02-10-2024 12:26 AM
hi all
in my workplace on 1 of all switches in our network, clients and phones don't get ip address from dhcp server in network, only works with ip static.
The rest of the clients and phones on other switches can get ip address from dhcp server without problem.
switch model is C2960X.
Please help me to solve this problem, thanks.
02-10-2024 12:48 AM
Do you use dhcp snooping?
MHM
02-10-2024 01:06 AM
yes, dhcp snooping on other switches works well. I even changed the switch But it still didn't work.
02-10-2024 01:57 AM
If So' then check
1- the port toward DHCP server must config as trust
2- no ip routing in non-work SW
3- make sure the dhcp server understand op82' if not disable add op82 in non-work SW
Check above points
MHM
02-10-2024 02:41 AM
All these were checked
02-10-2024 02:44 AM
02-10-2024 01:21 AM
switch model is C2960X.
how is this switch configured ? Layer 2 only, Does switch have Layer 3 interrace ?
if layer 3 interface on the switch - make sure you added ip helper address of DHCP Server to get DHCP IP from DHCP Server
can you post the configuration of the switch (by removing password information)
02-10-2024 01:59 AM
no without any layer3 interface only layer2 interface.
configuration of all switches are same.
02-10-2024 02:03 AM
As you mentioned connecting with Static IP works and DHCP not working
If this is Layer 2 switch - i would like to see the configuration - Do you have more VLAN - trunk has any native VLAN ?
02-10-2024 02:21 AM - edited 03-13-2024 12:01 AM
ok
config file...
02-10-2024 02:43 AM
All port as I see (sorry of I miss it if there is) are config without dhcp trust?
How dhcp server work if port not config witg dhcp trust.
MHM
02-10-2024 02:51 AM
trunk port is trust which connect to other switches and dhcp server but access ports do not need to be trusted because those are connected to endpoints. we only define limite rate for access ports.
02-10-2024 03:02 AM
Correct'
Show interface trunk <- share this
Show dhcp snooping <- share this
02-10-2024 04:56 AM
As per the config i do not see any issue -
what DHCP server you using, what the IOS code which working vs what is IOS code which is not working ?
show port-security interface x/x there the device connect not getting the IP.
show ip dhcp snooping
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