Re: dom0 broadcasts

["Sarton O'Brien" <bsd-xen%roguewrt.org@localhost>]

Manuel Bouyer wrote:
> On Thu, Feb 07, 2008 at 02:41:15PM +1100, Sarton O'Brien wrote:
> > Keeping it as simple as possible ...
> >
> > Broadcast ping from a domu:
> > symbiote# ping 192.168.x.255
> > PING 192.168.x.255 (192.168.x.255): 56 data bytes
> > 64 bytes from 192.168.x.9: icmp_seq=0 ttl=255 time=0.042 ms
> > 64 bytes from 192.168.x.8: icmp_seq=0 DUP! ttl=255 time=0.642 ms
> > 64 bytes from 192.168.x.7: icmp_seq=0 DUP! ttl=255 time=0.838 ms
> > 64 bytes from 192.168.x.6: icmp_seq=0 DUP! ttl=255 time=1.038 ms
> >
> > Broadcast ping from dom0:
> > gogeta# ping 192.168.x.255
> > PING 192.168.x.255 (192.168.x.255): 56 data bytes
> > 64 bytes from 192.168.x.10: icmp_seq=0 ttl=255 time=0.076 ms
> > 64 bytes from 192.168.x.8: icmp_seq=0 DUP! ttl=255 time=0.924 ms
> > 64 bytes from 192.168.x.9: icmp_seq=0 DUP! ttl=255 time=1.002 ms
> > 64 bytes from 192.168.x.7: icmp_seq=0 DUP! ttl=255 time=1.085 ms
> > 64 bytes from 192.168.x.6: icmp_seq=0 DUP! ttl=255 time=1.168 ms
> >
> > With x.10 being the IP address of dom0.
> >
> > Why doesn't dom0 respond to a broadcast from a domu?
> >
> > TIA for _any_ information :)
>
> I suspect a bridge issue. Do you have ipfiler enabled in dom0 ?
> What does a tcpdump on dom0 (on various involved interfaces) show ?

No ipf on dom0. Looking at tcpdump, the request is seen on all 
interfaces (bge0 and the various vifs) but bge0 is the only one not to 
respond.

Other than the fact there is no reply, everything looks normal.

From my understanding, the bridge should forward all broadcast packets, 
which is appears to, with all interfaces responding except bge0 ... 
could it be a configuration issue with bge0? All vifs are configured 
identically:

ifconfig -v bge0
bge0: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1500
capabilities=3f80<TSO4,IP4CSUM_Rx,IP4CSUM_Tx,TCP4CSUM_Rx,TCP4CSUM_Tx,UDP4CSUM_Rx,UDP4CSUM_Tx>
        enabled=0
        address: 00:13:72:18:02:ad
        media: Ethernet autoselect (100baseTX 
full-duplex,flowcontrol,rxpause,txpause)
        status: active
        input: 4152132 packets, 1679501463 bytes, 9762 multicasts
        output: 5096215 packets, 4062142379 bytes, 102 multicasts
        inet 192.168.210.10 netmask 0xffffff00 broadcast 192.168.210.255
        inet6 fe80::213:72ff:fe18:2ad%bge0 prefixlen 64 scopeid 0x1

ifconfig -v xvif6.0
xvif6.0: 
flags=8963<UP,BROADCAST,NOTRAILERS,RUNNING,PROMISC,SIMPLEX,MULTICAST> 
mtu 1500
        capabilities=2800<TCP4CSUM_Tx,UDP4CSUM_Tx>
        enabled=0
        address: 00:16:3e:62:0b:e3
        input: 6336510 packets, 3388795831 bytes, 3181 multicasts
        output: 7128788 packets, 6396590710 bytes, 654 multicasts
        inet6 fe80::216:3eff:fe62:be3%xvif6.0 prefixlen 64 scopeid 0x9

brconfig -a
bridge0: flags=41<UP,RUNNING>
        Configuration:
                priority 32768 hellotime 2 fwddelay 15 maxage 20
                ipfilter disabled flags 0x0
        Interfaces:
                xvif11.0 flags=3<LEARNING,DISCOVER>
                        port 10 priority 128
                xvif6.0 flags=3<LEARNING,DISCOVER>
                        port 9 priority 128
                xvif5.0 flags=3<LEARNING,DISCOVER>
                        port 8 priority 128
                xvif3.0 flags=3<LEARNING,DISCOVER>
                        port 6 priority 128
                bge0 flags=3<LEARNING,DISCOVER>
                        port 1 priority 128
        Address cache (max cache: 100, timeout: 1200):
                00:16:3e:61:0b:e3 xvif6.0 1197 flags=0<>
                00:16:3e:03:99:25 xvif5.0 1184 flags=0<>
                00:17:ab:f0:61:fe bge0 909 flags=0<>
                00:16:3e:3b:07:01 xvif11.0 884 flags=0<>
                00:0f:66:c5:2c:58 bge0 594 flags=0<>
                00:16:3e:6d:6d:e0 xvif3.0 584 flags=0<>


Sarton