I set up the ER605v2 running 2.1.2 as a DHCP server in the LAN (managed by OC200 running 5.7.6)

We run into regular IP conflicts because the DHCP server on ER605 seems to assign same IP address multiple times.

 

I investigated 2 occurences:

 

I noticed an IP conflict in the LAN because our Samsung TV wouldn't connect to the internet.

Upon further investigation, I noticed a MacBook on our LAN had the same IP address as the TV. (both devices set to DHCP)

A disable-enable of the MacBook wifi adapter, and a reconnect of the Samsung TV via the Omada app solved the issue.

 

A few days later, a Windows laptop wouldn't acquire an IP address. Even after multiple disable-enables of the WLAN adapter.

Upon investigation using wireshark, I noticed the laptop sending multiple DHCP decline messages to the ER605, because it kept offering a duplicate IP address already assigned to the Samsung TV.

 

I can SEE the assignment of the IP address to the TV in the client list on the Omada app, but still the DHCP tries to assign the IP address a second time. This in itself is strange behaviour.

But the handling of DHCP decline messages is what striked me too.

Whenever a client sends a DHCP DECLINE on an OFFER, the DHCP server should try to assign another IP address instead of continuously trying to assign the same IP over and over again.

 

Is this a known issue and maybe already on the radar of the support team?

 

I haven't run into the issue since about a week, but will try to gather detailed logs from a new encounter.

 

Best regards,

_RDJ