OpenWrt - Dumb AP - IP Problem

[Tropaion]

Hello,
I have an Ubiquiti AC AP Pro with OpenWRT which I configured according to the dumb ap guide (https://openwrt.org/docs/guide-user/network/wifi/dumbap)
I set the the IP adress of the ap to 192.168.88.2 and the Gateway, which is my Mikrotik Router with RouterOS to 192.168.88.1.
At the beginning it is working fine and I can access the webinterface of openwrt but after a some time or after a reboot, the IP cant be found anymore. But internet access via AP is working always fine.
Now in RouterOS, I discovered that the IP 192.168.88.2 is never leased or documented somewhere. I also tried to set a static Ip to the mac of the AP, but it doenst work either, the AP doesnt get found even though the internet connection is working.
What is there the problem?
Im trying and searching for many days now but cant find the problem.

Thanks and greetings,
Tropaion

[trendy]

What is the output of:

uci show network
uci show wireless
ip -4 addr
ip -4 ro

Use preformatted text </> when you paste the copied output of the Ubiquity.

[Tropaion]

root@OpenWrt:~# uci show network
network.loopback=interface
network.loopback.ifname='lo'
network.loopback.proto='static'
network.loopback.ipaddr='127.0.0.1'
network.loopback.netmask='255.0.0.0'
network.globals=globals
network.globals.ula_prefix='fd1f:ed68:116a::/48'
network.lan=interface
network.lan.type='bridge'
network.lan.ifname='eth0.1'
network.lan.proto='static'
network.lan.netmask='255.255.255.0'
network.lan.ip6assign='60'
network.lan.ipaddr='192.168.88.2'
network.lan.gateway='192.168.88.1'
network.wan=interface
network.wan.ifname='eth0.2'
network.wan.proto='dhcp'
network.wan6=interface
network.wan6.ifname='eth0.2'
network.wan6.proto='dhcpv6'
network.@switch[0]=switch
network.@switch[0].name='switch0'
network.@switch[0].reset='1'
network.@switch[0].enable_vlan='1'
network.@switch_vlan[0]=switch_vlan
network.@switch_vlan[0].device='switch0'
network.@switch_vlan[0].vlan='1'
network.@switch_vlan[0].ports='2 0t'
network.@switch_vlan[1]=switch_vlan
network.@switch_vlan[1].device='switch0'
network.@switch_vlan[1].vlan='2'
network.@switch_vlan[1].ports='3 0t'
root@OpenWrt:~# uci show wireless
wireless.radio0=wifi-device
wireless.radio0.type='mac80211'
wireless.radio0.channel='36'
wireless.radio0.hwmode='11a'
wireless.radio0.path='pci0000:00/0000:00:00.0'
wireless.radio0.htmode='VHT80'
wireless.radio0.country='US'
wireless.radio0.legacy_rates='1'
wireless.radio0.__toggle='Enable'
wireless.default_radio0=wifi-iface
wireless.default_radio0.device='radio0'
wireless.default_radio0.network='lan'
wireless.default_radio0.mode='ap'
wireless.default_radio0.ssid='FlowerHouse'
wireless.default_radio0.encryption='psk2'
wireless.default_radio0.key='iVraPWuEM5jfrCc'
wireless.radio1=wifi-device
wireless.radio1.type='mac80211'
wireless.radio1.channel='11'
wireless.radio1.hwmode='11g'
wireless.radio1.path='platform/qca956x_wmac'
wireless.radio1.htmode='HT20'
wireless.radio1.country='US'
wireless.radio1.legacy_rates='1'
wireless.default_radio1=wifi-iface
wireless.default_radio1.device='radio1'
wireless.default_radio1.network='lan'
wireless.default_radio1.mode='ap'
wireless.default_radio1.ssid='FlowerHouse'
wireless.default_radio1.encryption='psk2'
root@OpenWrt:~# ip -4 addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
5: br-lan: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP qlen 1000
    inet 192.168.88.2/24 brd 192.168.88.255 scope global br-lan
       valid_lft forever preferred_lft forever
root@OpenWrt:~# ip -4 ro
default via 192.168.88.1 dev br-lan
192.168.88.0/24 dev br-lan scope link  src 192.168.88.2

Thanks for your help.

[trendy]

You may want to edit the post above and erase the wireless key.
I don't see any issue with the config.
Make sure that the DHCP server excludes 88.2 from the available IPs or set a static DHCP lease for the mac of the ubiquity to 88.2, regardless of the fact that it has static IP.
Just to be sure, erase the WAN and WAN6 interfaces if you don't use them, and assign both physical ports under the same VLAN1.

[Tropaion]

I already tried to assign a static ip in routeros but the problem is that the router cant find the ap so it doesnt work. I used the mac which is shown in openwrt in the interface br-lan, is that the right one?

[vgaetera]

• Try to configure a different IPv4 address.
• Try to access the device with IPv6 link-local address.
• Check the ARP/NDP caches.

[trendy]

When the problem occurs can you at least ping the IP of the Ubiquity? Or it also doesn't work?

[Tropaion]

I can only ping after if made the IP settings.
After a reboot, I cant access the webinterface and ping anymore.
But the internet over the AP works without problems.

EDIT:
I think I found a not so nice workaround.
I set 192.168.88.2 to a static ip with the mac in RouterOS, even though the Router cant finde the AP and doenst register it, at least the IP wont be given away to others.

[trendy]

If you cannot access the device at all, I am afraid that the only way to troubleshoot furthermore is by connecting serial console. Then you can verify with the same commands if it has an IP address or it is lost somehow.