# After upgrade from 13.0-RELEASE to 13.1-RELEASE not able to add vxlan and tap interfaces to bridge simultaneously



## Andy1585 (Dec 22, 2022)

Hi FreeBSD community!
`# uname -a
FreeBSD <hostname> 13.1-RELEASE-p3 FreeBSD 13.1-RELEASE-p3 GENERIC amd64`

After upgrade from 13.0-RELEASE to 13.1-RELEASE can add just `vxlan` or just `tap` to `bridge`, but not both.

Interfaces:
`# ifconfig vxlan101
vxlan101: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1450
    options=80020<JUMBO_MTU,LINKSTATE>
    ether 58:9c:fc:10:2d:14
    groups: vxlan
    vxlan vni 101 local <IP>:<PORT> remote <IP>:<PORT>
    media: Ethernet autoselect (autoselect <full-duplex>)
    status: active
    nd6 options=9<PERFORMNUD,IFDISABLED>

# ifconfig tap101
tap101: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
    options=80000<LINKSTATE>
    ether 58:9c:fc:10:0f:3d
    groups: tap
    media: Ethernet autoselect
    status: active
    nd6 options=9<PERFORMNUD,IFDISABLED>
    Opened by PID 6767

# ifconfig bridge101
bridge101: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
    ether 58:9c:fc:10:fd:24
    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 32768 ifcost 0 port 0
    groups: bridge
    nd6 options=9<PERFORMNUD,IFDISABLED>`

Now if add tap, then try to add vxlan:
`# ifconfig bridge101 addm tap101
# ifconfig bridge101 addm vxlan101`
error:
`ifconfig: BRDGADD vxlan101: Invalid argument`

or if add vxlan, then try to add tap:
`# ifconfig bridge101 addm vxlan101
# ifconfig bridge101 addm tap101`
error:
`ifconfig: BRDGADD tap101: Invalid argument`

Tried to equal mtu to 1500 on all interfaces but error the same.

Any ideas?


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## covacat (Dec 22, 2022)

create the bridge
set tap mtu 1470
add it to the bridge
add vxlan to the bridge
the first add will set bridge mtu to 1470


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## Andy1585 (Dec 22, 2022)

covacat said:


> create the bridge
> set tap mtu 1470
> add it to the bridge
> add vxlan to the bridge
> the first add will set bridge mtu to 1470


Thanks for reply, it works even after a reboot, but I would like to avoid possible problems with mtu (ICMP type 3 code 4 "Fragmentation required, DF bit set" may not work everywhere), hardware supports jumbo frames and overhead is not a problem. So I tried again to change vxlan mtu to 1500 and now vxlan seems to be added to bridge+tap without error... Now I added "mtu 1500" to vxlan initialization in rc.conf. It didn't work at first time because the rc.d scripts configure virtual interfaces in order they appear in "clonted_interfaces=..." and not in order they appear in "ifconfig_<interfacename>= ..." in rc.conf and vxlans were configured after bridges. I didn't know that... So I just reordered "cloned_interfaces=..." and moved bridges to the end of the line. Now everything works. Thank you.


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