How can I set up a ZVOL that''s accessible by non-root users, too? The intent is to use sparse ZVOLs as raw disks in virtualization (reducing overhead compared to file-based virtual volumes). Thanks, -mg This message posted from opensolaris.org
Could someone kindly provide some details on using a zvol in sparse-mode? Wouldn''t the COW nature of zfs (assuming COW still applies on ZVOLS) quickly erode the sparse nature of the zvol? Would sparse data-presentation only work by delegating a part of a zpool to a zone, but that''s at the file-level, not raw? Thanks -- mikee ----- Original Message ----- From: zfs-discuss-bounces at opensolaris.org <zfs-discuss-bounces at opensolaris.org> To: zfs-discuss at opensolaris.org <zfs-discuss at opensolaris.org> Sent: Sat Apr 12 10:02:18 2008 Subject: [zfs-discuss] ZVOL access permissions? How can I set up a ZVOL that''s accessible by non-root users, too? The intent is to use sparse ZVOLs as raw disks in virtualization (reducing overhead compared to file-based virtual volumes). Thanks, -mg This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss at opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Hello Mike,
Saturday, April 12, 2008, 4:17:30 PM, you wrote:
EM> Could someone kindly provide some details on using a zvol in sparse-mode?
EM> Wouldn''t the COW nature of zfs (assuming COW still applies on
EM> ZVOLS) quickly erode the sparse nature of the zvol?
COW does apply to zvols. If you once used entire zvol logical space
physical utilization will match logical and you won''t be able to
re-gain it (unless you re-create zvol). So yes, it is not as good as
with file systems, but it can''t be any better and is no worse than
other thin provisioning offered by arrays these days.
If you have well controlled environment it should work good enough.
EM> Would sparse data-presentation only work by delegating a part of
EM> a zpool to a zone, but that''s at the file-level, not raw?
It is not required - you create X size zvol which is sparse and it
will allocate physical storage only when some data is written. Zones
have nothing to do here.
--
Best regards,
Robert Milkowski mailto:milek at task.gda.pl
http://milek.blogspot.com
Hello Mario,
Saturday, April 12, 2008, 3:02:18 PM, you wrote:
MG> How can I set up a ZVOL that''s accessible by non-root users,
too?
MG> The intent is to use sparse ZVOLs as raw disks in virtualization
MG> (reducing overhead compared to file-based virtual volumes).
change zvol permissions to whatever you want?
--
Best regards,
Robert Milkowski mailto:milek at task.gda.pl
http://milek.blogspot.com
> MG> How can I set up a ZVOL that''s accessible by non-root users, too? > MG> The intent is to use sparse ZVOLs as raw disks in virtualization > MG> (reducing overhead compared to file-based virtual volumes). > > change zvol permissions to whatever you want?The nodes in /dev/zvol are all 777 from the start. The ones in /devices, to which the /dev ones link, are just 400. Changing them only lasts until you reboot. -mg
Mario Goebbels (Webmail) wrote:> >> MG> How can I set up a ZVOL that''s accessible by non-root users, too? >> MG> The intent is to use sparse ZVOLs as raw disks in virtualization >> MG> (reducing overhead compared to file-based virtual volumes). >> >> change zvol permissions to whatever you want? > > The nodes in /dev/zvol are all 777 from the start. The ones in /devices, to > which the /dev ones link, are just 400.That is because the /dev/zvol files are actually symlinks and on Solaris symlinks don''t have their own permissions so you see lrwxrwxrwx instead. -- Darren J Moffat