Why all devices (RB1100AH, RB1100AHx2, RB751G, RB2011) with AR8327 doesn't support port trunking?

Just simple case, no hybrid ports:
1. one port as tagged
2. one or more ports as untagged

Why there is limitation to one master port per switch group?

I'm asking because this is definitely not hardware limitation.

--

I did some testing. Here are results:

1. I have router (RB751G-2HuND) on which I installed latest attitude adjustment (12.09rc1) (https://forum.openwrt.org/viewtopic.php?id=39171).

2. I have 3 ports in use:
Port 1. WAN connection, uses DHCP
Port 2. Nucleus, Intel Atom, Debian/Squeeze, connected using 100Mbps/FD ethernet.
Port 3. Raspberry PI, OpenWrt 12.09rc1, connected using 100Mbps/FD ethernet.

3. I created 5 VLANs. You can see switch chip configuration on attached screenshot.
VLAN 1. LAN: untagged Port 2 goes as tagged to CPU. In system visible as eth0.1. eth0.1 is bridged with wlan.
VLAN 2. WAN: untagged Port 1 goes as tagged to CPU. In system visible as eth0.2. On eth0.2 dhcp-client is being run.
VLAN 4. untagged Port 3 goes as tagged to Port 2 with VLANID 4.
VLAN 5. untagged Port 4 goes as tagged to Port 2 with VLANID 5.
VLAN 6. untagged Port 5 goes as tagged to Port 2 with VLANID 6.

4. On nucleus I have all VLANIDs configured (eth0.1, eth0.4, eth0.5, eth0.6) and bridged together. So devices connected to port 3, 4 or 5 should always be reachable from router's CPU port.

5. Because I only have one other device (Raspberry PI) i did plug it to port 3, then to port 4 and then to port 5. Each time traffic coming from Raspberry PI to nucleus was coming from different VLANID (as expected).

To support my results here are tcpdump's:

Raspberry PI connected to port 3

root@nucleus:~# tcpdump -i eth0 -e icmp -vn
tcpdump: WARNING: eth0: no IPv4 address assigned
tcpdump: listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes
15:09:08.537500 ac:72:89:24:a1:03 > b8:27:eb:4e:a6:d8, ethertype 802.1Q (0x8100), length 78: vlan 1, p 0, ethertype IPv4, (tos 0x0, ttl 128, id 914, offset 0, flags [none], proto ICMP (1), length 60)
192.168.88.12 > 192.168.88.38: ICMP echo request, id 1, seq 4750, length 40
15:09:08.537532 ac:72:89:24:a1:03 > b8:27:eb:4e:a6:d8, ethertype 802.1Q (0x8100), length 78: vlan 4, p 0, ethertype IPv4, (tos 0x0, ttl 128, id 914, offset 0, flags [none], proto ICMP (1), length 60)
192.168.88.12 > 192.168.88.38: ICMP echo request, id 1, seq 4750, length 40
15:09:08.538086 b8:27:eb:4e:a6:d8 > ac:72:89:24:a1:03, ethertype 802.1Q (0x8100), length 78: vlan 4, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 49827, offset 0, flags [none], proto ICMP (1), length 60)
192.168.88.38 > 192.168.88.12: ICMP echo reply, id 1, seq 4750, length 40
15:09:08.538104 b8:27:eb:4e:a6:d8 > ac:72:89:24:a1:03, ethertype 802.1Q (0x8100), length 78: vlan 1, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 49827, offset 0, flags [none], proto ICMP (1), length 60)
192.168.88.38 > 192.168.88.12: ICMP echo reply, id 1, seq 4750, length 40

