Intermittent issues with Bridged Adapter

[yribbens]

Hello,

I'm currently running Virtual Box 4.3.12 on top of Mac OSX 10.9.2

On multiple VM's i'm experiencing issues where the network connection drops (just stops working after a period of 15 or 20 minutes). If I ping a random IP address, for example 8.8.8.8 I receive the error message "destination host unreachable". Only unable to ping external addresses using bridged adapter.

Please advise.

[noteirak]

"destination host unreachable" means you are missing routes for that specific IP. Maybe the card was disconnected in the host? or maybe some power saving options turn it off.
In any case, I would dig deeper - you provide no valuable info I am afraid. You want to start with Minimum information needed for assistance - include the guest settings too.

[loukingjr]

assuming noteirak is on to something as to power saving features, on your Mac, right click on the VirtualBox icon>Get Info>check "Prevent App Nap". See if that helps.

[montdidier]

I had the same issue on Macosx 10.9.5 and Virtualbox running Ubuntu 14.04 as hosted. I am using a Thunderbolt ethernet adapter as the bridged adapter. I experimented heavily. What fixed it for me in the end seemed to be trying a different virtual adapter. I am using PCFast III. I am not convinced entirely that it is the adapter change that fixed the problem as I also notice the connection speed has changed from gigabit to 100 mb/s. So I have a hypothesis that perhaps it is speed related. I will try with a gigabit adapter set to a slower rate and see if it I also get success.