>>> On 8/25/2010 at 08:26 AM, Christian Paro <[email protected]> wrote: > As for ext2 vs ext3 for the read-only file system, there is a question of > whether it's a disk which is to be written to once and then linked to and > mounted read-only by everyone (in which case ext2 makes the most sense, with > ext3 adding nothing but unnecessary overhead), or a disk which is regularly > written to by one system - which you for some reason want be able to link to > and mount read-only from another (in which case the ext3 journal does still > serve a purpose while the disk is being accessed in write mode by that first > system).
This would be a very dangerous practice, and one I always tell people to never use. If a file system is going to be shared between Linux systems, it needs to be mounted read-only by all systems, including the "owner" of it. (Unless we're talking about clustering file systems, which we're not.) Given the way Linux delays write I/O you're likely to never have a consistent view of the file system from anywhere other than the owner. Throw in z/VM minidisk caching and the problem can get much worse very quickly. To me, the bottom lines is that if you want to share non-clustering file systems, no one can have it mounted read-write. If that functionality is necessary, then you need to go with a cluster file system and all the additional infrastructure that entails. With SLES11 that was made pretty easy to do, and SLES11 SP1 improves on that. The SLE High Availability Extension is a no additional cost option for anyone with a valid SLES subscription. Use it, and keep your data intact. Mark Post ---------------------------------------------------------------------- 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 more information on Linux on System z, visit http://wiki.linuxvm.org/
