can't ping over crossover cable (get martian source)
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From: The Derfer on 2 Oct 2009 17:00 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: Burkhard Ott on 2 Oct 2009 17:46 On Fri, 02 Oct 2009 14:00:24 -0700, The Derfer wrote: > 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 Your networks are on both interfaces (eth0 and eth3).
From: The Derfer on 2 Oct 2009 18:58 On Oct 2, 5:46 pm, Burkhard Ott <news2...(a)derith.de> wrote: > On Fri, 02 Oct 2009 14:00:24 -0700, The Derfer wrote: > >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 > > Your networks are on both interfaces (eth0 and eth3). What do I need to do? I don't understand your response.
From: Burkhard Ott on 2 Oct 2009 20:41 Am Fri, 02 Oct 2009 15:58:10 -0700 schrieb The Derfer: > On Oct 2, 5:46 pm, Burkhard Ott <news2...(a)derith.de> wrote: >> On Fri, 02 Oct 2009 14:00:24 -0700, The Derfer wrote: >> >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 >> >> Your networks are on both interfaces (eth0 and eth3). > > What do I need to do? I don't understand your response. Usually you should assign a network only to one interface, there are special cases to have the same network on 2 independet interfaces but in your case just assign the network to the interface which is connected to your x-link, the martian messages should disappear.
From: David Schwartz on 2 Oct 2009 21:55
On Oct 2, 3:58 pm, The Derfer <derf...(a)gmail.com> wrote: > On Oct 2, 5:46 pm, Burkhard Ott <news2...(a)derith.de> wrote: > > > On Fri, 02 Oct 2009 14:00:24 -0700, The Derfer wrote: > > >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 > > > Your networks are on both interfaces (eth0 and eth3). > > What do I need to do? I don't understand your response. Your routing setup is extremely weird. Your default route is: default 10.156.30.1 0.0.0.0 UG 0 0 0 eth0 But if 10.156.30.0/24 is routed to eth3, how can 10.156.30.1 be reachable through eth0 directly? You'd have to have some weird proxy ARP setup. It looks like you have two network interfaces that are configured as nonoverlapping networks, given IP addresses on overlapping networks, and routed as non-overlapping networks. If there's an ethernet network that corresponds to 10.156.30.0/24, it needs to be connected to either eth0 or eth3. Otherwise, you need a configuration that makes sense for two interfaces on the same IP network, such as bridging. DS |