BugZero | Cisco BugID CSCwf37271 - cnssdaemon.log fills up flash partition 2, prevent...

Cisco - Defect ID: CSCwf37271

cnssdaemon.log fills up flash partition 2, preventing AP upgrades

Cisco - Defect ID: CSCwf37271

cnssdaemon.log fills up flash partition 2, preventing AP upgrades

Last updated on July 22nd, 2026

BugZero Risk Score
9.7 High

Overall: 9.7

Severity: 10.0

Lifecycle: 9.1

Popularity: 7.8

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Bug Details

Views: 24

Description

Symptom

Customers using Cisco IOS XE versions 17.12.4, 17.12.5,17.12.6 and 17.12.6a on platforms C9124, C913X, IW916X and CW916X are affected by an issue where cnssdaemon log file in the /storage partition grows continuously This log file can grow approximately 5MB per day (~1.8GB per year uncompressed), which can fill the part2 partition and prevent upgrades when part1 is the active partition. The cnssdaemon.log file in /storage cannot be deleted via the Cisco CLI.

Conditions

AP is 9124/913X/916X AP using 17.12.4, 17.12.5 or 17.12.6, without fixes in APSP

Workaround

None

Further Problem Description

Install APSP for the release with this fix, and check documentation for instructions on how to check AP available storage space before performing an upgrade. See: https://www.cisco.com/c/en/us/support/docs/wireless/wireless-lan-controller-software/225443-validate-and-recover-catalyst-aps-on.html This does not impact 17.12.1 to 17.12.3, or releases 17.13 to 17.18 No other AP models are impacted

Change history

2026-07-22 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-22 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-21 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-21 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-19 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-19 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-19 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-19 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-17 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-17 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-17 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-17 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-16 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-16 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-15 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-15 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-14 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-14 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-13 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-13 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-11 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-11 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-11 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-11 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-09 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-09 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-09 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-09 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-08 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-08 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-07 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-07 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-06 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-06 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-03 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-03 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-03 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-03 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-03 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-03 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-07-02 Added: 17.12.4, 17.12.5, 17.12.6a

2026-07-02 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-29 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-29 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-29 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-29 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-29 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-29 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-26 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-26 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-26 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-26 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-26 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-26 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-25 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-25 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-24 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-24 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-23 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-23 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-22 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-22 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-19 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-19 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-19 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-19 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-19 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-19 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-19 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-19 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-17 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-17 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-16 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-16 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-15 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-15 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-13 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-13 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-13 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-13 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-12 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-12 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-11 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-11 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-10 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-10 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-09 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-09 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-07 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-07 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-07 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-07 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-06 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-06 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-05 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-05 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-03 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-03 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-03 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-03 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-02 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-02 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-06-01 Added: 17.12.4, 17.12.5, 17.12.6a

2026-06-01 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-29 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-29 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-29 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-29 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-29 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-29 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-28 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-28 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-27 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-27 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-26 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-26 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-25 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-25 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-22 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-22 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-22 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-22 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-22 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-22 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-21 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-21 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-19 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-19 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-19 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-19 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-19 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-19 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-17 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-17 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-15 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-15 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-15 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-15 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-14 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-14 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-13 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-13 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-13 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-13 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-12 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-12 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-10 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-10 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-08 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-08 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-08 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-08 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-08 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-08 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-06 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-06 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-05 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-05 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-04 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-04 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-02 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-02 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-02 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-02 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-01 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-01 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-05-01 Added: 17.12.4, 17.12.5, 17.12.6a

2026-05-01 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-04-29 Added: 17.12.4, 17.12.5, 17.12.6a

2026-04-29 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-04-29 Added: 17.12.4, 17.12.5, 17.12.6a

2026-04-29 Removed: ap-17.12.5.2, ap-17.13.0.4

2026-01-15 Added: ap-17.12.5.2, ap-17.13.0.4

Relevant Products

Click on a version to see all relevant bugs

Affected versions:17.12.4, 17.12.5, 17.12.6a

Fixed versions: No known fixed versions

Relevant Products

Click on a version to see all relevant bugs

Affected versions:17.12.4, 17.12.5, 17.12.6a

Fixed versions: No known fixed versions

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Cisco - Defect ID: CSCwf37271

cnssdaemon.log fills up flash partition 2, preventing AP upgrades

Cisco - Defect ID: CSCwf37271

cnssdaemon.log fills up flash partition 2, preventing AP upgrades

Last updated on July 22nd, 2026

BugZero Risk Score9.7 High

Bug Details

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Conditions

Workaround

Further Problem Description

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BugZero Risk Score
9.7 High