-c Option

Dick Streefland dick.streefland at altium.nl
Fri May 31 09:34:02 EST 2002

On Thursday 2002-05-30 12:43, Michael Montero wrote:
| 	That's great news.  I believe this applies to me just fine and I
| can turn off the checksum.  Quick question....can anyone explain to me
| when the data in a file might change without changing the mtime, ctime or
| size?  I'm not sure I've ever come across that before.  An example might
| help me determine if I can safely remove -c.

I ran into a situation where I had to use the -c option. I use two
rsync commands to install Linux onto new PCs, the first one to "clone"
a system, and a second one to update a few host specific files such as
/etc/hostname, /etc/network/interfaces etc. The host specific files
are automatically generated from template files, using a compact
description of each machine. This script runs so fast that multiple
files will get the same mtime. So, it is possible that some host
specific files are not updated by the second rsync command, because
the mtime is the same as the mtime on the master.

On one occasion, a machine came up with the same hostname as the
master machine after the installation. Furtunately, the file with the
IP number was correct!  I now use the -c option on the second rsync,
which is not a problem, because the number of files is very limited.

BTW: I previously used NFS with find/cpio to clone Linux installations,
     but rsync is *way* faster, 2-3 times faster on a 10 Mb network.

Dick Streefland                      ////             Altium Software BV
dick.streefland at altium.nl           (@ @)          http://www.altium.com

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