Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem
My understanding was that this was perfectly acceptable in a GPFS system. i.e. mounting parts of file-systems in others. It has been suggested to us as a way of using different vendor GPFS systems (e.g. an ESS with someone elses) as a way of working round the licensing rules about ESS and anything else, but still giving a single user “name space”. We didn’t go that route, and of course I might have misunderstood what was being suggested. Simon From: on behalf of "marc.cau...@psi.ch" Reply to: "gpfsug-discuss@spectrumscale.org" Date: Thursday, 19 November 2020 at 18:13 To: "gpfsug-discuss@spectrumscale.org" Subject: Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem Hi all, thanks a lot for your comments. Agreed, I better avoid it for now. I was concerned about how GPFS would behave in such case. For production I will take the safe route, but, just out of curiosity, I'll give it a try on a couple of test filesystems. Thanks a lot for your help, it was very helpful, Marc _ Paul Scherrer Institut High Performance Computing & Emerging Technologies Marc Caubet Serrabou Building/Room: OHSA/014 Forschungsstrasse, 111 5232 Villigen PSI Switzerland Telephone: +41 56 310 46 67 E-Mail: marc.cau...@psi.ch From: gpfsug-discuss-boun...@spectrumscale.org on behalf of Skylar Thompson Sent: Thursday, November 19, 2020 6:38:07 PM To: gpfsug-discuss@spectrumscale.org Subject: Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem Agreed, not sure how the GPFS tools would react. An alternative to symlinks would be bind mounts, if for some reason a tool doesn't behave properly with a symlink in the path. On Thu, Nov 19, 2020 at 06:34:05PM +0100, Jan-Frode Myklebust wrote: > I would not mount a GPFS filesystem within a GPFS filesystem. Technically > it should work, but I???d expect it to cause surprises if ever the lower > filesystem experienced problems. Alone, a filesystem might recover > automatically by remounting. But if there???s another filesystem mounted > within, I expect it will be a problem.. > > Much better to use symlinks. > > > > -jf > > tor. 19. nov. 2020 kl. 18:01 skrev Caubet Serrabou Marc (PSI) < > marc.cau...@psi.ch>: > > > Hi Simon, > > > > > > that's a very good point, thanks a lot :) I have it remotely mounted on a > > client cluster, so I will consider priorities when mounting the filesystems > > with remote cluster mount. That's very useful. > > > > Also, as far as I saw, same approach can be also applied to local mounts > > (via mmchfs) during daemon startup with the same option --mount-priority. > > > > > > Thanks a lot for the hints, these are very useful. I'll test that. > > > > > > Cheers, > > > > Marc > > _ > > Paul Scherrer Institut > > High Performance Computing & Emerging Technologies > > Marc Caubet Serrabou > > Building/Room: OHSA/014 > > Forschungsstrasse, 111 > > 5232 Villigen PSI > > Switzerland > > > > Telephone: +41 56 310 46 67 > > E-Mail: marc.cau...@psi.ch > > -- > > *From:* gpfsug-discuss-boun...@spectrumscale.org < > > gpfsug-discuss-boun...@spectrumscale.org> on behalf of Simon Thompson < > > s.j.thomp...@bham.ac.uk> > > *Sent:* Thursday, November 19, 2020 5:42:07 PM > > *To:* gpfsug main discussion list > > *Subject:* Re: [gpfsug-discuss] Mounting filesystem on top of an existing > > filesystem > > > > > > If it is a remote cluster mount from your clients (hopefully!), you might > > want to look at priority to order mounting of the file-systems. I don???t > > know what would happen if the overmounted file-system went away, you would > > likely want to test. > > > > > > > > Simon > > > > > > > > *From: * on behalf of " > > marc.cau...@psi.ch" > > *Reply to: *"gpfsug-discuss@spectrumscale.org" < > > gpfsug-discuss@spectrumscale.org> > > *Date: *Thursday, 19 November 2020 at 15:39 > > *To: *"gpfsug-discuss@spectrumscale.org" > > > > *Subject: *[gpfsug-discuss] Mounting filesystem on top of an existing > > filesystem > > > > > > > > Hi, > > > > > > > > I have a filesystem holding many projects (i.e., mounted under /projects), > > each project is managed with filesets. > > > > I have a new big project which should be placed on a separate filesystem > > (blocksize, replication policy, etc. will be different, and subprojects of > > it will be managed with filesets). Ideally, this filesystem should be > > mounted in /projects/newproject. > > > > > > > > Technically, mounting a filesystem on top of an existing filesystem should > > be possible, but, is this discouraged for any reason? How GPFS would behave > > with that and is there a technical reason for avoiding this setup? > > > > Another alternative would be independent mount point + symlink, but I > > really would prefer to avoid symlinks. > > > > > > > > Thanks a lot, > > > > Marc > >
Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem
Just the risk your parent system dies which will block your access to the child file system mounted on a mount point within. If that is not bothering , go ahead mount stacks . As for the symling though : it is also gone if the parent dies :-). Mit freundlichen Grüßen / Kind regards Dr. Uwe Falke IT Specialist Hybrid Cloud Infrastructure / Technology Consulting & Implementation Services +49 175 575 2877 Mobile Rathausstr. 7, 09111 Chemnitz, Germany uwefa...@de.ibm.com IBM Services IBM Data Privacy Statement IBM Deutschland Business & Technology Services GmbH Geschäftsführung: Sven Schooss, Stefan Hierl Sitz der Gesellschaft: Ehningen Registergericht: Amtsgericht Stuttgart, HRB 17122 From: KG To: gpfsug main discussion list Date: 19/11/2020 17:41 Subject:[EXTERNAL] Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem Sent by:gpfsug-discuss-boun...@spectrumscale.org You can also set mount priority on filesystems so that gpfs can try to mount them in order...parent first On Thu, Nov 19, 2020, 21:19 Jonathan Buzzard < jonathan.buzz...@strath.ac.uk> wrote: On 19/11/2020 15:34, Caubet Serrabou Marc (PSI) wrote: > Hi, > > > I have a filesystem holding many projects (i.e., mounted under > /projects), each project is managed with filesets. > > I have a new big project which should be placed on a separate filesystem > (blocksize, replication policy, etc. will be different, and subprojects > of it will be managed with filesets). Ideally, this filesystem should be > mounted in /projects/newproject. > > > Technically, mounting a filesystem on top of an existing filesystem > should be possible, but, is this discouraged for any reason? How GPFS > would behave with that and is there a technical reason for avoiding this > setup? > > Another alternative would be independent mount point + symlink, but I > really would prefer to avoid symlinks. This has all the hallmarks of either a Windows admin or a newbie Linux/Unix admin :-) Simply put /projects is mounted on top of whatever file system is providing the root file system in the first place LOL. Linux/Unix and/or GPFS does not give a monkeys about mounting another file system *ANYWHERE* in it period because there is no other way of doing it. JAB. -- Jonathan A. Buzzard Tel: +44141-5483420 HPC System Administrator, ARCHIE-WeSt. University of Strathclyde, John Anderson Building, Glasgow. G4 0NG ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem
> On Nov 19, 2020, at 10:49 AM, Jonathan Buzzard > wrote: > > On 19/11/2020 15:34, Caubet Serrabou Marc (PSI) wrote: >> Hi, >> I have a filesystem holding many projects (i.e., mounted under /projects), >> each project is managed with filesets. >> I have a new big project which should be placed on a separate filesystem >> (blocksize, replication policy, etc. will be different, and subprojects of >> it will be managed with filesets). Ideally, this filesystem should be >> mounted in /projects/newproject. >> Technically, mounting a filesystem on top of an existing filesystem should >> be possible, but, is this discouraged for any reason? How GPFS would behave >> with that and is there a technical reason for avoiding this setup? >> Another alternative would be independent mount point + symlink, but I really >> would prefer to avoid symlinks. > > This has all the hallmarks of either a Windows admin or a newbie Linux/Unix > admin :-) > > Simply put /projects is mounted on top of whatever file system is providing > the root file system in the first place LOL. > > Linux/Unix and/or GPFS does not give a monkeys about mounting another file > system *ANYWHERE* in it period because there is no other way of doing it. Some others have said, but I disagree. It wasn’t that long ago that GPFS acted really screwy with systemd because it did something in a way other than Linux expected. As it is now, their devices are not /dev/whatever or server:/wherever like just about every other filesystem type. Not unreasonable to believe it would “act funny” compared to other FS. I like GPFS a lot, but this is not one of my favorite characteristics of it. -- #BlackLivesMatter || \\UTGERS, |---*O*--- ||_// the State | Ryan Novosielski - novos...@rutgers.edu || \\ University | Sr. Technologist - 973/972.0922 (2x0922) ~*~ RBHS Campus || \\of NJ | Office of Advanced Research Computing - MSB C630, Newark `' ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem
