using 2nd network interface - won't try to TX anything

I'm trying to make use of a 2nd ethernet interface. The basic steps seem
to work OK. But nothing gets transmitted out the 2nd interface. Yet it
does see packets coming back the other way on that interface.

Here's what ifconfig shows:

=============================================================================
-bash-2.05b# ifconfig
ixp1 Link encap:Ethernet HWaddr 00:02:B3:02:02:02
inet addr:172.30.1.3 Bcast:172.30.1.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:21049 errors:0 dropped:0 overruns:0 frame:0
TX packets:16493 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:256
RX bytes:17841196 (17.0 Mb) TX bytes:2523518 (2.4 Mb)

ixp2 Link encap:Ethernet HWaddr 00:02:B3:03:03:03
inet addr:172.30.2.3 Bcast:172.30.2.255 Mask:255.255.255.0
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:222 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:256
RX bytes:13320 (13.0 Kb) TX bytes:0 (0.0 b)

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:8 errors:0 dropped:0 overruns:0 frame:0
TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:560 (560.0 b) TX bytes:560 (560.0 b)

-bash-2.05b#
=============================================================================

One thing I notice here that might be an issue is that the status RUNNING
is not included in ixp2. Could that be related to the problem? How would
I fix this if so?

TX bytes is 0 for ixp2 despite attempts to ping the other host on that LAN
segment. I'd think that if it were bad hardware, it would at least show
what it it tried to transmit. But there is 0 there as if it never tried
to send anything over ixp2 at all.

Here's what route shows:

=============================================================================
-bash-2.05b# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
172.30.1.0 * 255.255.255.0 U 0 0 0 ixp1
172.30.2.0 * 255.255.255.0 U 0 0 0 ixp2
169.254.0.0 * 255.255.0.0 U 0 0 0 lo
-bash-2.05b#
=============================================================================

The topology is that ixp1 is connected via a switch to eth1 on a PC, and
ixp2 is connected via a different switch to eth2 on the same PC. There are
not other hosts connected on these segments. There is no default gateway
as this test machine is not to be able to reach the internet.

Notice for ixp2 in the ifconfig output, there are some RX bytes tallied.
This goes up when I ping that IP address from the PC. During such ping
attempts, the PC attempts to get the MAC address, but is unsuccessful.
The tcpdump output from the PC looks like lots of:

=============================================================================
....
17:39:11.723759 arp who-has 172.30.2.3 tell 172.30.2.1
17:39:13.723775 arp who-has 172.30.2.3 tell 172.30.2.1
17:39:14.723782 arp who-has 172.30.2.3 tell 172.30.2.1
17:39:15.723790 arp who-has 172.30.2.3 tell 172.30.2.1
....
=============================================================================

So I suspect the RX bytes tally is for the ARP request broadcasts received.
The ARP table on the PC shows the ping target as incomplete. But the ARP
table on the machine under test does show the corresponding PC MAC address.
So it apparently sent an ARP request and got and answer, but did not count
it, or sent it via the other interface.

=============================================================================
-bash-2.05b# arp
Address HWtype HWaddress Flags Mask Iface
172.30.2.1 ether 00:50:FC:4A:C2:1C C ixp2
172.30.1.1 ether 00:07:40:8E:56:A4 C ixp1
-bash-2.05b# ping 172.30.2.1
PING 172.30.2.1 (172.30.2.1) 56(84) bytes of data.

--- 172.30.2.1 ping statistics ---
96 packets transmitted, 0 received, 100% packet loss, time 95007ms

-bash-2.05b# arp
Address HWtype HWaddress Flags Mask Iface
172.30.2.1 ether 00:50:FC:4A:C2:1C C ixp2
172.30.1.1 ether 00:07:40:8E:56:A4 C ixp1
-bash-2.05b#
=============================================================================

The PC doing the testing has the following:

=============================================================================
root@tanith:/root 82# ifconfig
eth0 Link encap:Ethernet HWaddr 00:50:FC:B3:5F:26
inet addr:172.30.0.1 Bcast:172.30.0.255 Mask:255.255.255.0
inet6 addr: fe80::250:fcff:feb3:5f26/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:3623 errors:0 dropped:0 overruns:0 frame:0
TX packets:3603 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:224207 (218.9 KiB) TX bytes:1998944 (1.9 MiB)
Interrupt:201 Base address:0x6000

eth1 Link encap:Ethernet HWaddr 00:07:40:8E:56:A4
inet addr:172.30.1.1 Bcast:172.30.1.255 Mask:255.255.255.0
inet6 addr: fe80::207:40ff:fe8e:56a4/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:152725 errors:0 dropped:0 overruns:0 frame:0
TX packets:193340 errors:0 dropped:0 overruns:0 carrier:0
collisions:32254 txqueuelen:1000
RX bytes:19980287 (19.0 MiB) TX bytes:176632964 (168.4 MiB)
Interrupt:209 Base address:0x8000

eth2 Link encap:Ethernet HWaddr 00:50:FC:4A:C2:1C
inet addr:172.30.2.1 Bcast:172.30.2.255 Mask:255.255.255.0
inet6 addr: fe80::250:fcff:fe4a:c21c/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:28685 errors:0 dropped:0 overruns:0 frame:0
TX packets:29568 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:1728314 (1.6 MiB) TX bytes:16021972 (15.2 MiB)
Interrupt:217 Base address:0x4000

eth3 Link encap:Ethernet HWaddr 00:0D:61:4D:C9:3A
inet addr:192.168.2.27 Bcast:192.168.2.255 Mask:255.255.255.0
inet6 addr: fe80::20d:61ff:fe4d:c93a/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:8068633 errors:0 dropped:0 overruns:0 frame:0
TX packets:5464124 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:3225398207 (3.0 GiB) TX bytes:371598322 (354.3 MiB)
Interrupt:201 Base address:0xd000

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:224639 errors:0 dropped:0 overruns:0 frame:0
TX packets:224639 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:1748770581 (1.6 GiB) TX bytes:1748770581 (1.6 GiB)

root@tanith:/root 83# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
172.30.1.0 * 255.255.255.0 U 0 0 0 eth1
192.168.2.0 * 255.255.255.0 U 0 0 0 eth3
172.30.0.0 * 255.255.255.0 U 0 0 0 eth0
172.30.2.0 * 255.255.255.0 U 0 0 0 eth2
169.254.0.0 * 255.255.0.0 U 0 0 0 eth3
default 192.168.2.2 0.0.0.0 UG 0 0 0 eth3
root@tanith:/root 84# arp
Address HWtype HWaddress Flags Mask Iface
172.30.2.3 (incomplete) eth2
192.168.2.241 ether 00:0E:2E:53:3E:CA C eth3
192.168.2.23 ether 00:12:3F:2A:D4:86 C eth3
172.30.1.3 ether 00:02:B3:02:02:02 C eth1
192.168.2.2 ether 00:06:B1:34:AD:B0 C eth3
192.168.2.12 ether 00:14:22:7B:5D:38 C eth3
192.168.2.231 ether 00:01:02:9B:3C:A9 C eth3
=============================================================================

Interface eth3 on the PC is the connection to the office LAN using a different
private IP space.

Interface eth0 is currently not connected on the PC.

--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
| first name lower case at ipal.net / spamtrap-2007-05-10-1632@xxxxxxxx |
|------------------------------------/-------------------------------------|
.

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