gpg: failed to create temporary file '/var/lib/lurker/.#lk0x56e03100.hantslug.org.uk.23432': Permission denied
gpg: keyblock resource '/var/lib/lurker/pubring.gpg': Permission denied
gpg: Signature made Sun Sep 9 18:27:27 2007 BST
gpg: using DSA key 20ACB3BE515C238D
gpg: Can't check signature: No public key
On Sun, Sep 09, 2007 at 06:08:42PM +0100, Damian Brasher wrote:
>
> >> Damian Brasher wrote:
>
> > The real problem is that bridging does not work when you define a unique
> > mac address, but does when you omit a mac address...
> >
>
> don't use macaddr=23:23:23:00:00:01 use something sensible - I used a
> VMware set of fictitious mac's (from a different LAN entirely) and
> increased the value of one byte, i.e 00:50:56:C0:00:F3 seems that Qemu is
> intelligent enough to realise I was making up very unreal mac's.
>
> All working perfectly - running three bridged VM's with no packet loss :-)
Ah, yes. It all comes back to me now. You need to be careful about
the low nibble of the first byte in the MAC. It's got some special
values in it. The description in Wikipedia[1] says that the two
low-order bits in the first byte of the MAC indicate globally/locally
administered addresses, and uni/multicast, with the latter being the
least significant bit of the two.
So your original MAC, ending in 3, is a locally-administered
multicast address, which is probably why it's breaking. Ideally, that
first byte should probably end in 2, 6, A or E, for a
locally-administered unicast interface. The VMWare address is
globally-unique unicast (since VMWare got a manufacturer allocation of
00:50:56).
The University (or at least the department) should probably decide
on a suitable MAC address space (first three bytes of the address) for
local use and manage the allocation of addresses within that space, as
with increasing use of virtualisation, this kind of issue is going to
crop up more often.
Hugo.
[1]
http://en.wikipedia.org/wiki/MAC_address
--
=== Hugo Mills: hugo@... carfax.org.uk | darksatanic.net | lug.org.uk ===
PGP key: 515C238D from wwwkeys.eu.pgp.net or http://www.carfax.org.uk
--- "I don't like the look of it, I tell you." "Well, stop ---
looking at it, then."
