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DHCP server assigns wrong netmask

Posted: Thu Jul 26, 2018 9:28 pm
by landersohn
I tried to change my microtik router to a new ip: 10.69.9.1/24. I also changed the pool for the DHCP server accordingly.
I expected when a client connects to get a netmask of 255.255.255.0

Turns out on my linux pc I get 255.0.0.0, on my windows pc I get 255.255.255.255 and I have difficulties doing ssh and broadcasts from one pc to the next.
Dopes anybody know how to configure the DHCP server such that the netmask comes out OK?

Re: DHCP server assigns wrong netmask

Posted: Mon Jul 30, 2018 5:29 pm
by reidavidinho
Why don't u remove the existing dhcp server and the pool, and then create an entirely new one.

Re: DHCP server assigns wrong netmask

Posted: Mon Jul 30, 2018 5:56 pm
by diddie17
It might be optional, but I think it's the /ip dhcp-server network command that sets the netmask in my config, with an entry matching each pool.

It probably should sort itself out as a default, but doesn't look like it is in your example.

From https://wiki.mikrotik.com/wiki/Manual:IP/DHCP_Server
netmask (integer: 0..32; Default: 0) The actual network mask to be used by DHCP client. If set to '0' - netmask from network address will be used.

As an example from my config -
/ip dhcp-server network
add address=192.168.0.0/24 dns-server=192.168.0.3,192.168.0.4 domain=test.com gateway=192.168.0.1 netmask=24 ntp-server=192.168.0.3,192.168.0.4

Happy to be corrected though :-)