Re: Odd uuid-ossp behavior on smew and shearwater

On Thu, May 29, 2014 at 4:06 PM, Andrew Dunstan <andrew(at)dunslane(dot)net> wrote:
> On 05/29/2014 02:38 PM, Tom Lane wrote:
>> Josh Kupershmidt <schmiddy(at)gmail(dot)com> writes:
>> Interesting. Looks like you have access only to virtual network
>> interfaces, and they report all-zero MAC addresses, which the UUID library
>> is smart enough to ignore. If smew is also in a virtual environment
>> then that's probably the explanation. (There are some other buildfarm
>> critters that are reporting MAC addresses with the local-admin bit set,
>> which I suspect also means they've got virtual network interfaces, but
>> with a different treatment of the what-to-report problem.)

> Almost all my critters run in VMs (all but jacana and bowerbird).

They're not running on OpenVZ, are they? `ifconfig` on shearwater says:

venet0 Link encap:UNSPEC HWaddr
00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
inet addr:127.0.0.2 P-t-P:127.0.0.2 Bcast:0.0.0.0
Mask:255.255.255.255
UP BROADCAST POINTOPOINT RUNNING NOARP MTU:1500 Metric:1
RX packets:1409294 errors:0 dropped:0 overruns:0 frame:0
TX packets:1488401 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:751149524 (716.3 MiB) TX bytes:740573200 (706.2 MiB)

venet0:0 Link encap:UNSPEC HWaddr
00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
inet addr:198.204.250.34 P-t-P:198.204.250.34
Bcast:0.0.0.0 Mask:255.255.255.255
UP BROADCAST POINTOPOINT RUNNING NOARP MTU:1500 Metric:1

and it seems this all-zeros MAC address is a common
(mis-?)configuration on OpenVZ:

https://github.com/robertdavidgraham/masscan/issues/43
http://stackoverflow.com/questions/5838225/how-do-i-get-a-default-gridgain-node-in-openvz-discover-other-nodes-on-the-same
http://forum.openvz.org/index.php?t=msg&goto=8117