BugZero | Cisco BugID CSCwb43548 - 9800: disable "ip proxy-arp" by default

Cisco - Defect ID: CSCwb43548

9800: disable "ip proxy-arp" by default

Cisco - Defect ID: CSCwb43548

9800: disable "ip proxy-arp" by default

Last updated on June 17th, 2025

BugZero Risk Score
6.1 Medium

Overall: 6.1

Severity: 6.4

Lifecycle: 9.1

Popularity: 4.6

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Bug Details

Views: 80

Description

Symptom

- The 9800 responds to wired and wireless client ARP broadcasts with its own MAC address causing traffic disruption. - The 9800 ewlc has to be configured with an SVI on the client VLAN - On the Router arp table you will find the 9800 SVI mac address as source

Conditions

The 9800 ewlc has to be configured with an SVI on the client VLAN

Workaround

Configure "no ip proxy-arp" on the interfaces where you don't want the 9800 to send its proxy ARP responses.

Further Problem Description

Traffic disruption has been seen in customer networks due the default nature of the feature

Change history

2025-06-17 Added: 17.3.4c

Links

Original Vendor Announcement

Relevant Products

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Affected versions:17.3.4c

Fixed versions: 17.10.1, 17.10.1a, 17.10.1b, 17.11.1, 17.11.1a, 17.12.02a, 17.12.1, 17.12.1a, 17.12.1w, 17.12.1x, 17.12.1y, 17.12.1z, 17.12.1z1, 17.12.1z2, 17.12.1z3, 17.12.1z4, 17.12.2, 17.12.2a, 17.12.3, 17.12.3a, 17.12.4, 17.12.4a, 17.12.4b, 17.12.5, 17.12.5a, 17.13.1, 17.13.1a, 17.14.1, 17.14.1a, 17.15.1, 17.15.1a, 17.15.1b, 17.15.1w, 17.15.1x, 17.15.1y, 17.15.2, 17.15.2a, 17.15.2b, 17.15.2c, 17.15.3, 17.15.3a, 17.16.1, 17.16.1a, 17.17.1

Relevant Products

Click on a version to see all relevant bugs

Affected versions:17.3.4c

Fixed versions: 17.10.1, 17.10.1a, 17.10.1b, 17.11.1, 17.11.1a, 17.12.02a, 17.12.1, 17.12.1a, 17.12.1w, 17.12.1x, 17.12.1y, 17.12.1z, 17.12.1z1, 17.12.1z2, 17.12.1z3, 17.12.1z4, 17.12.2, 17.12.2a, 17.12.3, 17.12.3a, 17.12.4, 17.12.4a, 17.12.4b, 17.12.5, 17.12.5a, 17.13.1, 17.13.1a, 17.14.1, 17.14.1a, 17.15.1, 17.15.1a, 17.15.1b, 17.15.1w, 17.15.1x, 17.15.1y, 17.15.2, 17.15.2a, 17.15.2b, 17.15.2c, 17.15.3, 17.15.3a, 17.16.1, 17.16.1a, 17.17.1

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Cisco Integration

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Cisco - Defect ID: CSCwb43548

9800: disable "ip proxy-arp" by default

Cisco - Defect ID: CSCwb43548

9800: disable "ip proxy-arp" by default

Last updated on June 17th, 2025

BugZero Risk Score6.1 Medium

Bug Details

Symptom

Conditions

Workaround

Further Problem Description

Links

Top Cisco Defects

Ready to prevent the next vendor outage?

BugZero Risk Score
6.1 Medium