I''m curious about this bit of documentation - "By default xend will select a random address[.]" [ http://wiki.xensource.com/xenwiki/XenNetworking ] A couple paragraphs later, this appears - "It''s recommended to use a MAC address inside the range 00:16:3e:xx:xx:xx. This address range is reserved for use by Xen." My user has MACs starting with 1A5DA4, 42A1FD and CE8CF4 so these would appear to be bogus MACs (and potentially evidence of a bad ethernet driver). The "random" bit ... is there some reason the entire MAC address should be selected randomly vs. using the vendor portion and randomly selecting the other half? I tripped over this today while trying to track down problems with multiple bogus MAC addresses on a port (co-existing with VMware MACs) and was informed by the user that they were using Xen. VMware appears to use the IEEE assigned vendor portion and randomly select the other half -- so I don''t understand why Xen should go completely random in all 6 bytes (minus 1 bit, of course) ? ... unless it''s something my user has misconfigured, but I''m coming from the network side of the house and have never actually run Xen on anything. andrew. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
On 21/09/2009 22:09, "Andrew Brennan" <andrew.brennan@drexel.edu> wrote:> I''m curious about this bit of documentation - "By default xend will select > a random address[.]" [ http://wiki.xensource.com/xenwiki/XenNetworking ] > A couple paragraphs later, this appears - "It''s recommended to use a MAC > address inside the range 00:16:3e:xx:xx:xx. This address range is reserved > for use by Xen." My user has MACs starting with 1A5DA4, 42A1FD and CE8CF4 > so these would appear to be bogus MACs (and potentially evidence of a bad > ethernet driver).Our MAC address generator is below, and seems to do the right thing. The user may have specified their own MAC addresses in their VM configuration files (either manually, or perhaps the file could get generated by a vendor ''wizard'' application). -- Keir mac = [ 0x00, 0x16, 0x3e, random.randint(0x00, 0x7f), random.randint(0x00, 0xff), random.randint(0x00, 0xff) ] return '':''.join(map(lambda x: "%02x" % x, mac)) _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel