Mac DNS and wi-fi troubles

After my work laptop was stolen and I switched to an older Mac Mini, my wi-fi internet connection would cut out frequently but somewhat intermittently. The OS would still show as connected, but nothing would load. It was very frustrating as a developer.

When cutting out, it would not disconnect from our messaging server properly, so I would still show up as available to others, and messages would get lost.

It was a fresh install of the OS (El Capitan), so I was surprised. I tried to search for the problem, and tried various fixes, to no avail. I wrote a shell script to disconnect and reconnect the wi-fi, which would also reestablish the internet connection:

networksetup -setairportpower en1 off
networksetup -setairportpower en1 on

After some time, I came to realize that it would only cut out when visiting my local development server, something I do frequently. So I modified my behavior to accommodate, doing local development in batches and disconnecting from messaging beforehand. This was kind of a pain, and proved particularly difficult for projects with remote scripts or curl calls.

I looked at my Apache server settings and tried tweaking things, but that didn’t help. I also had problems with other local servers.

Just recently, I discovered that I only had the problem when visiting via the domain that my computer was broadcasting over the network. Macs will broadcast a name, like tobys-computer.local, over the local network for various sharing purposes. We use that to let others in the office see what we’re working on. I used it locally just so I could more easily grab and share the links. But no more.

I’ve been using localhost or other domains set up in /etc/hosts, and haven’t had the problem since. I’m not sure why the problem was occurring, but this solution is sufficient, a very minor inconvenience. Work is now much easier and less stressful.