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Old 03-08-2016, 01:29 AM   #1
hardikgohil1988
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ping on-board Ethernet port


I am working on Embedded Board running on Linux 3.2.

There are two on-board Ethernet Ports eth0 and eth1.

I have a requirement to ping eth0 to eth1.

eth0 192.168.82.111
eth1 192.168.82.99

ping -I 192.168.82.111 192.168.82.99

There is a response but doesn’t matter whether eth0---eth1 connected or not.

How to make this work ?
 
Old 03-08-2016, 01:50 AM   #2
zhjim
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You don't have to make it work, as it allready does. If you did not block it with iptables or alike connections on the same machine will work. Like walking from the kitchen to the bathroom will work if no doors are locked.

What you are really up to?
 
Old 03-08-2016, 01:52 AM   #3
OregonJim
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Quote:
Originally Posted by hardikgohil1988 View Post
eth0 192.168.82.111
eth1 192.168.82.99

ping -I 192.168.82.111 192.168.82.99

How to make this work ?
You have two separate interfaces, but they are configured for the same subnet - 192.168.82.x. I don't understand how this would even be routable, unless I'm missing something here...
 
Old 03-08-2016, 02:08 AM   #4
zhjim
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You can route things with a bit of magic. Check out the advanced routing guide on the linux documentation program. Also if not applied can lead to some unpredicted behaviour. Like packages going in on eth0 and out of eth1. Thus screwing connections due to wrong IP's and MAC's.
 
Old 03-08-2016, 04:51 PM   #5
jefro
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Use telnet instead.

Actually be sure to change out subnets too.
 
Old 03-09-2016, 02:37 AM   #6
zhjim
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Why do you prefer telnet over gopher?
 
Old 03-09-2016, 02:51 PM   #7
jefro
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I prefer telnet over ping for this rather useless test. Ping isn't a very good diag tool in my thinking. When onboard nic's are tested sometimes the ip stack actually fools us.
 
Old 03-10-2016, 01:47 AM   #8
zhjim
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Maybe traceroute come in handy.
 
Old 03-14-2016, 06:00 PM   #9
sundialsvcs
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I'm not quite sure what you expected to happen, but it superficially seems to me that you are never asking the ping request to "actually leave the box." Therefore, indeed it would not matter whether an Ethernet cable were plugged-in to the interface or not. If you attempt to ping one address, which is "this box," from another address which is also "this box," then the traffic never has to leave the computer ... and so, it never does.
 
Old 03-21-2016, 03:21 AM   #10
hardikgohil1988
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Quote:
Originally Posted by zhjim View Post
You don't have to make it work, as it allready does. If you did not block it with iptables or alike connections on the same machine will work. Like walking from the kitchen to the bathroom will work if no doors are locked.

What you are really up to?
cannot ping

I have connected eth0<----->eth1 using cable

root@CPU7001:~ ip route
default via 192.168.82.251 dev eth0
192.168.2.0/24 dev eth0 proto kernel scope link src 192.168.2.1
192.168.82.0/24 dev eth0 proto kernel scope link src 192.168.82.111
192.168.82.0/24 dev eth1 proto kernel scope link src 192.168.82.99
 
  


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