DHCP Mis-assignments due to Race Condition between Router and Controller on startup

DHCP Mis-assignments due to Race Condition between Router and Controller on startup

DHCP Mis-assignments due to Race Condition between Router and Controller on startup
DHCP Mis-assignments due to Race Condition between Router and Controller on startup
2024-02-29 22:32:36
Hardware Version:
Firmware Version: 5.13

Noticed a few times now after extended power outages, that some of my device come back with semi random IP's despite the fact that I have IP reservations for them. Most recently the host of my controller came back with a pooled IP instead of its fixed IP, and despite a few attempts to release/renew (dhcpclient -r eth0) I couldn't unstick its newfound IP.  Rebooting the router resolved the issue immediately.  So I'm curious why the router would override a DHCP Reservation, or even if it did, would not then recognize the DHCP request from a known MAC and wrong IP and force the IP change.

<< Paying it forward, one juicy problem at a time... >>
  0      
  0      
#1
Options
2 Reply
Re:DHCP Mis-assignments due to Race Condition between Router and Controller on startup
2024-03-01 03:53:39

  @d0ugmac1 

 

DHCP reservation is set on the router, maybe the settings won't be assigned if you don't reboot the router.

Just striving to develop myself while helping others.
  0  
  0  
#2
Options
Re:DHCP Mis-assignments due to Race Condition between Router and Controller on startup
2024-03-01 12:16:12

@Virgo 

 

If I boot both router and controller from a long period of being powered off, the situation occurs.  I believe this is because the router comes online before my controller, and while it remembers *some* of its settings like subnets and WAN config, it doesn't seem to remember the IP reservations.  Perhaps there is a special case with the controller's IP?  Regardless, if I then reboot the router while the controller is running, all is well (including correct re-numbering of its IP if incorrectly set).  To me that says that the IP reservations are not stored in the persistent memory of the router, but are instead loaded by the controller when the config gets pushed.

<< Paying it forward, one juicy problem at a time... >>
  0  
  0  
#3
Options