Preview Tool

Cisco Bug: CSCur13400 - DHCP Option 82 and Sub Option 5 issue in WLC 8.0

Last Modified

Sep 11, 2019

Products (1)

  • Cisco 5500 Series Wireless Controllers

Known Affected Releases

8.0(100.0) 8.0(110.0)

Description (partial)

Support is added for Cisco WLC to include Option 82, Sub-Option 5 when
relaying the DHCPDiscover message from the client. The Sub-Option 5 defines
the subnet, thereby allowing the GIADDR to only have one job, being just
the relay source, the address that the relay agent can be reached at. The
relay source can be any IP on the Cisco WLC that can easily be reachable
from the DHCP server, for example the management interface IP.

The pre-8.0 DHCP relay used the client facing dynamic interface to relay
the DHCP packet, which requires the DHCP-Server to be reachable from the
Client Subnet. My understanding is that this option allows me to set a
different interface (for example the management interface) as the source of
the DHCP packet.

Disregarding the DHCP Payload, only focusing on the IP-Packet the
controller generates itself the source is set to the correct interface
(management), but the source-MAC and the VLAN it is emitted on is set to
the client facing dynamic interface. In other words

Define WLC option 82 and sub option 5

Related Community Discussions

8.0MR3 Beta Availability
8.0.122.x Available - 8.0MR3 Beta 8.0MR3 ( is now posted, the beta process is closed. Thanks for all the feedback! Resolved Caveats CSCtl96208 capwap ap hostname CLI returns "ERROR!!! Command is disabled." CSCtu45614 Spectrum Management Bit Should be set to 1 all the time CSCul07738 DPAA Tx/Rx stuck; reload due to ethernet interface receive failure CSCum86031 Roaming 5508 to 5760 applies wrong QOS policy on configuring aaa-overrid CSCun12965 Lightweight AP should not send jumbo frame by ...
Latest activity: Apr 01, 2016
Bug details contain sensitive information and therefore require a account to be viewed.

Bug Details Include

  • Full Description (including symptoms, conditions and workarounds)
  • Status
  • Severity
  • Known Fixed Releases
  • Related Community Discussions
  • Number of Related Support Cases
Bug information is viewable for customers and partners who have a service contract. Registered users can view up to 200 bugs per month without a service contract.