The 'rolling checksum' part of the implementation is brilliant.
I have often wondered why it is that rsync is so life-saving-ly quick and how it is that a few small changes to a massive file (e.g. from mysqldump) can be copied up to a server from the slow end of an ADSL line so quickly. Now I know about the 'rolling checksum' I can see what is going on.
Note that I work with people who use 'FTP' to copy files, or even worse, people who find FTP too complicated and have to send me files on a 'Dropbox' thing so I can download them and upload them for them, notionally with 'FTP'. (I will use rsync instead, not least for the bandwidth control options).
I have even had micro-managers get me to get FTP to work on the server for them, despite my protestations about it being insecure (which it really is if you use a Windows PC and something like Filezilla).
Obviously I only use rsync and scp. Without aforementioned micro-managed requests I would not even know if FTP was installed on the server side.
My point is that it may be easy for a few folks here to criticise rsync, however, there are a lot of people, from clients to managers and even talented programmers that just don't have a clue about rsync and are stuck in some stone age of using things like FTP.
> (which it really is if you use a Windows PC and something like Filezilla).
What does Windows as a client OS have to do with it? FTP is insecure because it transmits credentials in the clear and because it opens additional ports for the actual transfer of data. Neither of which are a concern of the client.
Thanks for your point - I have just remembered that I have recovered someone's FTP password for them from a TCPIP stream and it was fun but not difficult!
However, of notable attacks I have witnessed recently, the plain text file of Filezilla was the attack vector. Get that and away you go!
[0]: from http://blog.liw.fi/posts/rsync-in-python/ but this site has been on and off regularly, hence the scavenging straight from my browser cache. As of today, the site is up again but the bzr repo is out of order (and bzr is not exactly popular).
I have often wondered why it is that rsync is so life-saving-ly quick and how it is that a few small changes to a massive file (e.g. from mysqldump) can be copied up to a server from the slow end of an ADSL line so quickly. Now I know about the 'rolling checksum' I can see what is going on.
Note that I work with people who use 'FTP' to copy files, or even worse, people who find FTP too complicated and have to send me files on a 'Dropbox' thing so I can download them and upload them for them, notionally with 'FTP'. (I will use rsync instead, not least for the bandwidth control options).
I have even had micro-managers get me to get FTP to work on the server for them, despite my protestations about it being insecure (which it really is if you use a Windows PC and something like Filezilla).
Obviously I only use rsync and scp. Without aforementioned micro-managed requests I would not even know if FTP was installed on the server side.
My point is that it may be easy for a few folks here to criticise rsync, however, there are a lot of people, from clients to managers and even talented programmers that just don't have a clue about rsync and are stuck in some stone age of using things like FTP.