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Cisco Bug: CSCvs91593 - offer is dropped in data vlan with dhcp snooping using dot1x/mab

Last Modified

Sep 01, 2020

Products (1)

  • Cisco Catalyst 9200 Series Switches

Known Affected Releases


Description (partial)

Issue is seen in the following topology:
- voice client connected to the switch directly
- data client connected behind the phone
- voice client is not capable of CDP

When dhcp snooping and dot1x/mab is enabled, DHCP offer is dropped in data vlan. 

Following sequence will be observed : 

- client mac is placed to voice domain
- client switch sends discovers in untagged vlan
- offer is received from server
- offer is dropped

End devices (specifically phones) that uses data and voice vlan
Dot1x/Mab is used
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Bug Details Include

  • Full Description (including symptoms, conditions and workarounds)
  • Status
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  • Known Fixed Releases
  • Related Community Discussions
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