DHCP not working with WIFI isolated mode

Installing and Using OpenWrt Network and Wireless Configuration
1

Hello

My dhcp is working as expected:

Tue Sep  1 07:56:20 2020 daemon.info dnsmasq-dhcp[2238]: DHCPDISCOVER(br-VLAN_10) 18:fe:34:e1:43:a1
Tue Sep  1 07:56:20 2020 daemon.info dnsmasq-dhcp[2238]: DHCPOFFER(br-VLAN_10) 192.168.10.6 18:fe:34:e1:43:a1
Tue Sep  1 07:56:20 2020 daemon.info dnsmasq-dhcp[2238]: DHCPREQUEST(br-VLAN_10) 192.168.10.6 18:fe:34:e1:43:a1
Tue Sep  1 07:56:20 2020 daemon.info dnsmasq-dhcp[2238]: DHCPACK(br-VLAN_10) 192.168.10.6 18:fe:34:e1:43:a1 GA-em-szoba-node1

when i switch on WIFI ISOLATED mode i getting the following error:

Tue Sep  1 07:48:58 2020 daemon.info dnsmasq-dhcp[2238]: DHCPDISCOVER(br-VLAN_10) 18:fe:34:e1:43:a1
Tue Sep  1 07:48:58 2020 daemon.info dnsmasq-dhcp[2238]: DHCPOFFER(br-VLAN_10) 192.168.10.6 18:fe:34:e1:43:a1
Tue Sep  1 07:48:58 2020 daemon.info dnsmasq-dhcp[2238]: DHCPREQUEST(br-VLAN_10) 192.168.10.6 18:fe:34:e1:43:a1
Tue Sep  1 07:48:58 2020 daemon.info dnsmasq-dhcp[2238]: DHCPNAK(br-VLAN_10) 192.168.10.6 18:fe:34:e1:43:a1 wrong server-ID

I can still ping some of the client but most of them not clients are aging out from /var/dhcp.leases

I wonder what would be the problem?, how can i resolve this meanwhile still keeping client isolation?

Thank you

2

Are you sure it's related to client isolation?looking at those logs, I would not say that. Perhaps the issue is somewhere else, and this option just makes it more visible?

1 Like
3

I think this 2 setting

  • Domain required: Don't forward DNS-Requests without DNS-Name
  • Authoritative: This is the only DHCP in the local network

Conjection with WIFI ISOLATED mode causing this.
I just wonder why?

4 
tcpdump -vni br-VLAN_10 udp port 67
1 Like
5

Please, post your complete DHCP configuration.

1 Like
6

I not really sure now. I put back everything almost to the original setting and no problem (i left the expire value in infinity). i like consistency and this is not that.
Actually yesterday when i changed this there was no any problem just discovered it in the morning and it is remain after reboot.

config dnsmasq
        option localise_queries '1'
        option rebind_protection '1'
        option rebind_localhost '1'
        option expandhosts '1'
        option readethers '1'
        option leasefile '/tmp/dhcp.leases'
        option resolvfile '/tmp/resolv.conf.d/resolv.conf.auto'
        option localservice '1'
        option local '/GyA19a/'
        option domain 'GyA19a'
        option domainneeded '1'
        option authoritative '1'

config dhcp 'lan'
        option interface 'lan'
        option ra_slaac '1'
        list ra_flags 'managed-config'
        list ra_flags 'other-config'
        option ignore '1'

config dhcp 'wan'
        option interface 'wan'
        option ignore '1'

config odhcpd 'odhcpd'
        option maindhcp '0'
        option leasefile '/tmp/hosts/odhcpd'
        option leasetrigger '/usr/sbin/odhcpd-update'
        option loglevel '4'

config host
        option name 'GA-em-GySz-lampa01'
        option dns '1'
        option mac 'DC:4F:22:F8:24:27'
        option ip '192.168.10.4'
        option leasetime 'infinite'

config host
        option name 'GA-RFbridge'
        option dns '1'
        option mac '84:0d:8e:66:28:c3'
        option ip '192.168.10.3'
        option leasetime 'infinite'

config host
        option name 'GA-em-viz-uv'
        option dns '1'
        option mac '84:f3:eb:3e:a5:bb'
        option ip '192.168.10.2'
        option leasetime 'infinite'

config host
        option name 'GA-F-Dolgozo-node1'
        option dns '1'
        option mac '18:FE:34:D4:87:01'
        option ip '192.168.10.5'
        option leasetime 'infinite'

config host
        option name 'GA-em-szoba-node1'
        option dns '1'
        option mac '18:FE:34:E1:43:A1'
        option ip '192.168.10.6'
        option leasetime 'infinite'

config host
        option name 'GA-WS-monitor1'
        option dns '1'
        option mac '5c:cf:7f:86:3e:c3'
        option ip '192.168.10.7'
        option leasetime 'infinite'

config host
        option name 'GA-WS-monitor2'
        option dns '1'
        option mac '5c:cf:7f:c0:58:c2'
        option ip '192.168.10.8'
        option leasetime 'infinite'

config host
        option name 'GA-k-vilagitas'
        option dns '1'
        option mac '5c:cf:7f:c0:b8:07'
        option ip '192.168.10.9'
        option leasetime 'infinite'

config host
        option name 'GA-F-Dolgozo-lampa01'
        option dns '1'
        option mac 'C8:2B:96:43:8B:A7'
        option ip '192.168.10.10'
        option leasetime 'infinite'

config dhcp 'VLAN_10'
        option interface 'VLAN_10'
        option start '100'
        option limit '150'
        option leasetime '12h'
        list dhcp_option '42,192.168.10.1,192.168.10.254'
        option force '1'