Introducing SOC Insights for BloxOne Threat Defense: Boost your SOC efficiency with AI-driven insights to eliminate manual work and accelerate investigation and response times. Read the blog announcement here.

NIOS DNS DHCP IPAM

Reply

Repeated discover msgs

New Member
Posts: 2
789     0

hi,



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.

Re: Repeated discover msgs

Authority
Posts: 24
790     0

Renewal should be a DHCPREQUEST Unicast packet ...

 

Specifically which devices are sending a broadcast ?

 

RFC-2131

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.

Showing results for 
Search instead for 
Did you mean: 

Recommended for You

Demo: Infoblox IPAM plug-in integration with OpenStack Newton