Notes on DEVFS serial number support
dillon at apollo.backplane.com
Wed Aug 5 22:18:50 PDT 2009
Note: With these commits a full world & kernel build is required to
get the new features. Multi-volume HAMMER mounts specifying devtab
labels won't work yet (I'm not sure how best to parse them), but
they should work using serno/* paths.
My recommendation here is that people not worry so much about mounting
by serial number unless they have a bunch of drives. Ultimately this
will become a very powerful feature as networked drive support is added.
For now its claim to fame is to remove issues with drive unit iterations
when a drive is removed.
Also note that vinum is not operational in master at the moment.
DEVTAB - Add mountroot & fstab support for serial numbers, and devtab.
* The vfs.root.mountfrom /boot/loader.conf variable may now specify
devfs aliases, allowing it to specify root mounts by serial number.
Here is an example:
Note that vfs.root.mountfrom may NOT currently specify /etc/devtab labels.
* /etc/fstab may now specify devfs relative paths (such as serial numbers)
as well as /etc/devtab labels. A ".suffix" may be used to extend the
translation so /etc/devtab only needs to specify the base label.
# Device Mountpoint FStype Options Dump Pass
driveA.s1d / hammer rw 1 1
driveA.s1b none swap sw 0 0
driveA.s1a /boot ufs rw 1 1
serno/L41JYE0G.s1f /fubar hammer rw 1 1
driveA serno L41JYE0G
<dillon at backplane.com>
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