RT-AC68U DHCPREQUEST(br0) DHCPACK(br0) ???

[Vipermk2]

I've just completely defaulted my RT-AC68U due to numerous disconnection issues with any firmware since 3004-378-4585. I've also used the Merlin 380.57 version and getting some strange log events, something that I've not seen before and wonder what it is thats causing it. I also have a RT-N66U and using it as a Repeater.

Feb 21 15:04:18 dnsmasq-dhcp[9541]: DHCPDISCOVER(br0) xx:xx:xx:xx:xx:17
Feb 21 15:04:18 dnsmasq-dhcp[9541]: DHCPOFFER(br0) 192.168.1.16 xx:xx:xx:xx:xx:17
Feb 21 15:04:18 dnsmasq-dhcp[9541]: DHCPREQUEST(br0) 192.168.1.16 xx:xx:xx:xx:xx:17
Feb 21 15:04:18 dnsmasq-dhcp[9541]: DHCPACK(br0) 192.168.1.16 xx:xx:xx:xx:xx:17 android-addd
Feb 21 15:04:43 dnsmasq-dhcp[9541]: DHCPDISCOVER(br0) xx:xx:xx:xx:xx:f4
Feb 21 15:04:43 dnsmasq-dhcp[9541]: DHCPOFFER(br0) 192.168.1.28 xx:xx:xx:xx:xx:f4
Feb 21 15:04:43 dnsmasq-dhcp[9541]: DHCPREQUEST(br0) 192.168.1.28 xx:xx:xx:xx:xx:f4
Feb 21 15:04:43 dnsmasq-dhcp[9541]: DHCPACK(br0) 192.168.1.28 xx:xx:xx:xx:xx:f4 android-9655c

This is just a small section of the log but seems to be filling up every few minutes with the same devices.
I defaulted the router through the browser before I updated the Firmware but noticed it remembered my sign in details so I pressed the reset button on the back for 5 secs then everthing was factory default. I also have an active wireless MAC Filter

 

[ColinTaylor]

This is quite a common behaviour. Some mobile devices keep coming out of "sleep" mode, to check for emails, updates, etc. My Sony android TV does it all the time! Very annoying.

 

[Vipermk2]

So you are saying this is normal, I just never saw it happen so frequently before. Is it a feature in newer firmware?

 

[jegesq]

My understanding is that this is known issue, and is caused by the network map polling for devices. As Sanna1967 says, you can hide the DHCP queries from showing up in your log, but the router will keep polling for devices anyway.

 

[ColinTaylor]

These messages have been reported many times, particularly by Apple users. So much so that Merlin added the option to suppress them! (thanks @Sanna1967)

The interaction between wireless devices is always unpredictable, with different chipsets and drivers. So it's possible that the current firmware uses an updated wireless driver that doesn't work well with your devices (phones?).

Try deleting and recreating the wireless profiles on the phones to see if that helps.

 

[Vipermk2]

These messages have been reported many times, particularly by Apple users. So much so that Merlin added the option to suppress them! (thanks @Sanna1967)

The interaction between wireless devices is always unpredictable, with different chipsets and drivers. So it's possible that the current firmware uses an updated wireless driver that doesn't work well with your devices (phones?).

Try deleting and recreating the wireless profiles on the phones to see if that helps.

Thanks for all your replies I have disabled the displaying of them thanks Sanna1967, I will do as you suggest Colin as soon as I have access to all the devices.

 

[ColinTaylor]

@jegesq This sounds different from the "network map" problem. IIRC that only occurs once an hour.

@Vipermk2 My phone does something similar. Sometimes it will create those message every couple of minutes for 12 hours, and then for no reason just stop doing it.

 

[jegesq]

@jegesq This sounds different from the "network map" problem. IIRC that only occurs once an hour..

@ColinTaylor: You may be right, but I believe the network map issue causes these inquiries more often than once an hour. My AC3200 running Merlin 380.57 at home usually has anywhere from 16-28 devices connected (depending on who is doing what), and devices that are not being used generally poll more often than every hour, and other devices that are in use, poll more frequently. Pulling up the network map "list" view from the GUI shows that it is rebuilding itself (i.e., it refreshes) every couple of minutes. My system logs have tons of similar "DHCPDISCOVER" and "DHCPREQUEST" lines, which run almost continuously. And btw, I have absolutely no disconnect issues as mentioned by the OP. Again, my understanding was that these were the result of the router polling devices in order to keep the network map up to date.

In another thread earlier today, another user complained that his printer used to only wake up "every hour" but is now waking up at "every 1 minute" intervals. Merlin responded and noted that this was a "known issue with network map". See, http://www.snbforums.com/threads/problems-with-rt-ac66u-and-hp-m680dn.30562/

 

[ColinTaylor]

In another thread earlier today, another user complained that his printer used to only wake up "every hour" but is now waking up at "every 1 minute" intervals. Merlin responded and noted that this was a "known issue with network map". See, http://www.snbforums.com/threads/problems-with-rt-ac66u-and-hp-m680dn.30562

Actually that's not what was said in that thread. If you re-read his slightly broken English he's reporting it waking up at 1 minute past each hour.

 

[jegesq]

Colin:

Right you are. Didn't catch the digital time read outs in his post first time around. So if the DHCPDISCOVER and DHCPREQUEST calls are unrelated to the network map, what are they related to? I believe you said above that they are caused by mobile devices checking for emails, and other things. Every single one of my devices has been seen responding to these, not just mobile. I can understand the frequency of some of my computers that are all now running Windows 10 what with the telemetry inherent therein, but I'm sort of surprised that I'm seeing these for a 7 year old Denon AV Receiver (it gets internet radio and updates firmware via Ethernet...it's connected to my network via an RT-AC66U running as a wireless media bridge.

I still believe the queries also in some way interact with the Network Map in the GUI, otherwise, why would the map rebuild itself so often...it's not like these devices are disconnecting and then reconnecting, so something else must be going on.

 

[ColinTaylor]

I don't know, but we might be seeing multiple issues here.

...it's not like these devices are disconnecting and then reconnecting, so something else must be going on.

In my case, that's exactly what's happening. YMMV. All the times I've seen this is for devices that were in "sleep/standby/powersave" mode. They appear to wake up, connect, do something and then go back to sleep.

My TV does it continuously while it's "off", but not at all when it's on.

I have a access point (non-ASUS) that logs connection attempts so I can see that just prior the every DHCP request there is a corresponding re-association with the AP.