ot: who to report a bug in if_tap to?

Aryeh Friedman aryeh.friedman at gmail.com
Tue Aug 13 17:43:07 UTC 2013


It is connected to the physical nic via a switch (no intermediate
routers).   DHCP doesn't even attempt because there is no carrier on
tap0:

em0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
	options=4219b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM,TSO4,WOL_MAGIC,VLAN_HWTSO>
	ether 30:85:a9:ec:24:95
	inet 10.0.10.10 netmask 0xffffff00 broadcast 10.0.10.255
	inet6 fe80::3285:a9ff:feec:2495%em0 prefixlen 64 scopeid 0x1
	nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
	media: Ethernet autoselect (100baseTX <full-duplex>)
	status: active
re0: flags=8802<BROADCAST,SIMPLEX,MULTICAST> metric 0 mtu 1500
	options=8209b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM,WOL_MAGIC,LINKSTATE>
	ether 90:f6:52:00:40:e6
	nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
	media: Ethernet autoselect (100baseTX <half-duplex>)
	status: no carrier
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> metric 0 mtu 16384
	options=600003<RXCSUM,TXCSUM,RXCSUM_IPV6,TXCSUM_IPV6>
	inet 127.0.0.1 netmask 0xff000000
	inet6 ::1 prefixlen 128
	inet6 fe80::1%lo0 prefixlen 64 scopeid 0x3
	nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
tap0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
	options=80000<LINKSTATE>
	ether 00:bd:0c:6e:02:00
	inet6 fe80::2bd:cff:fe6e:200%tap0 prefixlen 64 scopeid 0x4
	nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
	media: Ethernet autoselect
	status: no carrier
root at petitecloud:/home/aryeh # if
if       ifconfig ifmcstat
root at petitecloud:/home/aryeh # ifconfig bridge0 create
root at petitecloud:/home/aryeh # ifconfig bridge0 addm em0 addm tap0
root at petitecloud:/home/aryeh # ifconfig tap0 10.0.10.3
root at petitecloud:/home/aryeh # ifconfig -a
em0: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> metric
0 mtu 1500
	options=42098<VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM,WOL_MAGIC,VLAN_HWTSO>
	ether 30:85:a9:ec:24:95
	inet 10.0.10.10 netmask 0xffffff00 broadcast 10.0.10.255
	inet6 fe80::3285:a9ff:feec:2495%em0 prefixlen 64 scopeid 0x1
	nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
	media: Ethernet autoselect (100baseTX <full-duplex>)
	status: active
tap0: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST>
metric 0 mtu 1500
	options=80000<LINKSTATE>
	ether 00:bd:0c:6e:02:00
	inet6 fe80::2bd:cff:fe6e:200%tap0 prefixlen 64 scopeid 0x4
	inet 10.0.10.3 netmask 0xff000000 broadcast 10.255.255.255
	nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
	media: Ethernet autoselect
	status: no carrier
bridge0: flags=8802<BROADCAST,SIMPLEX,MULTICAST> metric 0 mtu 1500
	ether f6:3c:f0:0f:b9:48
	nd6 options=1<PERFORMNUD>
	id 00:00:00:00:00:00 priority 32768 hellotime 2 fwddelay 15
	maxage 20 holdcnt 6 proto rstp maxaddr 2000 timeout 1200
	root id 00:00:00:00:00:00 priority 0 ifcost 0 port 0
	member: tap0 flags=143<LEARNING,DISCOVER,AUTOEDGE,AUTOPTP>
	        ifmaxaddr 0 port 4 priority 128 path cost 2000000
	member: em0 flags=143<LEARNING,DISCOVER,AUTOEDGE,AUTOPTP>
	        ifmaxaddr 0 port 1 priority 128 path cost 200000
root at vcloud:/home/aryeh # dhclient tap0
tap0: no link .............. giving up

On Tue, Aug 13, 2013 at 1:19 PM, Peter Grehan <grehan at freebsd.org> wrote:
> Hi Aryeh,
>
>
>> It appears that a bridged if_tap does not understand DHCP on the
>> physical NIC... who do I report this to?
>
>
>  First, what's your configuration ? Is the DHCP server connected via the
> physical NIC ? What does a tcpdump show ?
>
> later,
>
> Peter.
>


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