We're closing out this incident since network connectivity has been restored to the OS X jobs.
Posted Jul 18, 2015 - 19:24 UTC
Update
We've decided to temporarily migrate back to an old firewall pair. We've seen some network issues with this in the past under high load (which is why we moved off it), but we think it should be able to maintain the traffic while we continue to investigate on the newer pair.
Posted Jul 18, 2015 - 16:37 UTC
Investigating
We've received reports of our firewall being unreachable on our Mac infrastructure, causing no network connectivity for Mac jobs. We're working on resolving this.