Containers Do Not Register with Gateway/DHCP

[devnet]

Hello all.

 

Just put in an entire TP-Link Omada network complete with switches, AP's, Gateway and Controller.  All things went without a hitch.  I have created some VLANS but kept Unraid on my default admin network so it's able to communicate with everything.

 

Here's the issue.  I can get Unraid to register it's IP and I'm able to statically assign it in the Omada interface.  However, only 5 out of my 11 containers register with Omada so I cannot assign static IP's on 6 of them.

 

On the TPLink forums, I've posted topology, etc (hope this is ok to link here):  https://community.tp-link.com/en/business/forum/topic/533610

 

And I'm at a loss for why some containers don't contact my DHCP server and tell it what their IP address is.  Can anyone point me in the right direction?  I'm just waiting for an IP conflict to take down my containers.

[Ford Prefect]

On 2/24/2022 at 5:32 PM, devnet said:

Can anyone point me in the right direction?  I'm just waiting for an IP conflict to take down my containers.

You can manually enable a "dhcp"-range inside unraid for dockers in the docker settings. just make sure, that the pools in your central router and in unraid do not overlap.

 

The current situation is, that it "works as designed", so not a bug or flaw in unraid, but a flaw / misconception on user side on how container networking with dockers work.

 

A Docker is not a complete mini-VM, but just a single app.

Hence a docker creator/maintainer simply does not cater for a dhcp-client inside the container (which then would make aquiring an IP via external DHCP-server work for macvlans - and even ipvlans, (which do not have distinct MACs) when the client issues a requested hostname with the request.

 

This "issue" seems to bother more and more users recently, hence I created that feature request: 

 

...make yourself heard