On 19/11/2020 18:13, Caubet Serrabou Marc (PSI) wrote: Hi all, thanks a lot for your comments. Agreed, I better avoid it for now. I was concerned about how GPFS would behave in such case. For production I will take the safe route, but, just out of curiosity, I'll give it a try on a couple of test filesystems. Don't use symlinks there is a range of applications that will break and you will confuse the hell out of your users as the fact you are not under /projects/new but /random/new is not hidden. Besides which if the symlink goes away because /projects goes away then it is all a bust anyway. If you are worried about /projects going away then the best plan is to mount the GPFS file systems somewhere else and then bind mount the directories into /projects on all the machines where they are mounted. GPFS is quite happy with this. We bind mount /gpfs/users into /users and /gpfs/software into /opt/software by default. In the past I have bind mounted random paths for every user (hundred plus) into /home JAB. -- Jonathan A. Buzzard Tel: +44141-5483420 HPC System Administrator, ARCHIE-WeSt. University of Strathclyde, John Anderson Building, Glasgow. G4 0NG ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem
Hi all, thanks a lot for your comments. Agreed, I better avoid it for now. I was concerned about how GPFS would behave in such case. For production I will take the safe route, but, just out of curiosity, I'll give it a try on a couple of test filesystems. Thanks a lot for your help, it was very helpful, Marc _ Paul Scherrer Institut High Performance Computing & Emerging Technologies Marc Caubet Serrabou Building/Room: OHSA/014 Forschungsstrasse, 111 5232 Villigen PSI Switzerland Telephone: +41 56 310 46 67 E-Mail: marc.cau...@psi.ch From: gpfsug-discuss-boun...@spectrumscale.org on behalf of Skylar Thompson Sent: Thursday, November 19, 2020 6:38:07 PM To: gpfsug-discuss@spectrumscale.org Subject: Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem Agreed, not sure how the GPFS tools would react. An alternative to symlinks would be bind mounts, if for some reason a tool doesn't behave properly with a symlink in the path. On Thu, Nov 19, 2020 at 06:34:05PM +0100, Jan-Frode Myklebust wrote: > I would not mount a GPFS filesystem within a GPFS filesystem. Technically > it should work, but I???d expect it to cause surprises if ever the lower > filesystem experienced problems. Alone, a filesystem might recover > automatically by remounting. But if there???s another filesystem mounted > within, I expect it will be a problem.. > > Much better to use symlinks. > > > > -jf > > tor. 19. nov. 2020 kl. 18:01 skrev Caubet Serrabou Marc (PSI) < > marc.cau...@psi.ch>: > > > Hi Simon, > > > > > > that's a very good point, thanks a lot :) I have it remotely mounted on a > > client cluster, so I will consider priorities when mounting the filesystems > > with remote cluster mount. That's very useful. > > > > Also, as far as I saw, same approach can be also applied to local mounts > > (via mmchfs) during daemon startup with the same option --mount-priority. > > > > > > Thanks a lot for the hints, these are very useful. I'll test that. > > > > > > Cheers, > > > > Marc > > _ > > Paul Scherrer Institut > > High Performance Computing & Emerging Technologies > > Marc Caubet Serrabou > > Building/Room: OHSA/014 > > Forschungsstrasse, 111 > > 5232 Villigen PSI > > Switzerland > > > > Telephone: +41 56 310 46 67 > > E-Mail: marc.cau...@psi.ch > > -- > > *From:* gpfsug-discuss-boun...@spectrumscale.org < > > gpfsug-discuss-boun...@spectrumscale.org> on behalf of Simon Thompson < > > s.j.thomp...