More than 230 different models of Cisco Wi-Fi access points may be writing 5MB a day of nonessential data, filling their onboard flash memory to the point at which they lack space for future software updates.
The networking giant revealed the mess earlier this week in an advisory that warns “Certain Cisco Access Points (APs) may fail to download new software images or Access Point Service Packs.”
The reason for the mess is an updated library in Cisco IOS XE – specifically versions 17.12.4, 17.12.5, 17.12.6, and 17.12.6a – which sees access points generate a log file named cnssdaemon.log.
Cisco says that file grows by 5MB every day and can’t be deleted from the command line interface.
“The longer an AP runs the affected software, the higher the probability that a software download will fail due to insufficient disk space,” Cisco warns.
Moving to a version of IOS XE that doesn’t write the log file is the obvious fix, but Cisco warns it’s not that simple because if your Wi-Fi box has filled its flash with junk, it may not have enough internal storage space to hold the updated OS.
If that’s the case, Cisco warns you could end up with a bootloop.
Cisco’s advisory therefore includes a procedure to test for the presence of the offending IOS XE releases, and instructions on how to sort things out.
The advisory also lists over 230 models of Cisco access points that run the rotten versions of IOS XE.
The Register is certain all readers running Cisco Wi-Fi kit will have accurate and recently-updated inventories of your access point fleets and can therefore swiftly identify and remediate hardware that needs attention. Those of you who don’t have that info at hand doubtless inherited a mess from a slovenly predecessor and now get to be the hero who tidies things up.
While you’re at it, you may also wish to consider another issue Cisco identified which relates to voicemail synching issues that may arise once Microsoft shuts down Exchange Web Services. ®
Source: The register