Repeater DHCP Issues

[penguin22]

Any updates on this?

I have a RT-AC86U with the same symptoms. (Clients attempting to connect over 2.4GHz are not receiving their DHCP addresses, but 5GHz works with no problems)

The strange part is that I bought this unit and set it up (as an AP) back in July, and it's been working fine until about two days ago.

I wasn't getting anywhere with the Asus code (stock or Merlin) as a Media Bridge. I went back to using my EA-N66U MB and it worked, but had security risk due to age and no further support, along with the issue where the router doesn't see devices individually, affecting QOS, reporting (e.g. in Skynet and Diversion), etc. The trade-off of not having it fail regularly was still worth the sacrifices though.

I then took my RT-AC68P and loaded DD-WRT as a test and was able to run as a Client Bridge without the DHCP issues, though is has the same limitations as the EA-N66U with the router showing, "17 clients are connecting to RT-AC86U through this device." This has the limitations as highlighted above, but is stable at least.

 

[Sparhawk]

I wasn't getting anywhere with the Asus code (stock or Merlin) as a Media Bridge. I went back to using my EA-N66U MB and it worked, but had security risk due to age and no further support, along with the issue where the router doesn't see devices individually, affecting QOS, reporting (e.g. in Skynet and Diversion), etc. The trade-off of not having it fail regularly was still worth the sacrifices though.

I then took my RT-AC68P and loaded DD-WRT as a test and was able to run as a Client Bridge without the DHCP issues, though is has the same limitations as the EA-N66U with the router showing, "17 clients are connecting to RT-AC86U through this device." This has the limitations as highlighted above, but is stable at least.

Thanks!

I contacted Asus support (outside the in-store return window) and they issued an RMA number. So I guess I'll see what state things are in when it comes back from them. Hopefully they replace the 2.4GHz radio or the whole unit.

Seems like the 2.4GHz radio is just faulty because it worked fine for months. Could be some weird issue with their code as well I suppose.

I'll update with their diagnosis in a few days/weeks. Fingers crossed?

 

[Sparhawk]

Thanks!

I contacted Asus support (outside the in-store return window) and they issued an RMA number. So I guess I'll see what state things are in when it comes back from them. Hopefully they replace the 2.4GHz radio or the whole unit.

Seems like the 2.4GHz radio is just faulty because it worked fine for months. Could be some weird issue with their code as well I suppose.

I'll update with their diagnosis in a few days/weeks. Fingers crossed?

Update!

They sent back a new/refurbished unit.
All working for me now again. (Running latest stock firmware for now)

Might be a production/hardware/radio problem with this model.

 

[qtranq]

Any updates on this? any help or advice would be appreciated

I my RT-AC68U in repeater mode with the similar symptoms.
Clients or RT-AC68U (repeater mode) can not get DHCP from Motorola MG7550 router over 2.4GHz or 5GHz.

They all works fine with static ip or older firmware list below

My config connection ISP == MG7550 router/modem )) (( AC68U repeater/media bridge )) (( any Client

network environment
MG7550 ip 192.168.0.1/24 gw 192.168.0.1 dns 192.168.0.1/8.8.8.8

RT-AC68U DHCP, rt-ac68u and client NOT get DHCP ip from router

RT-AC68U ip 192.168.0.2/24 gw 192.168.0.1 dns 192.168.0.1/8.8.8.8, rt-ac68u connect to router, BUT client NOT get DHCP ip from router



DHCP IP request stop work

AC68U (repeater/media bridge) request DHCP IP stop work
firmware Merlin >= 384.6
firmware ASUS >= 3.0.0.4.384.21045



WORK, NO problem with request DHCP IP

AC68U (repeater or media bridge)
firmware Merlin <= 384.5
firmware ASUS <= 3.0.0.4.384.20648

AC68U also work with
firmware DDWRT v3.0-r33555 (Repeater Bridge node)

 

[john9527]

Upgrade to the latest 384.8 builds...there are dnsmasq and routing fixes when running in a non-router mode.

 

[qtranq]

Upgrade to the latest 384.8 builds...there are dnsmasq and routing fixes when running in a non-router mode.

Tried 384.8 and latest 384.8_2 both NOT work. Also try official ASUS 3.0.0.4.384.45149 NOT work too!!

Perhaps I missing some setting in dnsmasq/wifi portion ?

Merlin 384.5/asus 3.0.0.4.384.20648 or devicse use static IP working fine, maybe some routing issue? ASUS Airmesh function create problem with repeater/media bridge

Also when use 384.8 build. I run route command, the default gateway take some delay time completed showing the routing table.

 

[PSP91]

Any help Would be grateful

Asus RT-AC66U
Wireless Router Mode
Version 384.8_2

System Log constantly like this

Dec 28 22:27:17 dnsmasq-dhcp[14098]: DHCPREQUEST(br0)
Dec 28 22:27:17 dnsmasq-dhcp[14098]: DHCPACK(br0)
Dec 28 22:27:41 dnsmasq-dhcp[14098]: DHCPREQUEST(br0)
Dec 28 22:27:41 dnsmasq-dhcp[14098]: DHCPACK(br0)
Dec 28 22:28:36 dnsmasq-dhcp[14098]: DHCPREQUEST(br0)

it does this all day for each device can be like up 30 times for each device each day instead of the set once every 24hrs

also things connected via 2.4GHz dont seem to be issues an IP lease

hopefully someone can help

Thanks

 

[ViperJS]

I know this is an ancient thread but I just wanted to chime in, I had the exact same issue recently with a RT-AC86U that drove me insane. We have a fortigate firewall connected to the internet and serving as DHCP server for the LAN and multiple wireless routers setup in access point mode connected to the fortigate. It worked fine for 8+ months and then one day with no other changes on the network decided to stop passing DHCP responses to client. Sometimes if I rebooted the Asus a multiple times or let it sit for hours it would start passing the responses again, additionally if I manually configured address, gateway, etc on the clients they would work fine. It seemed to affect android, OS X and IOS devices most frequently.

I ran simultaneous tcpdumps/packet traces from the fortigate firewall and the wireless client and saw exactly what others reported -- the DHCP Request makes it to the Fortigate, fortigate replies immediately but the wireless client never receives the response packet. And then you can see the client send request again every X seconds. Interestingly looking at the traces from the client side there is other multi-cast and certain traffic making it to the client, just not from the fortigate, additionally it looks like some other broadcast traffic is affected ie. I see clients repeatedly arp'ing for routers MAC, but never get a reply.

I upgraded firmware, rebuilt config from scratch, etc, none of which resolved the issue or it would atleast appear again after some number of hours or days.

I bought an identical asus router, configured it and plugged it in and it worked flawlessly... I sent the old one back for RMA, will be interesting to see what they say. I can't phathom what component could fail and only block broadcast traffic.