I have an issue with an Ubuntu 12.04 LTS (updated) server.
For reasons too long to detail, it has got one eth0 interface assigned to 192.168.1.9 and one Wifi wlan0 interface assigned to 192.168.1.10. Both MUST work since boot time.
I also installed (I need of monitoring software) Lubuntu desktop-core and removed Network manager (rebooted) and using wpa_supplicant + /etc/network/interface hardcoded configuration and fixed IPs.
Everything works like a charm... hardware wise. From the Lubuntu desktop I can browse the internet from eth0. If I
ifdown eth0 and then unplug it, I can happily browse the internet through wlan0. So
wpa_supplicant looks like it's doing its job.
The problem is...
I need to be able to have both interfaces up at the same time and both must respond to pings, SSH connects from the other computers in the LAN, etc.. The wlan0 is the one that will need to be used when communicating with the gateway/router (at 192.168.1.1) to exit to the internet.
But if I have both interfaces up, eth0 keeps working, but wlan0 becomes unreachable (nor it will connect to anything any more, so the issue is bidirectional). Trying to ping from My Win 8 computer will say the same error that you see when there's no route to host, too bad it's still on the same segment of the LAN: my Win 8 is at 192.168.1.69 and server's wlan0 is at 192.168.1.10.
Do you have any idea about where I could start look after?
Here are some configuration files
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:18 errors:0 dropped:0 overruns:0 frame:0 TX packets:18 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:1613 (1.6 KB) TX bytes:1613 (1.6 KB) wlan0 Link encap:Ethernet HWaddr 00:c0:49:fc:db:3f inet addr:192.168.1.10 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::2c0:49ff:fefc:db3f/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:16376 errors:0 dropped:0 overruns:0 frame:0 TX packets:3337 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:4675792 (4.6 MB) TX bytes:543084 (543.0 KB)
When I enable the eth0 with
ifup, I get this stanza added:
eth0 Link encap:Ethernet HWaddr 00:0e:a6:aa:5b:be inet addr:192.168.1.9 Bcast:192.168.1.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:0 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:0 (0.0 B) TX bytes:0 (0.0 B)
Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 192.168.1.1 0.0.0.0 UG 100 0 0 wlan0 192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 wlan0 192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
If I disable eth0 of course the relevant line goes away. IPTables shows clean (fresh Ubuntu install), I'm using UFW but I have disabled it at the moment as well.
iptables -L -nv:
Chain INPUT (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination Chain FORWARD (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination Chain OUTPUT (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination
hostsfile I have both interfaces, set to different names.
resolv.confI've only got the DNS servers IP and domain clause.