Randy Kramer wrote:
>
> There are some subtleties to rsync that you may need to know at times.
> It works well, but there is a gotcha for large files -- IIRC, if the
> rsync operation is interrupted, the entire file is thrown away at the
> receiving end. This includes (IIRC) the bad copy that you started
> with.
No, no, no!! This must have been corrected. This has not been my
experience. I have downloaded many iso CD images and rsync has
always picked up the threads correctly after an interruption. It
does give a progress indication starting at the start of the file
leading up the resume point, after which it slows down considerably
as you would expect.
> So, if an rsync operation is interrupted every two hours, and the
> rsync operation cannot be completed in two hours, you lose not only the
> corrections accomplished during that two hours but also your original
> file. (So, at the very least, you want to have a backup copy of your
> original "bad" file in a safe location so you can restart with that
> after an interruption rather than reloading from scratch. (Rsync will
> essentially revert to a ftp operation if there is no file on the
> receiving end.)
Note that if you use this technique you must use rsync as the local
copy utility to both make and restore the backup. Otherwise rsync
will not recognise it and start a fresh download - the copy utilities
and Konqueror do NOT preserve the datestamps on the file (GRRRRR!!).
> Rsync does use a lot of computational power on both computers, but,
> since the bottleneck is the link connecting them, usually that
> processing power is not an issue. I have had problems transferring
> large files when the server end apparently disconnected me because the
> rsync process was doing a lot of calculation without transmitting any
> data (at least, that's what I suspect was happening -- the server
> presumably thought the rsync process was hung). In this case you get a
> rather misleading message, which I can't recall right now.
>
> Ron (IIRC) has written sort of a wrapper around rsync that makes it
> easier / better for use with cooker. I've never tried it.
Yes, I originally wrote one, which has now been taken over by Troels
Liebe Bentson. It is fast and very popular and is available for
download (GPL licence) on my web site (see below). It provides
selectivity of what you download, initially supplied set to English
RPMs only (thus saving over 200 MB of download), but all this is
customizable. It also upnames older RPMs at your end so that for
updates rsync is forced into its patch-in-place mode instead of doing
a full download.
--
Ron. [au]
Kindly note my new email address: [EMAIL PROTECTED]
and new web site: http://www.ains.net.au/~ronst/
