Prevent IP conflicts in VMs

javii

Member
Feb 27, 2013
26
2
21
Hi!

I was wondering who do you prevent your users to conflict their IPs in VMs. In CTs you assign the IPs and the users cannot change it, but in VMs the user can use the IP of another user and make an IP conflict.

I suppose this can be solved with VLANs but this network model will be more complex and you will lose IP addresses.

Regards
 
Why not simply use DHCP-only? Al reasent distributions will by default assign IP using DHCP if a DHCP server is available on the network which means users will not have to bother with configuring network under initial load. If you need specific IP's for specific clients you can make IP reservations on the DHCP server -> reserve a specific IP to a specific MAC.
 
You could use something like ebtables to make sure that the bridge you are using doesn't forward traffic for unwanted src-ip from a specific interface.
It would be a problem though from the fact that the tap interfaces gets added to the bridge only on startup of VM ( obvious ofc ), but I guess
you can make a script that gets triggered at VM startup that inserts a rule in the bridge firewall..
 

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