Re: mtime vs ctime
On 8 September 2015 at 15:21, Kevin Korb wrote: > I would need to see both your existing rsync command line and the > output of --itemize-changes when such an occurrence happens before I > can really understand what is happening. > > In the end, if you have any output at all the bare minimum should be > - --itemize-changes. --verbose is utterly useless without it. Thanks again, Kevin, I'll have a look at the python wrapper script (it predates me by about 1.5 years). -- Please don't top post, and don't use HTML e-Mail :} Make your quotes concise. http://www.georgedillon.com/web/html_email_is_evil.shtml http://www.catb.org/jargon/html/email-style.html -- Please use reply-all for most replies to avoid omitting the mailing list. To unsubscribe or change options: https://lists.samba.org/mailman/listinfo/rsync Before posting, read: http://www.catb.org/~esr/faqs/smart-questions.html
Re: mtime vs ctime
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 I would need to see both your existing rsync command line and the output of --itemize-changes when such an occurrence happens before I can really understand what is happening. In the end, if you have any output at all the bare minimum should be - --itemize-changes. --verbose is utterly useless without it. On 09/07/2015 11:10 PM, Andrej wrote: > On 8 September 2015 at 13:57, Kevin Korb > wrote: Hi Kevin. > > >> -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 >> >> The ctime will always be newer or the same as the mtime. This >> is because changing the mtime also changes the ctime as does >> other things like changing the permissions. >> >> Rsync only pays attention to the mtime because rsync can set a >> specific mtime (--times) but setting a specific ctime is >> impossible as it would violate the basic *nix security model. >> Therefore ctime can't be copied, therefore ctime can't ever be >> expected to match, therefore it is useless to rsync. > > If this is the case I don't understand the behaviour I'm seeing > here. The files mtime haven't changed, the time-stamps of the > copies on the backup server and the time-stamp on the iSCSI mount > are the same (the mtime, that is; the ctimes differ, obviously, as > all files have the time-stamp of the mount-event). > > Do you have an explanation? > > >> Rsync should be using the delta transfer algorithm (unless - >> --whole-file) so it really should just be determining what is >> different about the file then transferring those differences. >> --stats would help determine this. > > H ... > > Doesn't look like it to me. > - -- ~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._., - -*~ Kevin Korb Phone:(407) 252-6853 Systems Administrator Internet: FutureQuest, Inc. ke...@futurequest.net (work) Orlando, Floridak...@sanitarium.net (personal) Web page: http://www.sanitarium.net/ PGP public key available on web site. ~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._., - -*~ -BEGIN PGP SIGNATURE- Version: GnuPG v2 iEYEARECAAYFAlXuVCsACgkQVKC1jlbQAQfYPwCcDNClv4gPHI/jdoQVXZO+Suao AwgAnAsnCJurds9A37e22Y6ccuMjOq5l =w8IH -END PGP SIGNATURE- -- Please use reply-all for most replies to avoid omitting the mailing list. To unsubscribe or change options: https://lists.samba.org/mailman/listinfo/rsync Before posting, read: http://www.catb.org/~esr/faqs/smart-questions.html
Re: mtime vs ctime
On 8 September 2015 at 13:57, Kevin Korb wrote: Hi Kevin. > -BEGIN PGP SIGNED MESSAGE- > Hash: SHA1 > > The ctime will always be newer or the same as the mtime. This is > because changing the mtime also changes the ctime as does other things > like changing the permissions. > > Rsync only pays attention to the mtime because rsync can set a > specific mtime (--times) but setting a specific ctime is impossible as > it would violate the basic *nix security model. Therefore ctime can't > be copied, therefore ctime can't ever be expected to match, therefore > it is useless to rsync. If this is the case I don't understand the behaviour I'm seeing here. The files mtime haven't changed, the time-stamps of the copies on the backup server and the time-stamp on the iSCSI mount are the same (the mtime, that is; the ctimes differ, obviously, as all files have the time-stamp of the mount-event). Do you have an explanation? > Rsync should be using the delta transfer algorithm (unless > - --whole-file) so it really should just be determining what is > different about the file then transferring those differences. --stats > would help determine this. H ... Doesn't look like it to me. -- Please use reply-all for most replies to avoid omitting the mailing list. To unsubscribe or change options: https://lists.samba.org/mailman/listinfo/rsync Before posting, read: http://www.catb.org/~esr/faqs/smart-questions.html
Re: mtime vs ctime
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 The ctime will always be newer or the same as the mtime. This is because changing the mtime also changes the ctime as does other things like changing the permissions. Rsync only pays attention to the mtime because rsync can set a specific mtime (--times) but setting a specific ctime is impossible as it would violate the basic *nix security model. Therefore ctime can't be copied, therefore ctime can't ever be expected to match, therefore it is useless to rsync. Rsync should be using the delta transfer algorithm (unless - --whole-file) so it really should just be determining what is different about the file then transferring those differences. --stats would help determine this. On 09/07/2015 09:46 PM, Andrej wrote: > Hi, > > We use an rsync (rrsync, to be precise) based back-up solution. > Every so often an iSCSI based file-system gets brought up and left > connected for the night. After a mount event rsync will back that > volume up, including server TB of data that haven't been modified, > but the ctime is newer than the mtime. Is there a way to stop > this behaviour? > > > Cheers, Andrej > - -- ~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._., - -*~ Kevin Korb Phone:(407) 252-6853 Systems Administrator Internet: FutureQuest, Inc. ke...@futurequest.net (work) Orlando, Floridak...@sanitarium.net (personal) Web page: http://www.sanitarium.net/ PGP public key available on web site. ~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._., - -*~ -BEGIN PGP SIGNATURE- Version: GnuPG v2 iEYEARECAAYFAlXuQHAACgkQVKC1jlbQAQeqJwCg7E7HD15wUcJwvZsvrsSXSoNn 2YgAoKs5htAjdk1JUL7rYzI7QxwUOik/ =EHps -END PGP SIGNATURE- -- Please use reply-all for most replies to avoid omitting the mailing list. To unsubscribe or change options: https://lists.samba.org/mailman/listinfo/rsync Before posting, read: http://www.catb.org/~esr/faqs/smart-questions.html
