Static DHCP mapping issues

[Denko]

I have an RT-86U and because of various reasons ended up starting to use Merlin on it. Works ok'ish but lately I haven't been able to add anymore DHCP mapped devices (may have been the latest firmware or one before that.) Once I hit update the DHCP table it just sits there for ever and if I try to connect again the whole webserver on the router is gone (some other pages on the wifi side experience the same thing. Obviously the change doesn't take) I have about 30 in the list... and I believe I saw somewhere the limit was ~256.

Note that the device (2nd of my RT-86U and both have the same issue) does not work on the 2.4 GHz band in any shape way or form.

Anyhow... what info am I missing? Is the DHCP mapping expected to be like that?

 

[ColinTaylor]

I have about 30 in the list... and I believe I saw somewhere the limit was ~256.

No, the size of the list is is severely limited, especially on the RT-AC86U. What firmware version are you running? There was a change in 384.13 that increased the size of the list.

384.13 (31-July-2019)
  - CHANGED: dhcp_staticlist no longer contains hostnames, these
             have been moved to dhcp_hostnames for better
             compatibility with upstream and closed source
             components, also allows more static leases to be
             defined before reaching the size limit.

 

[Denko]

I am using the firmware for RT-AC86U @ 384.13.0 Can you elaborate on "especially on the RT-AC86U" as I need a couple of more reasons before I throw my two units into the garbage.

 

[ColinTaylor]

Using 384.13 I would have thought you would be OK. The very early firmware versions only allowed for very small lists (~35 IIRC). Merlin increased that so prior to 384.13 the number of entries was about 70 (assuming fairly short host names). With 384.13 it has increased again.

It's possible that the conversion from the old way of storing the names to the new got screwed up somewhere. @Xentrk has written a utility that can backup, restore, clear, size check, and even increase the DHCP entries.

https://www.snbforums.com/threads/dhcp_staticlist-and-dhcp_hostnames-utility.58957/

 

[PolarBear]

And maybe make sure that the host names do not contain any illegal characters.

Some characters are problematic (there was a thread about this somewhere).

I use only letters, numbers and minus signs and that works ok for me.

 

[Denko]

Thanks for all the replies. I factory reset it and reconfigured everything from scratch. It seems to work a whole lot better now. Cheers!