@bham.ac.uk> > > *Sent:* Thursday, November 19, 2020 5:42:07 PM > > *To:* gpfsug main discussion list > > *Subject:* Re: [gpfsug-discuss] Mounting filesystem on top of an existing > > filesystem > > > > > > If it is a remote cluster mount from your clients (hopefully!), you might > > want to look at priority to order mounting of the file-systems. I don???t > > know what would happen if the overmounted file-system went away, you would > > likely want to test. > > > > > > > > Simon > > > > > > > > *From: * on behalf of " > > marc.cau...@psi.ch" > > *Reply to: *"gpfsug-discuss@spectrumscale.org" < > > gpfsug-discuss@spectrumscale.org> > > *Date: *Thursday, 19 November 2020 at 15:39 > > *To: *"gpfsug-discuss@spectrumscale.org" > > > > *Subject: *[gpfsug-discuss] Mounting filesystem on top of an existing > > filesystem > > > > > > > > Hi, > > > > > > > > I have a filesystem holding many projects (i.e., mounted under /projects), > > each project is managed with filesets. > > > > I have a new big project which should be placed on a separate filesystem > > (blocksize, replication policy, etc. will be different, and subprojects of > > it will be managed with filesets). Ideally, this filesystem should be > > mounted in /projects/newproject. > > > > > > > > Technically, mounting a filesystem on top of an existing filesystem should > > be possible, but, is this discouraged for any reason? How GPFS would behave > > with that and is there a technical reason for avoiding this setup? > > > > Another alternative would be independent mount point + symlink, but I > > really would prefer to avoid symlinks. > > > > > > > > Thanks a lot, > > > > Marc > > > > _ > > Paul Scherrer Institut > > High Performance Computing & Emerging Technologies > > Marc Caubet Serrabou > > Building/Room: OHSA/014 > > > > Forschungsstrasse, 111 > > > > 5232 Villigen PSI > > Switzerland > > > > Telephone: +41 56 310 46 67 > > E-Mail: marc.cau...@psi.ch > > ___ > > gpfsug-discuss mailing list > > gpfsug-discuss at spectrumscale.org > > http://gpfsug.org/mailman/listinfo/gpfsug-discuss > > > ___ > gpfsug-discuss mailing list > gpfsug-discuss at spectrumscale.org > http://gpfsug.org/mailman/listinfo/gpfsug-discuss -- -- Skylar Thompson
Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem
On 19/11/2020 16:40, KG wrote: You can also set mount priority on filesystems so that gpfs can try to mount them in order...parent first One of the things that systemd brings to the table https://github.com/systemd/systemd/commit/3519d230c8bafe834b2dac26ace49fcfba139823 JAB. -- Jonathan A. Buzzard Tel: +44141-5483420 HPC System Administrator, ARCHIE-WeSt. University of Strathclyde, John Anderson Building, Glasgow. G4 0NG ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem
On 19/11/2020 17:34, Jan-Frode Myklebust wrote: I would not mount a GPFS filesystem within a GPFS filesystem. Technically it should work, but I’d expect it to cause surprises if ever the lower filesystem experienced problems. Alone, a filesystem might recover automatically by remounting. But if there’s another filesystem mounted within, I expect it will be a problem.. Much better to use symlinks. Think about that for a minute... I guess if you are worried about /projects going away (which would suggest something really bad has happened anyway) would be to mount the GPFS file system that is currently holding /projects somewhere else and then bind mount everything into /projects At this point I would note that bind mounts are much better than symlinks which suck for this sort of application. JAB. -- Jonathan A. Buzzard Tel: +44141-5483420 HPC System Administrator, ARCHIE-WeSt. University of Strathclyde, John Anderson Building, Glasgow. G4 0NG ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem
