defragcron(8)defragcron(8)NAMEdefragcron - Schedules AdvFS file domains for defragmenting
/usr/sbin/defragcron [-p] [-q] [-t nnn] [-b hh:mm] [-a hh:mm] [-l path‐
/usr/sbin/defragcron [-p] [-q] [-t nnn] [-T mm] [-l pathname]
Specifies that the domains are to be defragmented in parallel. If not
specified, the default is to serially defragment the domains. Suppress
informational messages. If not specified, the default is to produce
informational messages. Specifies the aggregate I/O performance
threshold, the point at which the domain should be defragmented. A
number from 1-100. If not specified, the default is to always defrag‐
ment the domain.
The performance threshold is based on the value returned by the
defragment -nv command. If this value is lower than or equal to
the value specified here, the domain is defragmented. If speci‐
fied, the utility will not run before this time and will return
an error if the time is not yet reached. Specify time values
using the 24-hour clock. If not specified, the default time is
01:00. If specified, the utility will not run after this time,
and will return an error if the time has been passed. Specify
time values using the 24-hour clock. If not specified, the
default time is 05:00. Specifies an exact time interval, in
minutes, for the defragment utility to run. If not specified,
there is no default.
If you use this option, its action overrides the before and
after time checking of the -a and -b options. Specify the -l
option to direct messages to log files in the specified direc‐
tory. One log file is generated for nonspecific messages and
separate log files are generated for each domain that is defrag‐
If the option is not specified, the default action is to not
produce log files for the messages (which then are directed to
the standard output device).
If the option is specified, you also must specify a pathname for
the directory into which the log files are to be written. The
default directory, as specified in the root crontab entry, is
The names of the log files have the following format:
domain1.log, domain2.log, ..., and so on, one file for each
active domain, plus a file, defragcron.log for the nonspecific
messages. If you have named a domain defragcron, messages for
that domain are written to the nonspecific messages in the
Specifies one or more AdvFS file domains. If no domains are specified,
the default action is for the utility to defragment all active AdvFS
The defragcron utility runs the defragment utility to a schedule that
you specify on all active AdvFS file domains or on the active domains
The typical use of this utility is to run it as a command in the cron
daemon. See cron(8).
Unless the domain is listed in the comand line, the utility does not
attempt to defragment inactive file domains (those which have no
mounted filesets). It can try to defragment file domains that have
some mounted and some unmounted filesets. In this case, the utility
You must have root user privileges to run this utility.
All restrictions for the defragment utility are in effect for the
The utility returns a 0 (zero) on success. Otherwise, it returns a 1
and an error diagnostic.
The following example defragments all active domains that have an
aggregate I/O performance threshold less than or equal to 60 for an
interval of 240 minutes: # /usr/sbin/defragcon -q -t 60 -T 240
The command's path. The path of the defragment utility.
Commands: crontab(1), cron(8), defragment(8)defragcron(8)