can't ping over crossover cable (get martian source)
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From: chuck smoko on 4 Oct 2009 22:08 Hi, I don't see a RUNNING (i.e. UP BROADCAST RUNNING) on the interface's ifconfig. Below is an ifconfig's eth0 on my system. From my experience, if you don't have RUNNING, you don't have "link". [root(a)drlin001 sbin]# ifconfig eth0 Link encap:Ethernet HWaddr 00:06:5B:ED:39:38 inet addr:10.151.10.58 Bcast:10.151.10.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:426778132 errors:0 dropped:0 overruns:0 frame:0 TX packets:430171885 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:100 RX bytes:381827976 (364.1 MiB) TX bytes:2592226465 (2.4 GiB) Base address:0xcce0 Memory:feb60000-feb80000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:165487055 errors:0 dropped:0 overruns:0 frame:0 TX packets:165487055 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:64638175 (61.6 MiB) TX bytes:64638175 (61.6 MiB) [root(a)drlin001 sbin]# As I can't see your dmesg output, if the interfaces are GIGE, you don't even need a crossover cable. Of all of the ones that I have seen, GIGE Ethernet interfaces generally know how to auto-crossover. If you�re not sure which physical interface is eth0 and which is eth1 (or eth2), run: ethtool -p eth0 5 This blinks the LED on the interface for five seconds without interrupting network traffic. Chuck Smoko The Derfer wrote: > I've got a RHEL 3AS box with a PCI-X network card in it and I've set > that up as such (its ifconfig -a here): > > eth3 Link encap:Ethernet HWaddr 00:0A:5E:7A:E7:33 > inet addr:10.156.30.176 Bcast:10.156.30.255 Mask:255.255.255.0 > UP BROADCAST MULTICAST MTU:1500 Metric:1 > RX packets:527 errors:0 dropped:0 overruns:0 frame:0 > TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 > collisions:0 txqueuelen:1000 > RX bytes:62674 (61.2 Kb) TX bytes:0 (0.0 b) > Interrupt:24 > > Its ifcfg-eth3 looks like: > # Broadcom Corporation|NetXtreme BCM5701 Gigabit Ethernet > DEVICE=eth3 > ONBOOT=yes > BOOTPROTO=static > IPADDR=10.156.30.176 > NETMASK=255.255.255.0 > HWADDR=00:0A:5E:7A:E7:33 > > But when I assign my laptop the address 10.156.30.213 and try to ping > 10.156.30.176 > I can't successfully do it through a crossover cable and further get > these messages > in /var/log/messages. What's wrong here? Got to be a config issue (I > think): > > Oct 2 12:13:41 host1 kernel: martian source 10.156.30.255 from > 10.156.30.213, on dev eth3 > Oct 2 12:13:41 host1 kernel: ll header: ff:ff:ff:ff:ff:ff: > 00:15:c5:47:d2:72:08:00 > Oct 2 12:14:50 host1 kernel: martian source 10.156.30.176 from > 10.156.30.213, on dev eth3 > Oct 2 12:14:50 host1 kernel: ll header: ff:ff:ff:ff:ff:ff: > 00:15:c5:47:d2:72:08:06 > Oct 2 12:14:55 host1 kernel: martian source 10.156.30.176 from > 10.156.30.213, on dev eth3 > Oct 2 12:14:55 host1 kernel: ll header: ff:ff:ff:ff:ff:ff: > 00:15:c5:47:d2:72:08:06 > Oct 2 12:15:00 host1 kernel: martian source 10.156.30.176 from > 10.156.30.213, on dev eth3 > Oct 2 12:15:00 host1 kernel: ll header: ff:ff:ff:ff:ff:ff: > 00:15:c5:47:d2:72:08:06 > Oct 2 12:15:06 host1 kernel: martian source 10.156.30.176 from > 10.156.30.213, on dev eth3 > Oct 2 12:15:06 host1 kernel: ll header: ff:ff:ff:ff:ff:ff: > 00:15:c5:47:d2:72:08:06 > Oct 2 12:15:47 host1 kernel: martian source 10.156.30.176 from > 10.156.30.213, on dev eth3 > Oct 2 12:15:47 host1 kernel: ll header: ff:ff:ff:ff:ff:ff: > 00:15:c5:47:d2:72:08:06 > Oct 2 12:15:56 host1 kernel: martian source 10.156.30.176 from > 10.156.30.213, on dev eth3 > Oct 2 12:15:56 host1 kernel: ll header: ff:ff:ff:ff:ff:ff: > 00:15:c5:47:d2:72:08:06 > > Netmask on my laptop is 255.255.255.0 > IP is 10.156.30.213 > No gateway specified. > > Routing table for linux host: > > [root(a)host1 user]# route > Kernel IP routing table > Destination Gateway Genmask Flags Metric Ref > Use Iface > 1.1.1.0 * 255.255.255.0 U 0 0 > 0 eth2 > 10.156.30.0 * 255.255.255.0 U 0 0 > 0 eth0 > 10.156.30.0 * 255.255.255.0 U 0 0 > 0 eth3 > default 10.156.30.1 0.0.0.0 UG 0 0 > 0 eth0 > > Please advise. > THANK YOU.
From: David Schwartz on 4 Oct 2009 22:10 On Oct 4, 2:46 am, Pascal Hambourg <boite-a-s...(a)plouf.fr.eu.org> wrote: > Short answer : no, you can't have the same IP subnet on separate > ethernet segments. This is the basic of IP addressing and routing. Well, you can, but you have to bridge them. It won't just magically work. (And you wouldn't want it to bridge automatically!) DS
From: Pascal Hambourg on 5 Oct 2009 04:41
David Schwartz a �crit : > On Oct 4, 2:46 am, Pascal Hambourg <boite-a-s...(a)plouf.fr.eu.org> > wrote: > >> Short answer : no, you can't have the same IP subnet on separate >> ethernet segments. This is the basic of IP addressing and routing. > > Well, you can, but you have to bridge them. Then they become parts of the same segment, and the assertion remains true. (Maybe "segment" is not the most appropriate term, "link layer" or "broadcast domain" may be more accurate) |