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On OSX 10.7.3, VirtualBox, using bridged adapter. Everything on the networking side works perfectly as expected in some networking environments, like my home router and some cafes. In others, I can't get an IP address over DHCP, and I don't know why. I suspect there is some setting on the router that is preventing me, or I have some issue with my MAC adress.

When it's not working, in syslog, I'll see a few DHCPDISCOVER messages as my VM tries to find a DHCP server, and after a while, "No DHCPOFFERS received"

And when I go to a "good" router, a simple "service network restart" is all I need to get an IP.

Any ideas?

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migrated from Sep 27 '12 at 16:35

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If they have a landing page that you need to sign into or otherwise authenticae through then I would lean towards MAC filtering of some sort. – Melikoth Sep 27 '12 at 16:57

Some security obnoxious WiFi routers filter based on MAC to help prevent spoofing MAC addresses.

You can change the MAC entirely on Virtual Box.

You can also change the MAC on OS X. (see halfway down the discussion board, key is making sure you aren't on a WiFi network at the time)

Then... here is what I would try:

First, try to change the MAC to a 'real' MAC address from an actual vendor. The first three bytes are vendor driven (in other words a 'Dell' computer will have a Dell vendor ID). Pick a real vendor ID, then just add some made up bytes after it:

If this does not work, also try changing your Apple Airport's MAC and then changing the MAC on VirtualBox.

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I did try a new MAC on VirtualBox, but by using the "refresh MAC" icon there, not by generating a pseudo-real one. I'll try that next time. I'm fairly certain you're right and it's some sort of MAC spoofing limiting thing, but I don't know the mechanism. Perhaps the router blacklists by default VirtualBox's range of generated MACs? I'm actually looking forward to trying all of these options, and seeing if this is the issue. – ezrock Sep 28 '12 at 17:13
entirely possible. It's likely some kind of fancy Cisco AP with anomaly based MAC filtering security, similar to this:… – EdH Sep 29 '12 at 16:41

I have same issue but resolve it in different way. My Android tablet get assigned same IP as VM from router. In router log I see:


and router sent response:


but VM doesn't get this packet...

After cleaning ARP table to tablet and VM in router WEB interface I able to use network adapter in bridged mode (I also reconnect tablet)!

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