I have an RB751 running 5.12, and I'm hitting this particular issue.

I have a macbook and a mac mini, both connecting via wifi.

If I want to vnc (or access anything remotely) from my macbook to my mac mini, I have to first log into the RB751 and ping the mac mini before the mac mini responds to anything from my macbook.

The mac mini isn't loosing connectivity, because I can walk in to the room where it's at when the macbook can not connect, and the mini is still connected and can use the network just fine. But, the macbook just cant' access it. Again, as soon as I ping the mac mini from the RB751, I can get to the mac mini again just fine.

I'm not %100 sure that it's not an issue with the mac machines, but, it's looking more like some kind of ARP issue?

Anyone come across something like this before? And hopefully have a fix for it?

Just an update. I didn't experience any more issues after updating to 5.18. Recently updated to 5.19, and still no issues.