On Fri, Jan 28, 2011 at 03:52:53PM -0800, Travis H. wrote: > So I'm curious if there's something in OpenBSD that's similar to the > "mount -o bind /dir1 /dir2" to make dir1 appear where dir2 is.
For those who asked, one sample use is for something like this: Starting with the 2.4-series Linux kernels, it has been possible to mount a filesystem simultaneously in two different places. "Aha!" you might think, as I did. "Then surely we can mount the backups read-only in /snapshot, and read-write in /root/snapshot at the same time!" Alas, no. Say your backups are on the partition /dev/hdb1. If you run the following commands, mount /dev/hdb1 /root/snapshot mount --bind -o ro /root/snapshot /snapshot then (at least as of the 2.4.9 Linux kernel--updated, still present in the 2.4.20 kernel), mount will report /dev/hdb1 as being mounted read-write in /root/snapshot and read-only in /snapshot, just as you requested. Don't let the system mislead you! In the example above, the second mount call will cause both of the mounts to become read-only, and the backup process will be unable to run. Scratch this one. Update: I have it on fairly good authority that this behavior is considered a bug in the Linux kernel, which will be fixed as soon as someone gets around to it. If you are a kernel maintainer and know more about this issue, or are willing to fix it, I'd love to hear from you! -- Effing the ineffable since 1997. | http://www.subspacefield.org/~travis/ My emails do not usually have attachments; it's a digital signature that your mail program doesn't understand. If you are a spammer, please email j...@subspacefield.org to get blacklisted. [demime 1.01d removed an attachment of type application/pgp-signature]
