primalmotion/Archipel — Issue #392: Archipel UI sets NAT device to 'lo' (and breaks NAT)
Author: jvburnes
Created: 2012-01-18 19:39:33+00:00
State: open

When editing the default network, the Archipel UI sets the NAT device to 'lo' by default. This obviously breaks NAT behavior in Linux because it causes the generation of bad firewall rules.

UI Version: Archipel UI Version 0.4.0-41ca131 (Vesta)

Setup/Verification: I didn't remember ever specifying the NAT gateway device in either Archipel or any other interface. To verify this use-case I checked some of my old backups of the /etc/libvirt/qemu/networks/default.xml and found that 'dev' had never been set. This means that Archipel UI replaced the default with whatever the first entry in the dialog was (maybe the first device returned by some Linux query).

In any case, opening the dialog and setting it to 'eth0' is a logical workaround. Once I had done that the problem was solved. It may have not even required a libvirt restart. (Check your 'default.xml' network configuration and iptables rule list to be sure)

Suggestions:

Option 1: Check the current state of of 'dev' in the network. If it's not in use, don't set it.
Option 2: Create separate editing dialogs for the network/NAT interface and another one for the DHCP reservations so you know what you are editing.