It is running latest openwrt version: 25.12.2.
It was configured diferently, but a few days ago I reset its configuration,
and I followed the dumb AP documentation
The network is simple:
internet <--- gateway (wan+lan+wifi+DHCPd) <---> AP (lan+wifi) <---> laptop
Gateway is a GL-iNet device running GL-iNet firmware.
AP is Comtrend AR-5387un (target: bmips/bcm6328) running OpenWrt 25.12.2
Laptop is linux.
I also have a DNS server in another host, but I don't think it is relevant here.
My problem: connect to AP's wifi after being connected to GW's wifi.
Connection is ok, but AP's bridge does not work as expected:
From inside the AP (ssh): I can ping lan and wan hosts.
Laptop connected to the AP via eth: I get IP, I can ping lan and wan hosts.
Laptop connected to the AP via wifi: I do NOT get IP.
Laptop connected to the AP via wifi, using static IP: I can ping the AP, but nothing else.
Also:
Laptop connected to the GW via wifi always works: I get IP, I can ping lan and wan hosts.
Test 1:
Laptop disconnected for a couple minutes
Connect to GW: all ok
Conect to AP: NOT ok (as described above)
Test 2:
Laptop disconnected for a couple minutes
Conect to AP: all ok
Connect to GW: all ok
Conect to AP: NOT ok (as described above)
The problem shows up when I connect to the AP after being connected to the GW.
If I wait disconnected long enough, it works.
Please connect to your OpenWrt device using ssh and copy the output of the following commands and post it here using the "Preformatted text </> " button (red circle; this works best in the 'Markdown' composer view in the blue oval):
Remember to redact passwords, VPN keys, MAC addresses and any public IP addresses you may have:
By default, the router has 4 lan interfaces only. No wan interfaces (wan was vdsl, I guess).
In the past I have segregated one of them as wan, creating a vlan for it, but not for this dumb ap installation.
I noticed the wan area exists in the firewall configuration, but when you reset the router’s configuration, wan/wan6 interface don’t get created. And I have not added them.
Just to make sure everything upstream is working properly, unplug the cable from port lan4 and connect it to a computer instead. Does that device get an IP address via DHCP?
If that works, plug the cable back into port lan4 and then connect your computer to one of the other lan ports (lan1-lan3) and check to see if it gets an IP.
If ethernet works all around, that means the issue is related to the wifi config, and we can dig deeper into that.
I think I have narrowed the problem a bit.
Thank you maelkoth72 for your PM that made me put order in my thoughs.
In one of my tests I set a static IP to the laptop and connect to AP. I can ping AP, but nothing past it. This combined with the GW logs that show DHCPREQUEST arriving and DHCPOFFER being sent out, leads me to believe this is a layer 2 problem. Mac address cache or proxy arp?
So I timed how long the laptop needs to be disconnected from GW's wifi before it can connect successfully to AP's wifi.
I thought it was in the couple minutes range... but it happens to be 1minute.
Not sure if they are related, but linux (and openwrt) have a default aging time of 60 seconds before an ARP entry is considered stale by the kernel and will have to be revalidated before using it.
There's nothing in your config that would be likely to cause these problems, so I can't quite explain what is happening.
That said, from time to time we have seen cases where something unknown is causing an issue like this... the fastest and easiest way to fix it is often to re-flash the router -- resetting to defaults during that process - and then setup as a bridged AP again.
Grab the standard/default sysupgrade image and install it. Uncheck the "keep settings" box (or use the -n argument on the CLI) so that the system resets to default.
I have nothing to loose and 25.12.3 is almost out.
But I don't have a lot of faith on it, because that's how Installed it only a week ago.
I'll cross fingers while flashing it, LOL.
When you move from the GW to the AP via wireless, the laptop's (wireless card) MAC address moves to another (wired, not wireless) interface member of the GL-iNet bridge, so you need to wait for the GL-iNet bridge aging time to expire.
The laptop's ethernet port has a different MAC address than the wireless interface, so it always works.
Run on the GL-iNet brctl setageing <bridge_name> 0 to see if it makes a difference.
Not specifically, no.
The device has a default 25.12.2 configuration + official openwrt documentation for bridgedap applied manually + a little script that I use to do some basic "system" configuration (hostname, https, theme, etc.).
