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togo
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Location: Prešov, Slovakia

DHCP Server not assigning IP

Sun Jul 23, 2023 12:56 pm

Hello,

my router (MT hEX) does not assign IP address to my two Windows computers by DHCP server (neither automatically or by setting static lease). I recently upgraded the network cards from 1Gbps to 2.5Gbps in both computers, since then I have to set the IP address manually on both computers. The connection goes through 2 SFP ports + RJ45 modules in the MT Switch CSS326-24G-2S+.

Is there anything to set in the switch OS to make it work?

PS: I can live with manual settings, just asking.

Another question is how to properly set static lease for network devices? I have currently filtered the same device with static (not active - waiting) and dynamic lease (bound).
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mkx
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Re: DHCP Server not assigning IP

Sun Jul 23, 2023 2:17 pm

I don't know anything about SwOS, there might be some settings preventing from DHCP request to pass from client to server. To verify that DHCP requests aftually arrive at router, you can bump up verbosity level of logging for DHCP on the router ... something like this:
/system logging
add topics=dhcp,debug action=memory
Then log should contain lots of information about DHCP requests and replies.


Re. static DHCP leases: while it's possible to set everything by hand, the easiest way is to let DHCP server set a dynamic lease to client. Then you can use GUI to set the lease static (select lease and click "make static"). Afterwards you can make desired changes (e.g. change IP address to be leased) and when client makes attempt to renew the lease, it will get the new settings. Depending on lease validity timers this may take long time so you may want to force client to do the stuff manually (either kick client via OS hooks, whatever the OS you're running on client) or simply disconnect and reconnect network cable of client (which will cause client to re-negotiate DHCP lease).
 
togo
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Re: DHCP Server not assigning IP

Tue Jul 25, 2023 3:57 pm

the easiest way is to let DHCP server set a dynamic lease to client. Then you can use GUI to set the lease static (select lease and click "make static").
Actually, this procedure is exactly what I did, but it doesn't work as I would expect. Somehow there is another lease bound and my static lease is waiting.
 
togo
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Re: DHCP Server not assigning IP

Mon Aug 14, 2023 12:33 pm

the easiest way is to let DHCP server set a dynamic lease to client. Then you can use GUI to set the lease static (select lease and click "make static").
Actually, this procedure is exactly what I did, but it doesn't work as I would expect. Somehow there is another lease bound and my static lease is waiting.
Now it is working correctly. It seems I shouldn't change "Client ID".
 
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mkx
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Re: DHCP Server not assigning IP

Mon Aug 14, 2023 3:27 pm

Now it is working correctly. It seems I shouldn't change "Client ID".
Right, Client ID is THE identification of a client (not MAC address, they usually correlate though) and you should not change it manually ...

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