Hi, I am trying to get multiple UML instances talk to each other using a bridge. For this I am using eth1 interface on the host. It is not the public interface since I do not require internet access from the UMLs. I just want them to talk to each other ( I could do that with uml_switch, but I would like to do this with bridging for various reasons).
I followed the steps at http://user-mode-linux.sourceforge.net/networking.html. I can ping the bridge IP from the UMLs but the ping from UML 1 to UML 2 fails. UML 1 : 192.168.0.3 UML 2 : 192.168.0.4 Bridge (uml-bridge) : 192.168.0.100 I also tried this without using any host interface added to the bridge and just adding the tap interfaces, since I do not need any external connectivity. That didnt work either. On doing a ping/traceroute from UML1 to UML2 , using tcpdump I can see that UML2 gets the arp packets and it replies correctly : 15:55:59.039186 arp who-has 192.168.0.4 tell 192.168.0.3 15:55:59.039313 arp reply 192.168.0.4 is-at fe:fd:c0:a8:00:04 But it does not get the following UDP packets from traceroute sent by UML1. So it looks like the bridge is letting arp packets through but not the IP packets. I have tried setting the host as a gateway ( putting 1 in ip_forward..) but that didnt help ( I guess it shouldnt matter as the bridging happens at layer 2 anyways). Any help, pointers or doc/sites references will be a great help. thanks Shavian. ps: The routing tables, ifconfig outputs etc on UML1, UML2 and the host are pasted below. UML1: ------ eth0 Link encap:Ethernet HWaddr FE:FD:C0:A8:00:04 inet addr:192.168.0.4 Bcast:192.168.0.255 Mask:255.255.255.0 inet6 addr: fe80::fcfd:c0ff:fea8:4/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:177918 errors:0 dropped:0 overruns:0 frame:0 TX packets:22 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:10542966 (10.0 Mb) TX bytes:1804 (1.7 Kb) Interrupt:5 Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 192.168.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo 0.0.0.0 192.168.0.100 0.0.0.0 UG 0 0 0 eth0 UML2: ------ eth0 Link encap:Ethernet HWaddr FE:FD:C0:A8:00:03 inet addr:192.168.0.3 Bcast:192.168.0.255 Mask:255.255.255.0 inet6 addr: fe80::fcfd:c0ff:fea8:3/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:180645 errors:0 dropped:0 overruns:0 frame:0 TX packets:13 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:10704528 (10.2 Mb) TX bytes:978 (978.0 b) Interrupt:5 Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 192.168.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo 0.0.0.0 192.168.0.100 0.0.0.0 UG 0 0 0 eth0 um4_lnx21:~ # Host ---- ifconfig output (the relevant interfaces): eth1 Link encap:Ethernet HWaddr 00:06:5B:ED:64:83 inet6 addr: fe80::206:5bff:feed:6483/64 Scope:Link UP BROADCAST RUNNING PROMISC MULTICAST MTU:1500 Metric:1 RX packets:151743 errors:0 dropped:0 overruns:0 frame:0 TX packets:21 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:11724301 (11.1 Mb) TX bytes:1654 (1.6 Kb) Base address:0xdcc0 Memory:feb20000-feb40000 uml-bridg Link encap:Ethernet HWaddr 00:06:5B:ED:64:83 inet addr:192.168.0.100 Bcast:192.168.0.255 Mask:255.255.255.0 inet6 addr: fe80::200:ff:fe00:0/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:148504 errors:0 dropped:0 overruns:0 frame:0 TX packets:9 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:8800989 (8.3 Mb) TX bytes:686 (686.0 b) uml-conn0 Link encap:Ethernet HWaddr 00:FF:17:CB:6D:5C inet6 addr: fe80::2ff:17ff:fecb:6d5c/64 Scope:Link UP BROADCAST RUNNING PROMISC MULTICAST MTU:1500 Metric:1 RX packets:13 errors:0 dropped:0 overruns:0 frame:0 TX packets:139501 errors:0 dropped:6768 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:978 (978.0 b) TX bytes:10219330 (9.7 Mb) uml-conn1 Link encap:Ethernet HWaddr 00:FF:ED:97:29:8F inet6 addr: fe80::2ff:edff:fe97:298f/64 Scope:Link UP BROADCAST RUNNING PROMISC MULTICAST MTU:1500 Metric:1 RX packets:22 errors:0 dropped:0 overruns:0 frame:0 TX packets:138539 errors:0 dropped:7633 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:1804 (1.7 Kb) TX bytes:10148894 (9.6 Mb) Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 192.168.0.0 0.0.0.0 255.255.255.0 U 0 0 0 uml-bridge 10.182.0.0 0.0.0.0 255.255.240.0 U 0 0 0 eth0 127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo 0.0.0.0 10.182.1.1 0.0.0.0 UG 0 0 0 eth0 ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_ide95&alloc_id396&op=click _______________________________________________ User-mode-linux-user mailing list User-mode-linux-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-user
