Hi Currently I have 400+ users with quota set to 500MB limit. Currently the file system is using veritas file system. I am planning to migrate all these home directory to a new server with ZFS. How can i migrate the quotas. I can create 400+ file system for each users, but will this affect my system performance during the system boot up? Is this recommanded or any alternate is available for this issue. -- This message posted from opensolaris.org
On Fri, June 18, 2010 08:29, Sendil wrote:> I can create 400+ file system for each users, > but will this affect my system performance during the system boot up? > Is this recommanded or any alternate is available for this issue.You can create a dataset for each user, and then set a per-dataset quota for each one:> quota=size | none > > Limits the amount of space a dataset and its descendents can > consume. This property enforces a hard limit on the amount of > space used. This includes all space consumed by descendents, > including file systems and snapshots. Setting a quota on a > descendent of a dataset that already has a quota does not > override the ancestor''s quota, but rather imposes an additional > limit.Or, on newer revisions of ZFS, you can have one big data set and put all your users in there, and then set per-user quotas:> userquota at user=size | none > > Limits the amount of space consumed by the specified > user. Similar to the refquota property, the userquota space > calculation does not include space that is used by descendent > datasets, such as snapshots and clones. User space consumption > is identified by the userspace at user property.There''s also a "groupquota". See zfs(1M) for details: http://docs.sun.com/app/docs/doc/819-2240/zfs-1m Availability of "userquota" depends on the version of (Open)Solaris that you have; don''t recall when it was introduced. As for which one is better, that depends: per-user adds flexibility, but a bit of overhead. Best to test things out for yourself to see if it works in your environment. You could always split things up into groups of (say) 50. A few jobs ago, I was in an environment where we have a /home/students1/ and /home/students2/, along with a separate faculty/ (using Solaris and UFS). This had more to do with IOps than anything else.
David Magda wrote:> On Fri, June 18, 2010 08:29, Sendil wrote: > >> I can create 400+ file system for each users, >> but will this affect my system performance during the system boot up? >> Is this recommanded or any alternate is available for this issue. > > You can create a dataset for each user, and then set a per-dataset quota > for each one: > >> quota=size | none >>as a side note, you do not need to worry about creating 400 filesystems. A few thousand are no problem. --Arne
On Fri, Jun 18, 2010 at 8:09 AM, David Magda <dmagda at ee.ryerson.ca> wrote:> You could always split things up into groups of (say) 50. A few jobs ago, > I was in an environment where we have a /home/students1/ and > /home/students2/, along with a separate faculty/ (using Solaris and UFS). > This had more to do with IOps than anything else.A decade or so ago when I managed similar environments and had (I think) 6 file systems handling about 5000 students. Each file system had about 1/6 of the students. Challenges I found in this were: - Students needed to work on projects together. The typical way to do this was for them to request a group, then create a group writable directory in one of their home directories. If all students in the group had home directories on the same file system, there was nothing special to consider. If they were on different file systems then at least one would need to have a non-zero quota (that is, not 0 blocks soft, 1 block hard) quota on the file system where the group directory resides. - Despite your best efforts things will get imbalanced. If you are tight on space, this means that you will need to migrate users. This will become apparent only at the times of the semester where even per-user outages are most inconvenient (i.e. at 6 and 13 weeks when big projects tend to be due). Its probably a good idea to consider these types of situations in the transition plan, or at least determine they don''t apply. I was working in a college of engineering where group projects were common and CAD, EDA, and simulation tools could generate big files very quickly. -- Mike Gerdts http://mgerdts.blogspot.com/
P.S. User/group quotas are available in the Solaris 10 release, starting in the Solaris 10 10/09 release: http://docs.sun.com/app/docs/doc/819-5461/gazvb?l=en&a=view Thanks, Cindy On 06/18/10 07:09, David Magda wrote:> On Fri, June 18, 2010 08:29, Sendil wrote: > >> I can create 400+ file system for each users, >> but will this affect my system performance during the system boot up? >> Is this recommanded or any alternate is available for this issue. > > You can create a dataset for each user, and then set a per-dataset quota > for each one: > >> quota=size | none >> >> Limits the amount of space a dataset and its descendents can >> consume. This property enforces a hard limit on the amount of >> space used. This includes all space consumed by descendents, >> including file systems and snapshots. Setting a quota on a >> descendent of a dataset that already has a quota does not >> override the ancestor''s quota, but rather imposes an additional >> limit. > > Or, on newer revisions of ZFS, you can have one big data set and put all > your users in there, and then set per-user quotas: > >> userquota at user=size | none >> >> Limits the amount of space consumed by the specified >> user. Similar to the refquota property, the userquota space >> calculation does not include space that is used by descendent >> datasets, such as snapshots and clones. User space consumption >> is identified by the userspace at user property. > > There''s also a "groupquota". See zfs(1M) for details: > > http://docs.sun.com/app/docs/doc/819-2240/zfs-1m > > Availability of "userquota" depends on the version of (Open)Solaris that > you have; don''t recall when it was introduced. > > As for which one is better, that depends: per-user adds flexibility, but a > bit of overhead. Best to test things out for yourself to see if it works > in your environment. > > You could always split things up into groups of (say) 50. A few jobs ago, > I was in an environment where we have a /home/students1/ and > /home/students2/, along with a separate faculty/ (using Solaris and UFS). > This had more to do with IOps than anything else. > > _______________________________________________ > zfs-discuss mailing list > zfs-discuss at opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
----- Original Message -----> Hi > Currently I have 400+ users with quota set to 500MB limit. Currently > the file system is using veritas file system. > > I am planning to migrate all these home directory to a new server with > ZFS. How can i migrate the quotas. > > I can create 400+ file system for each users, > but will this affect my system performance during the system boot up? > Is this recommanded or any alternate is available for this issue.There''s a lot of info in a thread I started quite recently "One dataset per user?". Take a look in there. Vennlige hilsener / Best regards roy -- Roy Sigurd Karlsbakk (+47) 97542685 roy at karlsbakk.net http://blogg.karlsbakk.net/ -- I all pedagogikk er det essensielt at pensum presenteres intelligibelt. Det er et element?rt imperativ for alle pedagoger ? unng? eksessiv anvendelse av idiomer med fremmed opprinnelse. I de fleste tilfeller eksisterer adekvate og relevante synonymer p? norsk.