On Wed, Oct 26, 2011 at 01:37:08AM +0200, Hans van Kranenburg wrote: > Perhaps it's best to consider the devices set up by ovs at boot time > equal to the nics that are physically present in a server. Using > this approach, I can just say "Yay, I have a switch built in to my > server where I can plug in virtual machines!" (as if it were a > physical hardware thing). Seems rather like a way of thinking you > did want to achieve with this project anyway. ;] > > - Basic configuration of the switch takes place at the time I > install my (e.g. Xen dom0) server. (yes, I can make changes later) > - OVS makes sure it will restore the configured setup when I reboot > the machine. > - I can just use the 'normal' way of setting up links and > configuring ip addresses and network routing using the ifupdown > tools. Although it's not perfect, until now I've been able to > perfectly abuse ifupdown and its hooks to do everything I wanted to > do to set up and tear down interface configuration. (Note: this will > *require* the 'networking' init script to be run *after* ovs sets up > the devices!)
I mainly like the ideas behind this approach (I have considered similar approaches before), but there are some difficulties. A technical difficulty is that OVS installs many files under /usr, but the Filesystem Hierarchy Standard that Linux distributions follow says that /usr is supposed to be shareable, that is, it should be possible for a number of machines to mount it from a network share. This means that files in /usr must not be needed to mount a network share. Hence, OVS must not put anything in /usr. Fine; we could move files elsewhere. This solution raises an organizational difficulty: /bin, /sbin, /lib, etc. are supposed to be reserved for programs essential to booting only. I have not yet felt up to the task of arguing that ovs-vswitchd, ovsdb-server, ovs-dpctl, and so on in fact fall into this category. Maybe it would not be a difficult hurdle to cross, or maybe it would be, but I haven't done it yet. > I'd also like, (I you agree) to ask the current maintainer of > ifupdown in Debian (newsflash! someone is actually putting effort > into ifupdown in Debian right now!) about his thoughts about these > issues. Please feel free to ask him. You can CC me or ovs-discuss, if you like. Thank you for raising these issues. _______________________________________________ discuss mailing list discuss@openvswitch.org http://openvswitch.org/mailman/listinfo/discuss
