hello;
dhcp server not obtain ip address to wireless device & lan devices.
this problem from 2 last week.

help me please.

According to wiki: https://wiki.mikrotik.com/wiki/Manual:I ... properties

busy = this address is assigned statically to a client or already exists in the network, so it can not be leased

Since it is not really usual to have so many devices which would claim addresses like this, I assume there is/was some particular device which responds to all ping and arp requests. According to RFC2131 DHCP server SHOULD check whether IP is available before leasing it. In mikrotik implementation this check is done by simple ping (ICMP echo request). To do a ping, ARP request must be successfully completed as well.

It is quite hard to guess what could be wrong. I think easiest way to debug this situation is run ARP ping and look at what MAC address is responding: (please replace the interface name with correct name where your addresses are bound. From the screenshot it is impossible to figure out rest of your config)

Another approach might be a look in your ARP table, where some of these IP addresses should be visible (and should have same MAC address assigned) or run normal ping and look at packet sniffer results.

Once you get MAC, you should be able to figure out what device is causing this and theoretically track it through your network and find it.

You like working in the dark vecernik87?? Vampire?

For the OP, please post your config.
/export hide-sensitive file=yourconfigmarch

You like working in the dark vecernik87?? Vampire?

For the OP, please post your config.
/export hide-sensitive file=yourconfigmarch

<ot>Vampire? Absolutely! Looking forward to suck your tasty bodily fluids! </ot>

I don't believe there is any way to misconfigure ROS to cause this. Since we don't have a "dst-nat" on output chain, it has to be another device which receives and answers those ARP/ICMP requests, which in the end block DHCP server from offering IP addresses.
I would much more appreciate more info about the network, instead of config. Anyway, recommended steps should give OP chance to track down the source and figure it out. (obviously, depending on his knowledge of networking)

When lease shows mac as 00:00:00:00:00 then a device already has that IP.

Some Ideas:
- Turn on logging for the DHCP topic.
- If log says Offering Lease without Success, check out this thread: viewtopic.php?f=2&t=130176&p=719332&hil ... cp#p719332
- Possibly another DHCP server on network that hands out DHCP a little quicker? To test this, run packet sniffer on the router, or Wireshark on your PC. Capture DHCP only. Release and renew your IP. How many DHCP Servers respond? Or disable the Mikrotik DHCP Server and release/renew your IP. Does it get an IP?
- An Arp ping will tell you the mac address. If you do an arp-ping on different in-use IPs, do they have the same mac address? If so, maybe a rogue device/software on the network.