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kikigak
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DHCP all zeros 00:00:00:00:00:00 on MAC address

Tue Sep 01, 2020 5:10 am

I am using hotspot and have enabled built-in virtual SSID on hAP AC2 with VLAN 70 and have UAP-AC-M VLAN 70, both have the same SSID.
---------------------------------
hAP AC2
SSID: privateWiFi
NETW: 10.0.80.0/24
VLAN: default

vSSID: publicWiFi
NETW: 10.0.70.0/24
VLAN: 70
---------------------------------
UAP-AC-M
SSID: publicWiFi
VLAN: 70
---------------------------------
If the client is in the middle range of publicWiFi SSID, it will get another 2nd ip address then secs/min later 00:00:00:00:00:00 will be the mac address of the 2nd ip address and then cannot browse the internet.

Log: dhcp, warning Detected conflict by ICMP response for 10.0.70.72

What configuration need to do?
 
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FiiMitch
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Re: DHCP all zeros 00:00:00:00:00:00 on MAC address

Tue Sep 01, 2020 8:10 am

Could you do:
/interface wireless print
And paste here.
 
kikigak
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Re: DHCP all zeros 00:00:00:00:00:00 on MAC address

Tue Sep 01, 2020 12:54 pm

I've tried ti change the Multicast Helper to FULL on vSSID if this can fix.

Here's the output.
[admin@MikroTik] > /interface wireless print 
Flags: X - disabled, R - running 
 0  R name="wlan-2G" mtu=1500 l2mtu=1600 mac-address=54:8C:5D:4F:AB:D1 arp=enabled 
      interface-type=IPQ4019 mode=ap-bridge ssid="privateWiFi" frequency=2447 band=2ghz-b/g/n 
      channel-width=20mhz secondary-channel="" scan-list=default wireless-protocol=802.11 
      vlan-mode=no-tag vlan-id=1 wds-mode=disabled wds-default-bridge=none wds-ignore-ssid=no 
      bridge-mode=enabled default-authentication=yes default-forwarding=yes 
      default-ap-tx-limit=0 default-client-tx-limit=0 hide-ssid=no security-profile=profile1 
      compression=no 

 1  R name="wlan-5G" mtu=1500 l2mtu=1600 mac-address=56:8A:4A:7C:B6:C2 arp=enabled 
      interface-type=IPQ4019 mode=ap-bridge ssid="privateWiFi 5G" frequency=5180 
      band=5ghz-a/n/ac channel-width=20/40mhz-XX secondary-channel="" scan-list=default 
      wireless-protocol=802.11 vlan-mode=no-tag vlan-id=1 wds-mode=disabled 
      wds-default-bridge=none wds-ignore-ssid=no bridge-mode=enabled 
      default-authentication=yes default-forwarding=yes default-ap-tx-limit=0 
      default-client-tx-limit=0 hide-ssid=no security-profile=profile1 compression=no 

 2  R name="wlan-v70" mtu=1500 l2mtu=1600 mac-address=3B:8C:56:64:A8:D2 arp=enabled 
      interface-type=virtual master-interface=wlan-2G mode=ap-bridge ssid="publicWiFi" 
      vlan-mode=use-tag vlan-id=70 wds-mode=disabled wds-default-bridge=none 
      wds-ignore-ssid=no bridge-mode=enabled default-authentication=yes default-forwarding=no 
      default-ap-tx-limit=0 default-client-tx-limit=0 hide-ssid=no security-profile=default 
[admin@MikroTik] > 
Last edited by kikigak on Tue Sep 01, 2020 12:55 pm, edited 1 time in total.
 
kikigak
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Re: DHCP all zeros 00:00:00:00:00:00 on MAC address

Tue Sep 08, 2020 5:58 am

still not working.
 
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mkx
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Re: DHCP all zeros 00:00:00:00:00:00 on MAC address

Tue Sep 08, 2020 8:53 am

Log: dhcp, warning Detected conflict by ICMP response for 10.0.70.72

This indicates an IP address conflict. How things work: DHCP client requests a DHCP lease. DHCP server decides upon IP address to lease and (optionally) checks if the IP address is in use (it may use ICMP echo request to do it). If check is fine (no host returns ICMP echo reply), then DHCP server offers IP address to client. Client again performs check if IP address offered is in use. And only if that check is fine it starts to use the assigned address (thus finishing DHCP handshake).

The above quoted log might indicate that server detected that it selected (and not yet assigned) address which is already in use. This is not a problem per-se, DHCP server in this case selects another IP address from pool (if a free address is available) ... but it does indicate there's a problem in your network. Either it might be due to DHCP server loosing its state (restarted before writing out lease information) or due to rogue device (uses IP address from pool without acquiring it from DHCP server) or due to another (rogue?) DHCP server present in network ... or due to buggy client device (if it tries to renew the lease but fails to indicate this in DCHPREQUEST message and then replies to server's checks ... or if it tries to re-use previously used address (lease expired in the mean time) and again answers to server's checks).

BTW, I doubt multicast helper can really help to make DHCP exchange more reliable. Multicast helper acts on packets sent to broadcast MAC address ... DHCP packets are exchanged between unicast MAC entities (client with known MAC address, but without valid IP address, and DHCP server ... only initial DHCP DISCOVER packet, sent from DHCP client, has broadcast MAC address set as destination, but that packet is not handled by multicast helper as well because most of time DHCP server is wired and multicast helper only works when AP is transmitting broadcast packets over wireless, not when it's receiving them).
 
janda
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Re: DHCP all zeros 00:00:00:00:00:00 on MAC address

Thu May 13, 2021 3:50 pm

i have the same issiue when there is more than eg.: 50 clients connected on guest wifi network
Detected conflict by ARP response for 10.10.10.104 from E6:46:46:DF:51:ED
in log

and 00:00:00:00:00:00 on MAC address in DHCP Server Leases (as conflict)

What is the correct ARP settings on guest bridge and guest wifi interface?

Guest users deassigned and assignet too often i things too :(
disconnected, group key exchange timeout
this occurs only if many users are conenected in same time

is the multicast helper the right solution on this
Last edited by janda on Thu May 13, 2021 4:06 pm, edited 1 time in total.
 
erlinden
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Re: DHCP all zeros 00:00:00:00:00:00 on MAC address

Thu May 13, 2021 3:59 pm

Besides SSID, do both accesspoints have identical security settings?
 
janda
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Re: DHCP all zeros 00:00:00:00:00:00 on MAC address

Thu May 13, 2021 4:11 pm

you means security profile?
then yes, but differences only on wpa2 pre shared key, the rest settings are same
guest wifi is virtual 2.4ghz
local is physical wlan1 2.4ghz

in log are
disconnected, group key exchange timeout

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