Along these lines .. does a Linux filesystem on a RO minidisk reflect any changes at all if changes are made by a user with RW?
Is a deactivate/activate necessary? re-LINK? remount? Anyone know the minimum necessary action to see changes? Thanks - Scott On Tue, Mar 10, 2009 at 9:27 AM, Edmund R. MacKenty < [email protected]> wrote: > On Tuesday 10 March 2009 11:17, Eric Mbuthia wrote: > >I have the updated all the necessary Linux configuration files to bring > the > > server up as read only - with the "system personality" directories > mounted > > on a separate mdisk(s) as read+write (/local /etc /root /srv... etc) > > > >Everything from a Linux perspective looks fine > > > >When I change the VM mdisk that has the read only files from rw to ro - I > > get the I/O error below during boot - even though the server comes up > with > > all the necessary services > > You have to also tell Linux that the disk is read-only. Did you add the > "ro" > option to the line for that filesystem in /etc/fstab? If not, it tries to > write to that filesystem, which is what is causing those errors. > > Linux usually updates the "last access time" metadata on each file after it > is > read, causing writes to a device when you think you are only reading from > it. > If you mark the filesystem as read-only as described above (or add > the "noatime" option to a writable filesystem), Linux will not attempt to > update the last access time on files. > > >My question is whether anyone out there is running with the read only > mdisk > > attributed to ro (I understand that from a VM perspective it is not a > good > > idea to have an mdisk shared between multiple guests as read/write) > > [cid:_1_05A39EF405A398E80053D70585257575] > > Yes. My Provisioning Expert tool creates read-only mdisks all the time, > because it sets up shared DASD by default. Works just fine, because I tell > both z/VM and Linux that the device is read-only. They both need to know > about that. > - MacK. > ----- > Edmund R. MacKenty > Software Architect > Rocket Software > 275 Grove Street · Newton, MA 02466-2272 · USA > Tel: +1.617.614.4321 > Email: [email protected] > Web: www.rocketsoftware.com > > ---------------------------------------------------------------------- > For LINUX-390 subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO LINUX-390 or > visit > http://www.marist.edu/htbin/wlvindex?LINUX-390 > ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