Raspberry PI connected to port 4

root@nucleus:~# tcpdump -i eth0 -e icmp -vn
tcpdump: WARNING: eth0: no IPv4 address assigned
tcpdump: listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes
15:08:44.802239 ac:72:89:24:a1:03 > b8:27:eb:4e:a6:d8, ethertype 802.1Q (0x8100), length 78: vlan 1, p 0, ethertype IPv4, (tos 0x0, ttl 128, id 864, offset 0, flags [none], proto ICMP (1), length 60)
192.168.88.12 > 192.168.88.38: ICMP echo request, id 1, seq 4730, length 40
15:08:44.802259 ac:72:89:24:a1:03 > b8:27:eb:4e:a6:d8, ethertype 802.1Q (0x8100), length 78: vlan 5, p 0, ethertype IPv4, (tos 0x0, ttl 128, id 864, offset 0, flags [none], proto ICMP (1), length 60)
192.168.88.12 > 192.168.88.38: ICMP echo request, id 1, seq 4730, length 40
15:08:44.802702 b8:27:eb:4e:a6:d8 > ac:72:89:24:a1:03, ethertype 802.1Q (0x8100), length 78: vlan 5, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 49829, offset 0, flags [none], proto ICMP (1), length 60)
192.168.88.38 > 192.168.88.12: ICMP echo reply, id 1, seq 4730, length 40
15:08:44.802720 b8:27:eb:4e:a6:d8 > ac:72:89:24:a1:03, ethertype 802.1Q (0x8100), length 78: vlan 1, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 49829, offset 0, flags [none], proto ICMP (1), length 60)

Raspberry PI connected to port 5

root@nucleus:~# tcpdump -i eth0 -e icmp -vn
tcpdump: WARNING: eth0: no IPv4 address assigned
tcpdump: listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes
15:08:12.138500 ac:72:89:24:a1:03 > b8:27:eb:4e:a6:d8, ethertype 802.1Q (0x8100), length 78: vlan 1, p 0, ethertype IPv4, (tos 0x0, ttl 128, id 796, offset 0, flags [none], proto ICMP (1), length 60)
192.168.88.12 > 192.168.88.38: ICMP echo request, id 1, seq 4712, length 40
15:08:12.138529 ac:72:89:24:a1:03 > b8:27:eb:4e:a6:d8, ethertype 802.1Q (0x8100), length 78: vlan 6, p 0, ethertype IPv4, (tos 0x0, ttl 128, id 796, offset 0, flags [none], proto ICMP (1), length 60)
192.168.88.12 > 192.168.88.38: ICMP echo request, id 1, seq 4712, length 40
15:08:12.139124 b8:27:eb:4e:a6:d8 > ac:72:89:24:a1:03, ethertype 802.1Q (0x8100), length 78: vlan 6, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 49836, offset 0, flags [none], proto ICMP (1), length 60)
192.168.88.38 > 192.168.88.12: ICMP echo reply, id 1, seq 4712, length 40
15:08:12.139143 b8:27:eb:4e:a6:d8 > ac:72:89:24:a1:03, ethertype 802.1Q (0x8100), length 78: vlan 1, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 49836, offset 0, flags [none], proto ICMP (1), length 60)
192.168.88.38 > 192.168.88.12: ICMP echo reply, id 1, seq 4712, length 40

Legend:
1. 192.168.88.12 - this is the IP address of my laptop connected to router over wifi. From switch chip perspective is the CPU port.
2. vlan 1 - this is traffic coming from router (wifi too) as described earlier.
3. 192.168.88.38 - this is the IP address of Raspberry PI.
4. vlan 4/5/6 - this is traffic outgoing to Raspberry PI.

Conclusion:
1. Port trunking works as expected on AR8327. Hybrid configuration is not working.
2. Problem with trunking on RouterOS is definitely not hardware related, but buggy implementation of switch chip.
3. Switch chip allows to have multi-master port configuration.
4. If you need port trunking RouterOS is NOGO!
5. OpenWrt supports it out of box: wire speed port trunking (no hybrid configuration) and multi-master port configuration.

