Logging console output for boss/ops VMs
For boss/ops nodes running as VMs, it would be useful to have a way to capture the "xm console" output for diagnostic purposes. This is of particular interest to Hussam at UK since he has all those geniracks to babysit. He says there is a
xend option to do this with PV domUs, but that it doesn't work for HVM domUs (aka, FreeBSD 10.x VMs). The only way he has found to do it is to set the xm.conf file to say the console is a file. But then you lose interactive console ability.
So I know we can do this by running
capture on the control node, I had to make some changes so that it would deal with the annoying habit of Xen changing the pty device when an HVM reboots, but it seems to be working okay since then. But then there is the issue of interactive access.
capture is usually configured so that it reports a secret to boss and then boss mediates access to the capture process via
console. But there is no obvious "boss" in this situation. However, once upon a time I think we had a version of
console or some other hack that allowed local connection to the capture process without authentication. That would work in this case, but I will have to resurrect that knowledge...