Network crash

[gmanigault]

I am using Rhel 6.8 with current patches and up to date.

I have virtualbox Version 5.1.8 r111374 (Qt5.6.1)
I have two VMs that i want to run. HEre is the wierd part.

One VM is Windows 7 and the other is Centos 7. I can start either of them separately with no issues. When they are both brought up in bridged adapter mode they crash the whole network. By that I mean my Cisco phone goes off line and reboots. i loose all network connection. Does anyone have any ideas as to why this occurs and how to correct it?


Has anyone had the same issues?

Gary M.

GWShark

[socratis]

my Cisco phone goes off line and reboots. i loose all network connection.

Naive question, but what pn earth does your phone have to do with it? Is that the one providing DHCP addresses to the VM?

[Martin]

Is this a private network or a company network?
My first guess would be a port security setting defined by the admin in a company network switch which doesn't allow so many "systems" on one cable.

[gmanigault]

Well it looks like the cisco phone crashing was a red herring. I tried the same thing at home and my network dumped then also. Can I bring up multiple VM's with a bridged nic? Do I need to configure anything special to give these NICS a pool of ip addresses to work from? Could I start each VM with its own static ip?

[socratis]

You can have as many bridged connections as your host can handle VMs. Nothing special to configure (except maybe your router?). You can have DHCP or static, it's up to you and your router. But, you still don't make sense:

I tried the same thing at home and my network dumped then also.

That tells me squat. Could you be more specific? Forget about what you could or couldn't do and give us full details of what you're actually doing, like IP ranges, your setup, the VMs involved, the symptoms that you see on your network.

I have a feeling that you cloned one or two VMs, you didn't re-initialize the MACs and you're seeing weird problems because you have two identical MACs, which you can't have.