Agreed, not sure how the GPFS tools would react. An alternative to symlinks would be bind mounts, if for some reason a tool doesn't behave properly with a symlink in the path. On Thu, Nov 19, 2020 at 06:34:05PM +0100, Jan-Frode Myklebust wrote: > I would not mount a GPFS filesystem within a GPFS filesystem. Technically > it should work, but I???d expect it to cause surprises if ever the lower > filesystem experienced problems. Alone, a filesystem might recover > automatically by remounting. But if there???s another filesystem mounted > within, I expect it will be a problem.. > > Much better to use symlinks. > > > > -jf > > tor. 19. nov. 2020 kl. 18:01 skrev Caubet Serrabou Marc (PSI) < > marc.cau...@psi.ch>: > > > Hi Simon, > > > > > > that's a very good point, thanks a lot :) I have it remotely mounted on a > > client cluster, so I will consider priorities when mounting the filesystems > > with remote cluster mount. That's very useful. > > > > Also, as far as I saw, same approach can be also applied to local mounts > > (via mmchfs) during daemon startup with the same option --mount-priority. > > > > > > Thanks a lot for the hints, these are very useful. I'll test that. > > > > > > Cheers, > > > > Marc > > _ > > Paul Scherrer Institut > > High Performance Computing & Emerging Technologies > > Marc Caubet Serrabou > > Building/Room: OHSA/014 > > Forschungsstrasse, 111 > > 5232 Villigen PSI > > Switzerland > > > > Telephone: +41 56 310 46 67 > > E-Mail: marc.cau...@psi.ch > > -- > > *From:* gpfsug-discuss-boun...@spectrumscale.org < > > gpfsug-discuss-boun...@spectrumscale.org> on behalf of Simon Thompson < > > s.j.thomp...@bham.ac.uk> > > *Sent:* Thursday, November 19, 2020 5:42:07 PM > > *To:* gpfsug main discussion list > > *Subject:* Re: [gpfsug-discuss] Mounting filesystem on top of an existing > > filesystem > > > > > > If it is a remote cluster mount from your clients (hopefully!), you might > > want to look at priority to order mounting of the file-systems. I don???t > > know what would happen if the overmounted file-system went away, you would > > likely want to test. > > > > > > > > Simon > > > > > > > > *From: * on behalf of " > > marc.cau...@psi.ch" > > *Reply to: *"gpfsug-discuss@spectrumscale.org" < > > gpfsug-discuss@spectrumscale.org> > > *Date: *Thursday, 19 November 2020 at 15:39 > > *To: *"gpfsug-discuss@spectrumscale.org" > > > > *Subject: *[gpfsug-discuss] Mounting filesystem on top of an existing > > filesystem > > > > > > > > Hi, > > > > > > > > I have a filesystem holding many projects (i.e., mounted under /projects), > > each project is managed with filesets. > > > > I have a new big project which should be placed on a separate filesystem > > (blocksize, replication policy, etc. will be different, and subprojects of > > it will be managed with filesets). Ideally, this filesystem should be > > mounted in /projects/newproject. > > > > > > > > Technically, mounting a filesystem on top of an existing filesystem should > > be possible, but, is this discouraged for any reason? How GPFS would behave > > with that and is there a technical reason for avoiding this setup? > > > > Another alternative would be independent mount point + symlink, but I > > really would prefer to avoid symlinks. > > > > > > > > Thanks a lot, > > > > Marc > > > > _ > > Paul Scherrer Institut > > High Performance Computing & Emerging Technologies > > Marc Caubet Serrabou > > Building/Room: OHSA/014 > > > > Forschungsstrasse, 111 > > > > 5232 Villigen PSI > > Switzerland > > > > Telephone: +41 56 310 46 67 > > E-Mail: marc.cau...@psi.ch > > ___ > > gpfsug-discuss mailing list > > gpfsug-discuss at spectrumscale.org > > http://gpfsug.org/mailman/listinfo/gpfsug-discuss > > > ___ > gpfsug-discuss mailing list > gpfsug-discuss at spectrumscale.org > http://gpfsug.org/mailman/listinfo/gpfsug-discuss -- -- Skylar Thompson (skyl...@u.washington.edu) -- Genome Sciences Department (UW Medicine), System Administrator -- Foege Building S046, (206)-685-7354 -- Pronouns: He/Him/His ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem
I would not mount a GPFS filesystem within a GPFS filesystem. Technically it should work, but I’d expect it to cause surprises if ever the lower filesystem experienced problems. Alone, a filesystem might recover automatically by remounting. But if there’s another filesystem mounted within, I expect it will be a problem.. Much better to use symlinks. -jf tor. 19. nov. 2020 kl. 18:01 skrev Caubet Serrabou Marc (PSI) < marc.cau...@psi.ch>: > Hi Simon, > > > that's a very good point, thanks a lot :) I have it remotely mounted on a > client cluster, so I will consider priorities when mounting the filesystems > with remote cluster mount. That's very useful. > > Also, as far as I saw, same approach can be also applied to local mounts > (via mmchfs) during daemon startup with the same option --mount-priority. > > > Thanks a lot for the hints, these are very useful. I'll test that. > > > Cheers, > > Marc > _ > Paul Scherrer Institut > High Performance Computing & Emerging Technologies > Marc Caubet Serrabou > Building/Room: OHSA/014 > Forschungsstrasse, 111 > 5232 Villigen PSI > Switzerland > > Telephone: +41 56 310 46 67 > E-Mail: marc.cau...