> On Dec 7, 2021, at 5:39 AM, Marek Zarychta <zarych...@plan-b.pwste.edu.pl>
> wrote:
>
> W dniu 8.11.2021 o 08:13, Zhenlei Huang pisze:
>>> On Nov 7, 2021, at 3:51 PM, Rozhuk Ivan <rozhuk...@gmail.com> wrote:
>>>
>>> Hi!
>>>
>>>
>>> Why if_vlan allow to set same MTU size or bigger as on parrent nic?
>>>
>>>
>>> Setup:
>>> - workstation with MTU 9000 and IPv4 on h/w nic
>>> - server with MTU 9000 on h/w nic and IPv4 on vlan nic with MTU 9000 (set
>>> by defauil on iface creation)
>>>
>>> This setup have issue:
>>> - big packets from server->wks - OK
>>> - big packets from wks->server - FAIL.
>>>
>>> Server init sequence:
>>> 1. Create vlans
>>> 2. Set MTU lower than default on parent nic
>>>
>>> Result: vlan have bigger or same MTU as parrent nic, but parrent nic
>>> reports IFCAP_VLAN_MTU.
>>> Probably this is if_em driver issue or iflib.
>>>
>>>
>>>
>>> This is rc.conf, vlan77 - where I got MTU 9000 and fail to receive packets:
>>> =====================================================================================
>>> vlans_igb0="vlan77 vlan86 vlan87"
>>> create_args_vlan87="vlan 87"
>>> create_args_vlan86="vlan 86"
>>> create_args_vlan77="vlan 77"
>>> ifconfig_vlan87="inet 15.44.77.2 netmask 255.255.252.0 mtu 1500 down up"
>>> ifconfig_vlan87_alias0="link 00:aa:fa:dd:44:55"
>>> ifconfig_vlan86="DHCP mtu 1500"
>>> ifconfig_vlan86_alias0="link 00:ff:fa:dd:44:55"
>>> ifconfig_vlan77="inet 192.168.0.254 netmask 255.255.255.0"
>>> ifconfig_vlan77_alias0="link 00:0f:43:48:67:fe"
>>> ifconfig_vlan77_ipv6="inet6 2001:470:2345:555::1/64 prefixlen 64
>>> auto_linklocal"
>>> ifconfig_igb0="-lro -tso -vlanhwtso mtu 9000 down up"
>>> =====================================================================================
>>>
>>>
>>>
>> Can you please disable all vlan hardware offloading features and repeat the
>> test again?
>> ifconfig igb0 -vlanmtu -vlanhwtag -vlanhwfilter -vlanhwtso -vlanhwcsum
>
> Disabling the capabilities listed above doesn't solve the issue, but
> assigning mtu 8996 to VLAN children does.
> Reproduced on the most recent 13-STABLE (13-n248421-3b936a8c889) while
> testing the fix[1]
>
> To reproduce:
>
> ifconfig_igb0="mtu 9000 up"
> ifconfig_igb1="mtu 9000 up"
Try disabling all vlan hardware offloading features in rc.conf.
ifconfig_igb0="mtu 9000 -vlanmtu -vlanhwtag -vlanhwfilter -vlanhwtso
-vlanhwcsum up"
ifconfig_igb1="mtu 9000 -vlanmtu -vlanhwtag -vlanhwfilter -vlanhwtso
-vlanhwcsum up"
> ifconfig_lagg0="laggproto lacp laggport igb0 laggport igb1 -lacp_strict"
> vlans_lagg0="vlan0 vlan1 ..."
> ifconfig_vlan0="inet x.x.x.x/y"
>
> # iperf3 -R -c y.y.y.y
> Connecting to host y.y.y.y, port 5201
> Reverse mode, remote host y.y.y.y is sending
> [ 5] local x.x.x.x port 52750 connected to y.y.y.y port 5201
> [ ID] Interval Transfer Bitrate
> [ 5] 0.00-1.02 sec 0.00 Bytes 0.00 bits/sec
> [ 5] 1.02-2.02 sec 0.00 Bytes 0.00 bits/sec
> [ 5] 2.02-3.02 sec 0.00 Bytes 0.00 bits/sec
> [ 5] 3.02-3.55 sec 0.00 Bytes 0.00 bits/sec
>
> #ifconfig vlan0 mtu 8996
>
> # iperf3 -R -c y.y.y.y
> Connecting to host y.y.y.y, port 5201
> Reverse mode, remote host y.y.y.y is sending
> [ 5] local x.x.x.x port 49056 connected to y.y.y.y port 5201
> [ ID] Interval Transfer Bitrate
> [ 5] 0.00-1.00 sec 118 MBytes 989 Mbits/sec
> [ 5] 1.00-2.00 sec 118 MBytes 990 Mbits/sec
> [ 5] 2.00-3.00 sec 118 MBytes 990 Mbits/sec
> [ 5] 3.00-3.69 sec 81.8 MBytes 989 Mbits/sec
>
> I am setting MTU to 8996 since early 13-BETA? or maybe PRERELEASE. 12-STABLE
> at the beginning of 2021 was fine with the default settings and MTU 9000 set
> for igb(4) on the same hardware. It looks like regression. Should the PR be
> submitted in this case?
>
> [1] https://reviews.freebsd.org/D30002 (commit
> 9c6432dc4bb936f0842d766d8b3b19dfcde15da2)
>
> Regards,
> --
> Marek Zarychta
