been changed and are in need of a transfer. Without this option, rsync
uses a "quick check" that (by default) checks if each file's size and time
of last modification match between the sender and receiver. This option
-changes this to compare a 128-bit MD4 checksum for each file that has a
+changes this to compare a 128-bit checksum for each file that has a
matching size. Generating the checksums means that both sides will expend
a lot of disk I/O reading all the data in the files in the transfer (and
this is prior to any reading that will be done to transfer changed files),
automatic after-the-transfer verification has nothing to do with this
option's before-the-transfer "Does this file need to be updated?" check.
+For protocol 30 and beyond (first supported in 3.0.0), the checksum used is
+MD5. For older protocols, the checksum used is MD4.
+
dit(bf(-a, --archive)) This is equivalent to bf(-rlptgoD). It is a quick
way of saying you want recursion and want to preserve almost
everything (with -H being a notable omission).
For a list of the possible escape characters, see the "log format" setting
in the rsyncd.conf manpage.
+The default FORMAT used if bf(--log-file) is specified and this option is not
+is '%i %n%L'.
+
dit(bf(--stats)) This tells rsync to print a verbose set of statistics
on the file transfer, allowing you to tell how effective rsync's delta-transfer
algorithm is for your data. This option is equivalent to bf(--info=stats2)
will have no effect. The bf(--version) output will tell you if this
is the case.
-dit(bf(--checksum-seed=NUM)) Set the MD4 checksum seed to the integer
+dit(bf(--checksum-seed=NUM)) Set the checksum seed to the integer
NUM. This 4 byte checksum seed is included in each block and file
-MD4 checksum calculation. By default the checksum seed is generated
+checksum calculation. By default the checksum seed is generated
by the server and defaults to the current code(time()). This option
is used to set a specific checksum seed, which is useful for
applications that want repeatable block and file checksums, or