@psi.ch > -- > *From:* gpfsug-discuss-boun...@spectrumscale.org < > gpfsug-discuss-boun...@spectrumscale.org> on behalf of Simon Thompson < > s.j.thomp...@bham.ac.uk> > *Sent:* Thursday, November 19, 2020 5:42:07 PM > *To:* gpfsug main discussion list > *Subject:* Re: [gpfsug-discuss] Mounting filesystem on top of an existing > filesystem > > > If it is a remote cluster mount from your clients (hopefully!), you might > want to look at priority to order mounting of the file-systems. I don’t > know what would happen if the overmounted file-system went away, you would > likely want to test. > > > > Simon > > > > *From: * on behalf of " > marc.cau...@psi.ch" > *Reply to: *"gpfsug-discuss@spectrumscale.org" < > gpfsug-discuss@spectrumscale.org> > *Date: *Thursday, 19 November 2020 at 15:39 > *To: *"gpfsug-discuss@spectrumscale.org" > > *Subject: *[gpfsug-discuss] Mounting filesystem on top of an existing > filesystem > > > > Hi, > > > > I have a filesystem holding many projects (i.e., mounted under /projects), > each project is managed with filesets. > > I have a new big project which should be placed on a separate filesystem > (blocksize, replication policy, etc. will be different, and subprojects of > it will be managed with filesets). Ideally, this filesystem should be > mounted in /projects/newproject. > > > > Technically, mounting a filesystem on top of an existing filesystem should > be possible, but, is this discouraged for any reason? How GPFS would behave > with that and is there a technical reason for avoiding this setup? > > Another alternative would be independent mount point + symlink, but I > really would prefer to avoid symlinks. > > > > Thanks a lot, > > Marc > > _ > Paul Scherrer Institut > High Performance Computing & Emerging Technologies > Marc Caubet Serrabou > Building/Room: OHSA/014 > > Forschungsstrasse, 111 > > 5232 Villigen PSI > Switzerland > > Telephone: +41 56 310 46 67 > E-Mail: marc.cau...@psi.ch > ___ > gpfsug-discuss mailing list > gpfsug-discuss at spectrumscale.org > http://gpfsug.org/mailman/listinfo/gpfsug-discuss > ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem
Hi Simon, that's a very good point, thanks a lot :) I have it remotely mounted on a client cluster, so I will consider priorities when mounting the filesystems with remote cluster mount. That's very useful. Also, as far as I saw, same approach can be also applied to local mounts (via mmchfs) during daemon startup with the same option --mount-priority. Thanks a lot for the hints, these are very useful. I'll test that. Cheers, Marc _ Paul Scherrer Institut High Performance Computing & Emerging Technologies Marc Caubet Serrabou Building/Room: OHSA/014 Forschungsstrasse, 111 5232 Villigen PSI Switzerland Telephone: +41 56 310 46 67 E-Mail: marc.cau...@psi.ch From: gpfsug-discuss-boun...@spectrumscale.org on behalf of Simon Thompson Sent: Thursday, November 19, 2020 5:42:07 PM To: gpfsug main discussion list Subject: Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem If it is a remote cluster mount from your clients (hopefully!), you might want to look at priority to order mounting of the file-systems. I don’t know what would happen if the overmounted file-system went away, you would likely want to test. Simon From: on behalf of "marc.cau...@psi.ch" Reply to: "gpfsug-discuss@spectrumscale.org" Date: Thursday, 19 November 2020 at 15:39 To: "gpfsug-discuss@spectrumscale.org" Subject: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem Hi, I have a filesystem holding many projects (i.e., mounted under /projects), each project is managed with filesets. I have a new big project which should be placed on a separate filesystem (blocksize, replication policy, etc. will be different, and subprojects of it will be managed with filesets). Ideally, this filesystem should be mounted in /projects/newproject. Technically, mounting a filesystem on top of an existing filesystem should be possible, but, is this discouraged for any reason? How GPFS would behave with that and is there a technical reason for avoiding this setup? Another alternative would be independent mount point + symlink, but I really would prefer to avoid symlinks. Thanks a lot, Marc _ Paul Scherrer Institut High Performance Computing & Emerging Technologies Marc Caubet Serrabou Building/Room: OHSA/014 Forschungsstrasse, 111 5232 Villigen PSI Switzerland Telephone: +41 56 310 46 67 E-Mail: marc.cau...@psi.ch ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem
