[OmniOS-discuss] Ang: Continuing zone shutdown issues with r151016

[Bob Friesenhahn]

On Thu, 31 Mar 2016, Jim Klimov wrote:
>
> Forgot to add: the cases similar to what i described can be inspected with fuser (-c, -m IIRC) to see if any processes block the zoneroot filesystems. Also blockage can be due to mounts underneath and other kernel-provided blockers, that userspace fuser won't show.
>
> In particular then look out for nfs+autofs client in a zone (something sol10 documented as a no-no, especiakly to not use nfs from gz of the same server, but which just worked and was cool to e.g. share homedirs or distribs, and so was widely used) - perhaps autofs failed to unmount something from a remote host, then was killed by lz shutdown, and then the remaining sub-fs blocks the zoneroot teardown.

This is not my situation.  None of the zones are currently doing nfs 
client mounts or have any dependence on the root zone other than lofi 
mounts to a zfs filesystem.  However, there is a "Device busy" type 
error.

Some may remember that there are messages on the console which suggest 
a resource contention problem and that I previously captured some 
information and made it available under this ftp URL:

ftp://ftp.simplesystems.org/pub/outgoing/omnios/zoneadmd/

The zoneadmd program issues logs with text like:

"failed to open console master: Device busy"
" WARNING: could not open master side of zone console for pkgbuild to 
release slave handle: Device busy"
"WARNING: console /devices//pseudo/zconsnex at 1/zcons at 1 found, but it 
could not be removed.: I/O error"

It is not clear if this "console master" is continually busy (someting 
forgot/failed to close it) or if it is a transient condition which 
would clear itself and be fine after waiting some tens of milliseconds 
and retrying.  What is clear is that the condition continues after it 
first occurs although other usages of the zone are fine.

Bob
-- 
Bob Friesenhahn
bfriesen at simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/