VM trying to add serial console to examine boot process.

kevdog

So long story short is that I was working with an arch-linux vm within xcp-ng and trying to debug why ZFSBootMenu wont work to boot my VM with my / partition on zfs. If interested the details or documented here: https://www.reddit.com/r/zfs/comments/1p1veqf/damn_struggling_to_get_zfsbootmenu_to_work/

Anyway one of the proposed methods of trying to debug the problem of why the ZFSBootMenu EFI wont boot the kernel was to try to add a serial port to the VM to gather output. Adding a serial port to a VM was something new to me and I actually tried two methods:

SSH'd into the DOM image, I tried running the commands:

# xl vm-list  ---- This got me the VM id #
# xl console -t serial <ID #>

This didn't seem to produce any output so I went another method was to add a serial port that dumped it's output to a tcp port:

# xe vm-param-add uuid=<uuid> param-name=platform hvm_serial=tcp::7001,server,nodelay

I then from a remote host tried to see to listed on tcp port 7001:

#nc -v <ip_address> 7001

and yes that didn't work either in terms of producing any output.

I am going about this the correct way in terms of trying to attach a serial port? For the record if anyone has worked with ZFSBootMenu my parameters I'm adjusting here are the following:

# zfs set org.zfsbootmenu:commandline="spl.spl_hostid=$(hostid) loglevel=7 rw console=ttyS0" tank/sys/arch/ROOT/default