Balance 20 DHCP server serving on two subnets !?

Hello everyone,

we have a balance 20 on production for about a year without any problem up to now. A few days earlier, some of our ip phones using dhcp started getting ip on subnet instead of the one configured in the balance 20 We first thought we had a rogue dhcp server on the LAN but after some investigations we just saw that the peplink seemed to be the source of the problem. Since we could ping the problematic dhcp server (, we ran wireshark to get the interface mac address which is indeed the balance 20 LAN…

How could this happen ? We are running 5.4.9 firmware which does not allow to have two different subnets…

Can anyone help with this ?

This is not possible on 5.4.9 firmware and even on 6.x firmware it would need to be configured with a proper switch.
Is it only the IP phones this is happening too? If so maybe someone is pushing a changed config to them or something. Do you manage the phones?


Balance does not support multiple subnets on 5.4.9. The only way they would be able to get a 1.1 address is if the subnet mask on the LAN of the Balance is a /21 or lower.

Appreciate if you could enable remote assistance and provide the SN of the device via a support ticket and we can take a closer look.

I know that, but still this is happening as my network capture shows… We manage the phones, they just do a dhcp request and have been working for a year.

I’ve just turned on the remote assistance and opened a ticket. Thanks for the help.


is it normal that i didn’t get any confirmation by mail of the opened ticket ?


Confirmed ticket was opened. Our support team will follow up accordingly.

Thank you.