Fix Apple Bonjour with Cisco autonomous APs

I purchased some used Cisco C1140 autonomous access points for my home network (autonomous meaning not lightweight or requiring a WLC). While everything seemed to be fine at first, later we noticed that printouts to our Canon laser printer were no longer working from our Macs. After some research I realized that the Macs were failing to locate the printer due to Apple Bonjour protocol issues. Google searches led to partial solutions, but most required a downgrade of the AP IOS – a no, no as a security professional.

I kept looking and it turns out my savior was actually a Chromecast user with the same issue. Two configuration changes on the APs to disable IGMP snooping had to be executed, not one:

All the prior advice was just to disable the former, which didn’t work (at least without an AP downgrade!). Adding the second line did the full trick.

You may need to disconnect and reconnect to the wireless for full effect. Since multicast IGMP has other uses, I can’t guarantee the impact in a larger environment.

UPDATE:

Well, this may or may not work. In the end it seemed not to for me, but it’s still worth a try in your network.

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