Hi Jonathan, thanks for sharing your opinions. In the sentence "Technically, mounting a filesystem on top of an existing filesystem should be possible" , I guess I was referring to that... I was concerned about other technical reasons, such like how would this would affect GPFS policies, or how to properly proceed with proper mounting, or any other technical reasons to consider. For the GPFS policies, I usually applied some of the existing GPFS policies based on directories, but after checking I realized that one can manage via device (never used policies in that way, at least for the simple but necessary use cases I have on the existing filesystems). Thanks a lot, Marc _ Paul Scherrer Institut High Performance Computing & Emerging Technologies Marc Caubet Serrabou Building/Room: OHSA/014 Forschungsstrasse, 111 5232 Villigen PSI Switzerland Telephone: +41 56 310 46 67 E-Mail: marc.cau...@psi.ch From: gpfsug-discuss-boun...@spectrumscale.org on behalf of Jonathan Buzzard Sent: Thursday, November 19, 2020 4:49:30 PM To: gpfsug-discuss@spectrumscale.org Subject: Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem On 19/11/2020 15:34, Caubet Serrabou Marc (PSI) wrote: > Hi, > > > I have a filesystem holding many projects (i.e., mounted under > /projects), each project is managed with filesets. > > I have a new big project which should be placed on a separate filesystem > (blocksize, replication policy, etc. will be different, and subprojects > of it will be managed with filesets). Ideally, this filesystem should be > mounted in /projects/newproject. > > > Technically, mounting a filesystem on top of an existing filesystem > should be possible, but, is this discouraged for any reason? How GPFS > would behave with that and is there a technical reason for avoiding this > setup? > > Another alternative would be independent mount point + symlink, but I > really would prefer to avoid symlinks. This has all the hallmarks of either a Windows admin or a newbie Linux/Unix admin :-) Simply put /projects is mounted on top of whatever file system is providing the root file system in the first place LOL. Linux/Unix and/or GPFS does not give a monkeys about mounting another file system *ANYWHERE* in it period because there is no other way of doing it. JAB. -- Jonathan A. Buzzard Tel: +44141-5483420 HPC System Administrator, ARCHIE-WeSt. University of Strathclyde, John Anderson Building, Glasgow. G4 0NG ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem
If it is a remote cluster mount from your clients (hopefully!), you might want to look at priority to order mounting of the file-systems. I don’t know what would happen if the overmounted file-system went away, you would likely want to test. Simon From: on behalf of "marc.cau...@psi.ch" Reply to: "gpfsug-discuss@spectrumscale.org" Date: Thursday, 19 November 2020 at 15:39 To: "gpfsug-discuss@spectrumscale.org" Subject: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem Hi, I have a filesystem holding many projects (i.e., mounted under /projects), each project is managed with filesets. I have a new big project which should be placed on a separate filesystem (blocksize, replication policy, etc. will be different, and subprojects of it will be managed with filesets). Ideally, this filesystem should be mounted in /projects/newproject. Technically, mounting a filesystem on top of an existing filesystem should be possible, but, is this discouraged for any reason? How GPFS would behave with that and is there a technical reason for avoiding this setup? Another alternative would be independent mount point + symlink, but I really would prefer to avoid symlinks. Thanks a lot, Marc _ Paul Scherrer Institut High Performance Computing & Emerging Technologies Marc Caubet Serrabou Building/Room: OHSA/014 Forschungsstrasse, 111 5232 Villigen PSI Switzerland Telephone: +41 56 310 46 67 E-Mail: marc.cau...@psi.ch ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem
