dhcp client stuck searching forever

RouterOS Beginner Basics
1

Hi all,

I have installed about 60 routerboards during last 18 months.

My RBs have a standard dhcp-client on the eth adapter and are connected to ISP routers.

Some of my routerboards (about 3) has this problem:

I installed it, it worked without problem for months, then they suddenly stuck. Restarting routerboard and the ISP router i can get it works again for some hours or days but the problem returns. Other connection through the ISP router has no problem.

Routerboards simply lost their ip addresses, i notice the dhcp-client status sets on searching forever, logs show no response from the ISP router.

I tried to set up a watchdog which restarts the routerboard when it disconnects from the internet with no luck, after restart the routerboard stuck again in the searching dhcp-client status.

I use the RB411U.

I think it could be some incompatibility issues from routerboards and ISP router, but have you some advice for me? Maybe i can set some settings to avoid this problem? Is there something i don’t know?

Thank you a lot in advance

2

If restarting the router does not help, but restarting the ISP modem fixes it… then the problem is with the modem. Perhaps it only gives out an address on startup with a lease of xx minutes or is otherwise setup improperly?

3

i’ve found this happen to me as well when i tried to place the ether1 into a bridge.
when i removed it from the bridge no more problems

hope this helps

4

I had a similar problem, but I think I found a solution. Instead of setting DHCP Client Interface to the ethernet interface, set it to the bridge interface.

5

if you have an interface set as port of bridge dhcp-client and dhcp-server has to be assigned to bridge interface.