Guest

Preview Tool

Cisco Bug: CSCvu24785 - "switchport dot1q ethertype 0x88a8" but packets encapsulated in 0x8100

Last Modified

Jul 25, 2020

Products (65)

  • Cisco Nexus 3000 Series Switches
  • Cisco Nexus 3548 Switch
  • Cisco Nexus 93600CD-GX Switch
  • Cisco Nexus 3636C-R Switch
  • Cisco Nexus 92348GC-X Switch
  • Cisco Nexus 9516 Switch
  • Cisco Nexus 3548-X Switch
  • Cisco Nexus 31108TC-V Switch
  • Cisco Nexus 9396PX Switch
  • Cisco Nexus 92304QC Switch
View all products in Bug Search Tool Login Required

Known Affected Releases

9.3(3)

Description (partial)

Symptom:
Ethernet II, Src: 70:6d:15:41:6b:43 (70:6d:15:41:6b:43), Dst: e4:c7:22:dc:f8:01 (e4:c7:22:dc:f8:01)
    Destination: e4:c7:22:dc:f8:01 (e4:c7:22:dc:f8:01)
        Address: e4:c7:22:dc:f8:01 (e4:c7:22:dc:f8:01)
        .... ...0 .... .... .... .... = IG bit: Individual address (unicast)
        .... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
    Source: 70:6d:15:41:6b:43 (70:6d:15:41:6b:43)
        Address: 70:6d:15:41:6b:43 (70:6d:15:41:6b:43)
        .... ...0 .... .... .... .... = IG bit: Individual address (unicast)
        .... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
    Type: 802.1Q Virtual LAN (0x8100) <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Remains 0x8100
802.1Q Virtual LAN, PRI: 0, CFI: 0, ID: 82
    000. .... .... .... = Priority: 0
    ...0 .... .... .... = CFI: 0
    .... 0000 0101 0010 = ID: 82
    Type: 802.1Q Virtual LAN (0x8100)
802.1Q Virtual LAN, PRI: 0, CFI: 0, ID: 10
    000. .... .... .... = Priority: 0
    ...0 .... .... .... = CFI: 0
    .... 0000 0000 1010 = ID: 10
    Type: IP (0x0800)

Conditions:
Trunk port on BCM based n9k/n3k with non-default ethertype setting (0x88a8 or 0x9100) and port is flapped.
Upon port flap on BCM based n9k/n3k, ethertype setting on that port reverts to default =0x8100.
Bug details contain sensitive information and therefore require a Cisco.com 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.