Creating multiple nics with --nic (and quantum) orders NICs randomly
| Affects | Status | Importance | Assigned to | Milestone | |
|---|---|---|---|---|---|
| OpenStack Compute (nova) |
New
|
Undecided
|
Unassigned | ||
Bug Description
Description:
When creating a machine on multiple networks with the nova command line, one does
nova boot --image ed8b2a37-
(http://
You expect to get the NICs attached to the VM in the same order (device 0 = first net listed, and so on, which - since they are usually all the one device type - corresponds with eth0, eth1, ... in Linux). (Apparently this promise is not in that documentation, but I had it previously confirmed verbally from a core dev.)
However, the guarantee is not always kept. In a two nic machine, NICs sometimes get attached in reverse order. Specifically seen with libvirt.
Analysis:
This is probably not an issue for many users. If you're using DHCP on both interfaces, you'll get appropriate address and route setups and may not care which interface is on which network. If, however, DHCP is turned off, or you're attached to two provider networks, it's not possible to distinguish which network is which, so the ordering is required.
Crap. Literally 2 minutes after having pressed 'save' someone else pointed me to the same, fixed, bug in quantum. See bug 1064524. Just verifying if that patch is applied in the 2 trees I'm working with.