Installer changes on master (does not effect release)
dillon at apollo.backplane.com
Mon Dec 14 11:53:40 PST 2015
Master has gotten an installer revamp w/regards to the partition
Previously the installer used radically different arrangements for UFS
vs HAMMER. UFS put an integrated boot+root on partition 'a', swap on 'b',
and HAMMER put boot on 'a', swap on 'b', and root on 'd'. HAMMER installs
also created a whole bunch of PFS's for various major directories such
The new setup is more uniform. An 'a' boot, 'b' swap, 'd' root, and
'e' /build is created whether UFS or HAMMER is chosen. PFS's are no
longer used. Instead, major directories which generally do not have
to be backed up (such as /usr/obj) are put on /build and null-mounted
to their appropriate places via the fstab. Major directories which
typically do need to be backed up, such as (most of /var), /home, /usr,
and /usr/local remain on the root filesystem.
The new setup handles small drives (typically < 40GB) by not creating
a separate /build partition. It still creates the /build directory
infrastructure on the root filesystem and still creates the null-mounts,
making it relatively easy for the user to manage later on if/when moving
to a setup with more storage.
I've been using this scheme very successfully at home and on servers
for more than a year now and really like the flexibility and ease of
management. The null mounts are a lot easier for users to manage than
the hammer PFS's, and the separation reduces the chances of the root
filesystem becoming corrupt during a crash.
These changes also allow UFS installs to use encrypted roots which they
could not before. While we recommend HAMMER over UFS generally, there
are still a few cases where UFS is more convenient, such as on small
storage media / USB flash drives.
<dillon at backplane.com>
More information about the Users