etliche DHCP offers zur selben MAC

valbuz99

Hallo
Ich habe eine USG50 seit längerem im Einsatz. Nun stelle ich fest, dass es alle paar Minuten einen DHCP offer gibt mit derselben IP und MAC.
Diese MAC hat jedoch bereits eine IP bezogen. Trenne ich nun diesen Endgerät vom Netz passiert dasselbe mit einem anderen Endgerät. Es kann also nicht am Endgerät sein.
Kennt jemand ein solches Verhalten?
Danke
Pat

USG_User

An DHCPOFFER will normally only sent by DHCP server after receiving a DHCPDISCOVER from client host.

Did you tried to capture the entire DHCP traffic on the affected port?

Recently we discovered problems with our USG110 WAN port where the USG react with a DHCPREQUEST instead of a new DHCPDISCOVER after receiving a DHCPNAK from ISP DHCP server (https://community.zyxel.com/en/discussion/11360/usg110-dhcp-discover-failed-on-wan1-port/p1 ).

But in the meantime Zyxel fixed it by FW update.

At that time we put a managed switch in between, mirroring the entire traffic to another port and filtered for all DHCP traffic by WireShark. Then we are able to see where the problem came from.

USG_User

An DHCPOFFER will normally only sent by DHCP server after receiving a DHCPDISCOVER from client host.

Did you tried to capture the entire DHCP traffic on the affected port?

Recently we discovered problems with our USG110 WAN port where the USG react with a DHCPREQUEST instead of a new DHCPDISCOVER after receiving a DHCPNAK from ISP DHCP server (https://community.zyxel.com/en/discussion/11360/usg110-dhcp-discover-failed-on-wan1-port/p1 ).

But in the meantime Zyxel fixed it by FW update.

At that time we put a managed switch in between, mirroring the entire traffic to another port and filtered for all DHCP traffic by WireShark. Then we are able to see where the problem came from.

valbuz99

Hi.
Thanks for reply.
i will try by wireshark.
pat