Problem - logged out: lost dhcp lease

RouterOS General
1

I upgrade OS from 6.20.to 6.24 on CCR1009-8G-1S-1S+, I found the problem that there are many times users are forced to log out by lost dhcp. The log info show:

“logged out: lost dhcp lease”

After looking into detail of log it shows the dhcp deassigned “IP” form “MAC address” before it lost dhcp lease and then log out:

“dhcp1 deassigned 192.168.182.XX from C4:56:FE:3B:F1:XX”

and sometime the dhcp reassign IP back to this MAC address again after lost immediately.

Although, the lease time is still enough and not reach the expire…

ALL detail of log

“dhcp1 deassigned 192.168.182.xx from C4:56:FE:3B:F1:xx
userx (192.168.182.xx): logged out: lost dhcp lease
dhcp1 assigned 192.168.182.xx to C4:56:FE:3B:F1:AF”

“dhcp1 deassigned 192.168.182.xx from 70:72:0D:63:8F:xx
usery (192.168.182.xx): logged out: lost dhcp lease
dhcp1 assigned 192.168.182.xx to 70:72:0D:63:8F:xx”

Could the support tell me what is the cause of this problem and how to solve it ?
Or anyone found the same problem, please advise me how to fix it?

Is it possible to downgrade or upgrade only dhcp package?
Is it possible to downgrade or upgrade only dhcp package?
2

Anybody know how to solve this problem?
Even I upgrade OS to 6.25, this issue still exists.

Thank you.

3

What does your DHCP config look like. Are you using RADIUS?

4

I use RADIUS only for userman.

The DHCP config is very basic.

Flags: X - disabled, I - invalid 
 #   NAME     INTERFACE     RELAY           ADDRESS-POOL     LEASE-TIME ADD-ARP
 0   dhcp1    LAN                           hs-pool-11       1h         yes