Can't add Static DHCP entry any more - Merlin 382.1/RT-AC86U

[ggbal]

Has 20 entries in the static DHCP table. Wanted to add another one. Once you add that (clicking "+" sign"), I could see that new entry in the table below. But after I click "apply", that entry disappeared after the completion.

Merlin 328.1
RT-AC86U

Anyone has seen the same problem and knows the fix?

 

[JDB]

Just do it again. I saw it a couple of times


Sent from my iPhone using Tapatalk

 

[ggbal]

Did it multiple times. I even went to the network map and used MAc to IP binding over there. But once it was applied, the DHCP table still doesn't show that entry. Is there a nvram command to bind it using the command line?

 

[RMerlin]

What is the current length of your dhcp_staticlist nvram?

nvram get dhcp_staticlist

382 has nvram length validation to protect against buffer overruns, and the RT-AC86U has some of these hardcoded in closed-source components so I can't increase their maximum length.

 

[ggbal]

It fixed in 382.1_2. Thanks, RMerlin.

 

[RMerlin]

It fixed in 382.1_2. Thanks, RMerlin.

Thank Asus. They have moved the dhcp_staticlist variable to a file, allowing them to reach the full 2500 characters limit.

 

[Kevin K]

Do I still use the same old nvram get/set for dhcp_staticlist, or did moving it to a file change the way I should update it?

Something changed. I just submitted an nvram set dhcp_statulist, and my router went into a reboot loop. I had to reset it to factory defaults with the reset button.

 

[RMerlin]

Do I still use the same old nvram get/set for dhcp_staticlist, or did moving it to a file change the way I should update it?

It's transparent to the user,the libnvram function will automatically address the connect location when using the nvram user tool.

 

[Kevin K]

I might have found what changed. I have this item (among others) in dhcp_staticlist

• <50:9a:4c:ba:bc:bc>192.168.8.82>susanpc

and I have these items in /jffs/configs/dnsmasq.conf.add

• dhcp-host=50:9a:4C:ba:bc:bc,192.168.8.82,susanpc
  
  
• dhcp-host=34:f6:4b:72:80:a3,192.168.8.83,susanpc

I'm now seeing this in my logs:

• dnsmasq[2540]: FAILED to start up

It used to be OK to have dnsmasq.conf.add override dhcp_staticlist, but sometime in the last few months, this appears to have become illegal. I'm using dnsmasq.conf.add because I have a PC with an Ethernet and a WiFi NIC and I want that PC to have the same DNS name regardless of the interface but different IP addresses.

Which brings me to the question: Since I have to put some of my DHCP+DNS entries in dnsmasq.conf.add, is there any reason I shouldn't move ALL of my items from dhcp_staticlist to dnsmasq.conf.add?

 

[JDB]

dhcp-host=50:9a:4C:ba:bc:bc,34:f6:4b:72:80:a3,192.168.8.82,susanpc

This might help?

Sent from my iPhone using Tapatalk

 

[Martineau]

I might have found what changed. I have this item (among others) in dhcp_staticlist

• <50:9a:4c:ba:bc:bc>192.168.8.82>susanpc

and I have these items in /jffs/configs/dnsmasq.conf.add

• dhcp-host=50:9a:4C:ba:bc:bc,192.168.8.82,susanpc
  
  
• dhcp-host=34:f6:4b:72:80:a3,192.168.8.83,susanpc

Which brings me to the question: Since I have to put some of my DHCP+DNS entries in dnsmasq.conf.add, is there any reason I shouldn't move ALL of my items from dhcp_staticlist to dnsmasq.conf.add?

I believe prior to Firmware v382.x, '/etc/ethers' was created from the NVRAM dhcp_staticlist and dnsmasq.conf contained a directive ?

read-ethers /etc/ethers

Now under v382.x, the dhcp_staticlist is merged directly into '/etc/dnsmasq.conf', using dhcp-host= statements, so you now end up with possible duplicate entries when '/jffs/configs/dnsmasq.conf.add' is appended to the end of '/etc/dnsmasq.conf'