On Mon, Feb 26, 2007 at 03:13:04PM +0100, Bertho Stultiens wrote:
Pasi Kärkkäinen wrote: [snip]
- Changes the MAC-address of peth0 to FE:FF:FF:FF:FF:FF. If I have another
physical interface, peth1, can it have the same MAC address, or does it have to be different?
In principle, all unicast MACs in a broadcast domain have to be unique. Each vlan is a broadcast domain, so that is fine. However, the kernel has a slightly different view of the interfaces and I an not sure that it can keep everything properly isolated. The FE:FF..FF addresses are fake anyway and should be local only. There is then the STP problems you can run into depending on whether you have all isolated STP instances for each vlan/interface.
To make a long story short :), use unique MACs to avoid problems. You can use them f.ex. from the 00:01:01, 10:00:00, ac:de:48... (and there are more private MAC pools defined; see http://standards.ieee.org/regauth/oui/oui.txt and look for PRIVATE).
[do not use MAC addresses with an odd numbered high octet; these are reserved for multicast/broadcast]
OK. Thanks.
Because peth* and xenbr* have NOARP, it should be ok to use fake MAC-addresses.. for example:
peth0 FE:FF:FF:FF:FF:00 peth1 FE:FF:FF:FF:FF:01
etc.
Or should I use some of the PRIVATE address ranges from that doc?
- Sets peth0 to NOARP (disables ARP). Why is this? Is it a requirement?
- Sets xenbr0 to NOARP. Same question goes for this.
The NOARP is because you do not want the interfaces to answer to arp requests. Neither interface has an IP address assigned, so they are to be local only and their MAC should not propagate. It is a requirement so far as to have them shut up...
OK.
I have working setup with FC6 network scripts/tools, but I'd like to make sure I do the correct things.
If you also could post your resulting scripts or make a micro-howto, that would be great too. Polishing can be done on the list I guess.
I'll do it after I've tested them properly :)
-- Pasi