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Dual DHCP and Static MAC Confusion

SFOS 16.05.0 RC1

I set up two DHCP on a 4 lan port micro pc, assigned one to port 2 (x.x.0.20 to .80) and the other to port 3 (x.x.0.131 to .200)

I mapped the MAC of the ND (new device) to be connected in DP2 (DHCP Port 2) Static details and left the ND to get IP from DHCP.

When I plugged the ND in port 2 - it did not get the IP assigned, in fact it got something worse standard 169.254.238.10 or basically didn't get anything from the DP2.

I then removed the Static MAC from DP2, then ND showed its IP as 0.131!! So DHCP on Port 3 is assigning the IP on my Port 2? I am confused!

 

So DHCP only works for it's identified range and doesn't give IP for those listed in Static MAC mapping?

Is there a way to have a device in the DHCP range so it gets all the DNS and other configuration but will remain at the IP I want so I can find it easily?

Or should I just use my SynoDSM as DHCP which allows IP locking and fixing within the dynamic range and connect on Port 2, and have it assign to those devices connection on Port 3? If so do I need some additional DHCP relay configuration or will it just happen?

 

Newby- Stephen



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Parents
  • Stephen,

    can you share the DHCP screenshot configuration? Did you set the DHCP option to global from console?

    system dhcp static-entry-scope global

    Thanks

  • I did not set the DHCP global option from console.

     

    I have done it now,

    But it is assigning .131 and not .100 per the MAC address.

     

    UPDATE 1:

    Moved Static MAC to 5 AP and it assigned .100 but only after reducing the range of the dynamic IP so 131 wasn't available.

     

    UPDATE 2:

    Yes the other DHCP options such as DNS and Gateway are being shared to the Static MAC devices not like before.

    But why is the DHCP assigned to Port 3 doing IP allocation on Port 2, is it the order of DHCP in the list or what?

Reply
  • I did not set the DHCP global option from console.

     

    I have done it now,

    But it is assigning .131 and not .100 per the MAC address.

     

    UPDATE 1:

    Moved Static MAC to 5 AP and it assigned .100 but only after reducing the range of the dynamic IP so 131 wasn't available.

     

    UPDATE 2:

    Yes the other DHCP options such as DNS and Gateway are being shared to the Static MAC devices not like before.

    But why is the DHCP assigned to Port 3 doing IP allocation on Port 2, is it the order of DHCP in the list or what?

Children
  • Steven,

    I am quite sure that you cannot have 2 DHCP server releasing the same IP addresses/subnet (/24) on 2 different ports.

    What IP are set on Port 3 and 2?

    Same subnet?

    If the answer is yes, it will not work.

    If you need multiple port to share IP/subent, bridge them.

    Regards