My assumptions:
1. RouterOS switch chip configuration is over complicated in some simple use-case as port trunking (Just read: http://wiki.mikrotik.com/wiki/Manual:Sw ... p_Features Example - 802.1Q Trunking with Atheros 8316). In order to use port trunking you have to use switch chip rules? hahaha
2. RouterOS switch chip implementation is messy and buggy. I somehow managed to partially configure hybrid port configuration on RouterOS.
2. RouterOS switch chip configuration maps individual ports to VLANIDs. In system these VLANIDs are separate switch chip ports. Master port configuration groups these ports together to one VLANID.
3. What we really miss is the PVID and trunking port option in Switch Chip port's view. We definitely don't need rules to setup port trunking.

Devices configuration:

root@router:/etc/config# cat network

config interface 'loopback'
option ifname 'lo'
option proto 'static'
option ipaddr '127.0.0.1'
option netmask '255.0.0.0'

config interface 'lan'
option ifname 'eth0.1'
option type 'bridge'
option proto 'static'
option netmask '255.255.255.0'
option ipaddr '192.168.88.1'

config interface 'wan'
option ifname 'eth0.2'
option proto 'dhcp'

config switch
option name 'switch0'
option reset '1'
option enable_vlan '1'

config switch_vlan
option device 'switch0'
option vlan '1'
option vid '1'
option ports '0t 2t'

config switch_vlan
option device 'switch0'
option vlan '2'
option ports '0t 1'
option vid '2'

config switch_vlan
option device 'switch0'
option vlan '3'
option vid '4'
option ports '2t 3'

config switch_vlan
option device 'switch0'
option vlan '4'
option vid '5'
option ports '2t 4'

config switch_vlan
option device 'switch0'
option vlan '5'
option vid '6'
option ports '2t 5'

root@nucleus:~# ifconfig
eth0 Link encap:Ethernet HWaddr 00:21:85:e0:76:b4
eth0.1 Link encap:Ethernet HWaddr 00:21:85:e0:76:b4
eth0.4 Link encap:Ethernet HWaddr 00:21:85:e0:76:b4
eth0.5 Link encap:Ethernet HWaddr 00:21:85:e0:76:b4
eth0.6 Link encap:Ethernet HWaddr 00:21:85:e0:76:b4
vmbr0 Link encap:Ethernet HWaddr c2:3a:c8:ea:f5:dd

root@nucleus:~# brctl show
bridge name bridge id STP enabled interfaces
vmbr0 8000.c23ac8eaf5dd no eth0.1
eth0.4
eth0.5
eth0.6

root@rpi:~# ifconfig
eth0 Link encap:Ethernet HWaddr B8:27:EB:4E:A6:D8
inet addr:192.168.88.38 Bcast:192.168.88.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:5413 errors:0 dropped:0 overruns:0 frame:0
TX packets:3426 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:420831 (410.9 KiB) TX bytes:365166 (356.6 KiB)

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:7792 errors:0 dropped:0 overruns:0 frame:0
TX packets:7792 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:530388 (517.9 KiB) TX bytes:530388 (517.9 KiB)

Thanks, I needed this informations. I would like to use wire speed with trunking and I now see it is not possible.

Any news on this?

Thanks,
Mario

Nope. No response from support. It is not possible on RouterOS and fairly simple on OpenWrt. So... :)

Any progress?

Any progress?

Trunking with AR8327 switch chip is working since RouterOS v6.0:
http://wiki.mikrotik.com/wiki/Manual:Sw ... p_Features

Any progress?

I will have a presentation on the next MUM (in 2 days), showing how easy it is .

Any progress?

I will have a presentation on the next MUM (in 2 days), showing how easy it is .

Will you make your presentation available online (after MUM)?

Found this one: http://mum.mikrotik.com/presentations/I ... nowski.pdf

Found this one: http://mum.mikrotik.com/presentations/I ... nowski.pdf

This presentation is not accurate (or only based on what wiki says), because in reality with the switch chip you can use hybrid ports :) At least it works on RB1100AHx2 and RB951G-2HnD. What I've also discovered that VLAN header setting doesn't make any difference at all.