Nmagination:/etc/init.d# arp
Address HWtype HWaddress Flags
Mask Iface
darthpenguin ether 00:A0:CC:3B:22:5E
CM eth0
Dave Brooks wrote:
> I'll have to try this quick, so sorry for my shortness (Im about to leave work ;):
>
> ARP is the language network cards talk before they know IP -- it's how DHCP works.
> A card broadcasts its MAC address (hardware address; 6 octets delimited by colons)
> and asks if any other computer knows who it is or what IP address it should have.
> A DHCP sever picks up on this, and sends it an IP through the ARP protocol.
>
> I dont know exactly why in some instances they cant see each other, but it happens.
>
> Try 'arp -s hostname hw_addr', obviously replacing hostname with the hostname of
> the remote machine and hw_addr with the MAC address. The mac address can be attained
> by executing an ifconfig on the remote machine.
>
> Gotta go,
> Dave
>
> Thus spake Tri,
> >You are absolutely right! I tried to check arp for my NIC's ip and then for the other
> >computer's ip and both returned "no entry". One more question though, how do I remedy
> >this? I have no experience with the arp command, and reading the man page doesn't help.
> >Can you give me the commands? Also i'm curious what arp actually is.
> >
> >Tri
> >
> >Dave Brooks wrote:
> >
> >> Check the arp tables on the machine you know works.
> >> It sounds to me like this might be an arp issue.
> >>
> >> I had an issue at home awhile back where I swapped two computer's
> >> IP addresses on my LAN at home, and suddenly they couldn't talk to
> >> each other anymore, but they can talk to the other computers on the
> >> LAN. This might be whats happening to you, but it may be a little
> >> more tricky to notice since there are only two machines.
> >>
> >> Make sure you get something like this (this was done on the machine
> >> with a 192.168.1.1 address):
> >>
> >> drako:(~)% arp -n 192.168.1.2
> >> ? (192.168.1.2) at 0:40:5:4f:7c:d8
> >>
> >> (Obviously, the syntax would be 'arp [-n] hostname')
> >>
> >> If you get something like this:
> >>
> >> drako:(~)% arp -n 192.168.1.4
> >> 192.168.1.4 (192.168.1.4) -- no entry
> >>
> >> ...you may need to add the MAC address of the NetGear NIC card into your
> >> arp table.
> >>
> >> Godspeed,
> >> Dave
> >> ">dbrooks@comstar.net
> >>
> >> Thus spake Tri,
> >> >No unusual kernel messages
> >> >I set up my card and network like this
> >> >
> >> >ifconfig eth0 192.168.0.1 netmask 255.255.255.0 up
> >> >route add -net 192.168.0.0 netmask 255.255.255.0 eth0
> >> >
> >> >likewise on the other computer but with different IP addresses
> >> >the 2 computers are connected using a crossover cable (varified that it works in
> >> >windoze)
> >> >ifconfig shows what is expected, except that the # number of packets recieved is zero
> >> >compared to the number of packets transmitted which is greater than 0.
> >> >route also shows what is expected.
> >> >Funny thing is that my card seems to try to work. When the module is installed it
> >> >reports everything correctly and even sets the card into full duplex. The transmit
> >> >light on the back even lights up during pinging but I still can't get a response. I
> >> >have tried pinging from both computers with similar results. Maybe it's time to quit?
> >> >
> >> >Tri
> >> >
> >> >Chris Ricker wrote:
> >> >
> >> >> On Thu, 6 Jan 2000, Tri wrote:
> >> >>
> >> >> > I've just tried what you suggested below. The module loads correctly and doesn't
> >> >> > complain. It detects a PNIC chip and everything is honkey dorey until I try to
> >> >> > ping a machine on my network. I get no response from the other machine. I tried
> >> >> > to telnet and it told me that there was no route to host. It's looking dim for
> >> >> > my netgear....
> >> >> >
> >> >>
> >> >> What do the routing tables look like? ifconfig? What are the kernel
> >> >> messages?
> >> >>
> >> >> later,
> >> >> chris
> >> >>
> >> >> --
> >> >> Chris Ricker ">kaboom@gatech.edu
> >> >> ">chris.ricker@genetics.utah.edu
> >> >
> >> >--
> >> >To unsubscribe: mail ">majordomo@ale.org with "unsubscribe ale" in message body.
> >>
> >> --
> >> david a. brooks
> >> ">dbrooks@comstar.net
> >> systems engineer
> >> comstar.net, inc.
> >> voice: .. 770/485-6029
> >> pager: .. 770/213-6133
>
> --
> david a. brooks
> ">dbrooks@comstar.net
> systems engineer
> comstar.net, inc.
> voice: .. 770/485-6029
> pager: .. 770/213-6133
--
To unsubscribe: mail ">majordomo@ale.org with "unsubscribe ale" in message body.