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My host machine has an IP 10.116.65.150 and my secondary machine is part of the same network.

(( I did connect my laptop to the same ethernet and switch link as I had connected my secondary machine to.. AND gave the same IP configuration of 10.116.65.8 netmask 255.255.255.0 ))

Obviously ping didnt work.

Although I am able to ping, 10.116.65.8 from the same machine (basically a loopback), I am not even able to ping the gateway (10.116.65.1)

I DID add a default gateway and checked the IP routing table and it looks like this:

Destination     Gateway         Genmask         Flags Metric Ref    Use Iface

default         10.116.65.1     0.0.0.0         UG    0      0        0 fm2-mac5
10.116.65.0     *               255.255.255.0   U     0      0        0 fm2-mac5

I suspect something IS wrong with my IP table.

And further when I connect any other system to that specific port, I find that the Kernel IP routing table gets updated with entries automatically, which doesn't happen in the system that I have.

The kernel is built with the NETFILTER switched off. So iptables is disabled as well.

The machine can ping/boot from a network (from u boot), so I eliminated the possibility of a hardware issue. I also verified the kernel log and the ethtool log and everything seems fine (ethtool said that the Link is up and active). I am able to ping myself(10.116.65.8) and hence can I conclude that IP configuration issue is fine and the routing table is the culprit??

Thanks in advance.

EDIT: Host machine (10.116.65.150)

eth1 Link encap:Ethernet HWaddr c8:9c:dc:a4:9d:da
inet addr:10.116.65.150 Bcast:10.116.65.255 Mask:255.255.255.0 inet6 addr: fe80::ca9c:dcff:fea4:9dda/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:1751485 errors:0 dropped:0 overruns:0 frame:0 TX packets:1014657 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:2393305594 (2.3 GB) TX bytes:77107636 (77.1 MB) Interrupt:20 Memory:fe500000-fe520000 route Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface default 10.116.65.1 0.0.0.0 UG 0 0 0 eth1 10.116.65.0 * 255.255.255.0 U 1 0 0 eth1 169.154.0.0 * 255.255.0.0 U 1000 0 0 eth1

PINGs gateway and machine

Secondary Machine (10.116.65.8): root@t4240qds:~# ifconfig fm2-mac5 10.116.65.8 netmask 255.255.255.0 up

fm2-mac5 Link encap:Ethernet HWaddr 00:04:9f:02:e5:a7
inet addr:10.116.65.8 Bcast:10.116.65.255 Mask:255.255.255.0 inet6 addr: fe80::204:9fff:fe02:e5a7/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:3 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 B) TX bytes:238 (238.0 B) Memory:fe5e8000-fe5e8fff

root@t4240qds:~# route add default gw 10.116.65.1 root@t4240qds:~# route Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface default 10.116.65.1 0.0.0.0 UG 0 0 0 fm2-mac5 10.116.65.0 * 255.255.255.0 U 0 0 0 fm2-mac5

PINGs nothing and not detected in the network

Laptop (10.116.65.8 - same as Secondary machine):

sudo ifconfig eth0 10.116.65.8 netmask 255.255.255.0 up

eth0 Link encap:Ethernet HWaddr 24:b6:fd:31:63:a2
inet addr:10.116.65.8 Bcast:10.116.65.255 Mask:255.255.255.0 inet6 addr: fe80::26b6:fdff:fe31:63a2/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:12176 errors:0 dropped:1 overruns:0 frame:0 TX packets:11463 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:12518972 (12.5 MB) TX bytes:1716704 (1.7 MB)

Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 10.116.65.0 * 255.255.255.0 U 0 0 0 eth0

PINGs the universe (even without the gateway), like a badass!!! AND I wasnt able to get permissions to get the IP routing table in the gateway :( Sorry.

Cheers and Thanks!!

share|improve this question
    
Can you list, for each interface on each system (host, secondary, laptop and "gateway") that interface IP address and netmask, and the system default gateway? (the gateway system will have a default gateway too) –  Slartibartfast Mar 26 at 4:53

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