02-09-2023 07:47 PM
I am seeing weird behavior in our network. any end device which is trying to renew IP address sends a Request packet with a Broadcast flag as Broadcast is unable to renew IP address.
any client that is sending it as Broadcast flag as Unicast is able to renew the lease.
since they are not able to renew ip they will keep sending request packets until the lease is expire and then start the discovery process to get new lease.
02-13-2023 10:34 AM
Renewal should be a DHCPREQUEST Unicast packet ...
Specifically which devices are sending a broadcast ?
DHCPREQUEST generated during RENEWING state: 'server identifier' MUST NOT be filled in, 'requested IP address' option MUST NOT be filled in, 'ciaddr' MUST be filled in with client's IP address. In this situation, the client is completely configured, and is trying to extend its lease. This message will be unicast, so no relay agents will be involved in its transmission. Because 'giaddr' is therefore not filled in, the DHCP server will trust the value in 'ciaddr', and use it when replying to the client.
I would suggest a call to Infoblox support with collected packet captures to work out the why.