Possible regression? Dual band SSID + 2 other SSIDS on the same bridge, connectivity problems

dijx · February 27, 2022, 8:34pm

Well, it may be a regression:

FS#714 - ARP/Broadcast does not reach other clients in the same WLAN

opened 04:20PM - 17 Apr 17 UTC

flyspray

*Jakeler:* I have the default bridge with ethernet and WLAN in it. When i try t…o send data from a client to another, both connected to the same WLAN SSID, it doesn't work (Destination unreachable). Wireshark shows that it sends endless ARP requests to Broadcast, but the other clients in that WLAN never get it (and therefore can't answer). The broadcast gets still delivery to every client connected through Ethernet. If i create a second WLAN SSID (even on the same adapter) and and add it to the bridge, it gets also all broadcast packets from the other WLAN... So if i put the 2 clients in different WLAN SSIDs or ethernet they get the broadcast from each other, but not when both are connected to the same. The isolate option is not set in the wireless config. Archer C5 v1 with latest LEDE snapshot (no difference to 17.01 stable or rc).

grep -c ap_isolate /var/run/hostapd-phy*.conf
/var/run/hostapd-phy0.conf:2
/var/run/hostapd-phy1.conf:2

I did not set isolation, but all wlans have that apparently?

for f in $(find /sys/devices/virtual/net/br-lan/lower_wlan*/ -name hairpin_mode) ; do printf $f:  ; cat $f ; done
/sys/devices/virtual/net/br-lan/lower_wlan0-1/brport/hairpin_mode:0
/sys/devices/virtual/net/br-lan/lower_wlan0/brport/hairpin_mode:0
/sys/devices/virtual/net/br-lan/lower_wlan1-1/brport/hairpin_mode:0
/sys/devices/virtual/net/br-lan/lower_wlan1/brport/hairpin_mode:0

And if I change it to 1 like that all devices are able to ping each other:

for f in $(find /sys/devices/virtual/net/br-lan/lower_wlan*/ -name hairpin_mode) ; do echo 1 > $f ; printf $f:  ; cat $f ; done
/sys/devices/virtual/net/br-lan/lower_wlan0-1/brport/hairpin_mode:1
/sys/devices/virtual/net/br-lan/lower_wlan0/brport/hairpin_mode:1
/sys/devices/virtual/net/br-lan/lower_wlan1-1/brport/hairpin_mode:1
/sys/devices/virtual/net/br-lan/lower_wlan1/brport/hairpin_mode:1

Setting it all back to 0 reproduces the problem...