You can also set mount priority on filesystems so that gpfs can try to mount them in order...parent first On Thu, Nov 19, 2020, 21:19 Jonathan Buzzard wrote: > On 19/11/2020 15:34, Caubet Serrabou Marc (PSI) wrote: > > Hi, > > > > > > I have a filesystem holding many projects (i.e., mounted under > > /projects), each project is managed with filesets. > > > > I have a new big project which should be placed on a separate filesystem > > (blocksize, replication policy, etc. will be different, and subprojects > > of it will be managed with filesets). Ideally, this filesystem should be > > mounted in /projects/newproject. > > > > > > Technically, mounting a filesystem on top of an existing filesystem > > should be possible, but, is this discouraged for any reason? How GPFS > > would behave with that and is there a technical reason for avoiding this > > setup? > > > > Another alternative would be independent mount point + symlink, but I > > really would prefer to avoid symlinks. > > This has all the hallmarks of either a Windows admin or a newbie > Linux/Unix admin :-) > > Simply put /projects is mounted on top of whatever file system is > providing the root file system in the first place LOL. > > Linux/Unix and/or GPFS does not give a monkeys about mounting another > file system *ANYWHERE* in it period because there is no other way of > doing it. > > JAB. > > -- > Jonathan A. Buzzard Tel: +44141-5483420 > HPC System Administrator, ARCHIE-WeSt. > University of Strathclyde, John Anderson Building, Glasgow. G4 0NG > ___ > gpfsug-discuss mailing list > gpfsug-discuss at spectrumscale.org > http://gpfsug.org/mailman/listinfo/gpfsug-discuss > ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
Re: [gpfsug-discuss] Mounting filesystem on top of an existing filesystem
On 19/11/2020 15:34, Caubet Serrabou Marc (PSI) wrote: Hi, I have a filesystem holding many projects (i.e., mounted under /projects), each project is managed with filesets. I have a new big project which should be placed on a separate filesystem (blocksize, replication policy, etc. will be different, and subprojects of it will be managed with filesets). Ideally, this filesystem should be mounted in /projects/newproject. Technically, mounting a filesystem on top of an existing filesystem should be possible, but, is this discouraged for any reason? How GPFS would behave with that and is there a technical reason for avoiding this setup? Another alternative would be independent mount point + symlink, but I really would prefer to avoid symlinks. This has all the hallmarks of either a Windows admin or a newbie Linux/Unix admin :-) Simply put /projects is mounted on top of whatever file system is providing the root file system in the first place LOL. Linux/Unix and/or GPFS does not give a monkeys about mounting another file system *ANYWHERE* in it period because there is no other way of doing it. JAB. -- Jonathan A. Buzzard Tel: +44141-5483420 HPC System Administrator, ARCHIE-WeSt. University of Strathclyde, John Anderson Building, Glasgow. G4 0NG ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
[gpfsug-discuss] Mounting filesystem on top of an existing filesystem
Hi, I have a filesystem holding many projects (i.e., mounted under /projects), each project is managed with filesets. I have a new big project which should be placed on a separate filesystem (blocksize, replication policy, etc. will be different, and subprojects of it will be managed with filesets). Ideally, this filesystem should be mounted in /projects/newproject. Technically, mounting a filesystem on top of an existing filesystem should be possible, but, is this discouraged for any reason? How GPFS would behave with that and is there a technical reason for avoiding this setup? Another alternative would be independent mount point + symlink, but I really would prefer to avoid symlinks. Thanks a lot, Marc _ Paul Scherrer Institut High Performance Computing & Emerging Technologies Marc Caubet Serrabou Building/Room: OHSA/014 Forschungsstrasse, 111 5232 Villigen PSI Switzerland Telephone: +41 56 310 46 67 E-Mail: marc.cau...@psi.ch ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
