Hello,
I need a program that will synchronize a big folder between 2
computers over the Internet. The operating system on both is Windows
2000.
The folder to be synchronized is 60 GB, and constantly has people
adding or deleting files, so it would be best if it could somehow
detect changes automatically rather than search for them.

Anyhow, I need something that is inexpensive, $100 US or less, please.
If you see anything for more than that then let me know, altough it
probbly isnt an option.

Please do not recommend FTP synchronization. I know about it and it is
not viable for certain reasons.

A program that uses encryption is preferred.

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Request for Question Clarification by aht-ga on 25 Mar 2004 13:19 PST

cym-ga:

Can you clarify how the two servers are physically connected to the
Internet, and therefore each other? For example, are they part of a
WAN, are firewalls involved, proxies, etc. Do you have static IP
addresses, what sort of bandwidth is available... you get the idea, I
hope.

Please let me know the details of the connection between the two
servers, so that I may refine my search and recommendation to the most
appropriate options.

Regards,

aht-ga
Google Answers Researcher

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Clarification of Question by cym-ga on 25 Mar 2004 16:02 PST

The servers have static IPs, but are not on the same WAN.

They are both on powerful Internet connections in colocation centers,
and are typically capable of 200 kilobytes per second, both up and
down.

They both have firewalls, obviously. The firewalls can be configured,
though the firewalls do allow access to the servers via NAT. This
should not be a problem, as the NAT can be configured. There are no
proxies.
While the IPs are static, the software may be used with servers
without IPs that utilize dynamic DNS.

The connection is via TCP/IP

As the servers are in colocation centres, and therefore must have high
availability, then the likelihood that a sub-$100 solution will meet
your needs is low. In the <$100 part of the market, the solutions are
geared towards client-level synchronization; while some of the
software can be used on servers that can be restarted periodically,
generally anything that is robust enough to run as a service 24x7 will
be several hundreds of dollars per license (and you will need two
licenses to cover the two machines).

In the >$100 segment, one that I have used myself is SureSync
(http://www.suresync.com ). It meets all of your stated requirements,
but goes for US$495/server. Well worth it, in my opinion, but easily
ten times your budgeted amount of $100.

In the <$100 segment, a low-cost solution is FolderClone
(http://www.folderclone.com ). At US$28, though, it is geared towards
workstation folder synchronization as opposed to high-availability
server mirroring. It uses Windows' native API for reading and writing
files across a network connection; while it can use TCP/IP over the
Internet, the file transmissions will not be encrypted. Technically,
you can install this on a single workstation, and have that
workstation connect to both servers over the Internet; then, the
workstation would be responsible for detecting changes on either
server, and mirroring those changes across to the other server.
However, because this is inherently insecure and cannot be sustained
if there are a lot of changes going on all the time, I cannot
recommend this to you given your criteria.

Therefore, I am posting this information here as a comment, in case
any of it is of value to you. If you wish to revise your criteria, I
can provide you with an Answer centered around SureSync as the
solution.

Regards,

aht-ga
Google Answers Researcher

As you are looking for a cheap solution, try the tool RSYNC. It uses
SSH (encryption) to syncronize servers. It compresses the data for
you. And it also syncronizes patitial files (if you only change a few
pages in a large Text document).

I am using it on a 256kbit DSL connection everyday (as backup). Both
sides have about 10 GB of data. Syncronization takes about 1 to 2
minutes. But if you have large changes, it will be slower.

!! Please be aware that the wrong commandl-line switches will wipe
your entire harddrive. Please test it very carefully !!

For the Windows version of RSYNC you might want to take a look at this page:
http://www.itefix.no/cwrsync/ (new version)
or
http://optics.ph.unimelb.edu.au/help/rsync/rsync_pc1.html (old
version, but very very small)

The simplest answer on Windows is to use Active Directory. You need to
setup a Domain Controller (DC) on any Windows Server platform.

If this is not viable, you optionally have the following:

* Concurrent Versioning System (CVS)
* Subversion (some say it is superior to CVS)

With CVS you can schedule CVS repository synchronization at any time
you choose. With Active Directory you can use a Distributed File
System, which is the preferred route. It also supports encryption and
integrates with NT Authentication (NTLM) or Kerberos.