Is it ever likely to be useful to do "umountall -Z zonename" ?
Perhaps to help release resources from a single zone, rather than having 
to umountall across all zones simultaneously?

[ My thinking behind this is the recent change to lpstat where the -l 
flag suddenly started taking an additional parameter, and that broke all 
sorts of customer scripts which were used to the "lpstat -lp" command. 
I'd like to avoid a future incompatibility, but it depends on the 
expected target audience of this flag... ]

Does this additional flag need to be added to the man page at all? Could 
it simply be a "private" flag? Is the -Z flag ever expected to be run by 
the average sysadmin on the command-line, or would it be confined to the 
zones stop method?

As long as the change to the default behaviour is noted (and frankly I 
would have expected umountall to operate in the current zone only 
anyway), and if the only place it is likely to be used is the zones stop 
method, I imagine the -Z could be an "undocumented" flag (cf. "savecore 
-m", only used in the bootup sequence).

Thanks,
Brian


Rich.Brown at Sun.COM wrote:
> I'm sponsoring this case for Pavel Filipensky to add the '-Z' option to
> umountall(1M).  This case times out on 12/18/2008.
>
> Micro/patch binding is requested for this case.
>
>
> Template Version: @(#)sac_nextcase %I% %G% SMI
> This information is Copyright 2008 Sun Microsystems
> 1. Introduction
>     1.1. Project/Component Working Name:
>        umountall -Z
>     1.2. Name of Document Author/Supplier:
>        Author:  Pavel Filipensky
>     1.3  Date of This Document:
>       11 December, 2008
> 4. Technical Description
>
> This case proposes two changes:
>
> 1) It introduces a new command line option, -Z, to umountall(1M).  When
>    the umountall(1M) command is run in the global zone, this option
>    applies the unmounting action(s) only to the file systems mounted in
>    non-global zones.  The use of -Z option in non-global zones will
>    have no effect.
>
> 2) The default behavior of umountall(1M) is changed to limit the
>    unmounting action(s) to the current zone. 
>
>
> Rationale for limiting the default scope to the current zone:
>
> Currently, running umountall(1M) in the global zone unmounts file
> systems from the global zone and from non-global zones as well.  This
> is causing following bugs:
>
>   6502014 NFS mounts in non-global zones are unmounted if NFS is restarted in 
> the global zone
>   6512906 Autofs mounts in non-global zones are unmounted when autofs is 
> restarted in the global zone
>   6777323 smb mounts in non-global zones are unmounted when smb/client is 
> restarted in the global zone
>
> Limiting the default scope of umountall(1M) to the current zone will
> fix the bugs above.
>
> Rationale for adding the new -Z option:
>
> The -Z option will be used in the stop method of
> svc:/system/zones:default.  This will take care of the case when we try
> to stop zones and some of them fail to shut down.  It is better to try
> to unmount the filesystems mounted in them to free resources on the
> servers.
>
> There are no side effects of using -Z option on other suboptions to
> umountall(1).  Using -Z never changes the behaviour of other
> suboptions, -Z only changes their scope.
>
>
> The webrev for these changes is available here:
>       http://cr.opensolaris.org/~pavelf/6779275
>
>
> Related CR:
>
>   6779275 umountall(1M) -Z  ... limit unmounting action(s) to the non-global 
> zones
>
> EXPORTED INTERFACES
>
>       umountall(1M) option    Stability Level
>
>               -Z              Committed
>     
> DOCUMENTATION IMPACT (See 6780521)
>
>   manpage umountall(1M) changes:
>       1. a new -Z option
>       2. change in the default behavior
>
>
>   Changes are as follows:
>
>   SYNOPSIS
>        mountall [-F FSType] [-l | -r] [file_system_table]
>         
>        umountall [-k] [-s] [-F FSType] [-l | -r] [-n]  [-Z]   +
>         
>        umountall [-k] [-s] [-h host] [-n] [-Z]                +
>   [...]
>        umountall causes all mounted file  systems  in  the  current  +
>        zone except root, /usr, /var, /var/adm, /var/run, /proc, and  +
>        /dev/fd to be unmounted. If the FSType is  specified,  moun-
>        tall  and umountall limit their actions to the FSType speci-
>   [...]
>        -s         Do not perform the umount operation in parallel.
>         
>        -Z         Apply the action(s)  only  to  the  file  systems  +
>                   mounted  in  non-global zones. By default, umoun-  +
>                   tall unmounts only file systems  mounted  in  the  +
>                   current  zone.  Has  no  effect if used in a non-  +
>                   global zone.                                       +
>         
>   FILES
>   [...]   
>
>
> 6. Resources and Schedule
>     6.4. Steering Committee requested information
>       6.4.1. Consolidation C-team Name:
>               ON
>     6.5. ARC review type: FastTrack
>     6.6. ARC Exposure: open
>
>   

-- 
Brian Ruthven                                        Sun Microsystems UK
Solaris Revenue Product Engineering             Tel: +44 (0)1252 422 312
Sparc House, Guillemont Park, Camberley, GU17 9QG


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