Saturday, March 25, 2006 

SyncToy for Windows XP

SyncToy for Windows XP is a simple bit of software from Microsoft that fits the bill for my home PC backups. Give it any number of folder pairs, and configure how you'd like the two folders to remain in sync. There are 5 different synchronisation methods, each differ in the way they treat deleted/modified/new files. For example; to back up my digital photos I have a D:\Photos folder and an E:\Photos folder on two different physical disks. I can configure sync toy to keep the two folders in sync, and I'm protected from a hard disk failure.

The sync doesn't happen automatically, which is something I like about it. Alternatively there are instructions on how to use the Windows Scheduled Tasks to schedule recurrent SyncToy runs.

If I got really keen I could set-up folder pairs to sync everything I'd want for a rebuild (installers, coding projects, documents, bookmarks, photos, etc) with an external HD. I'll have a back-up and rebuilding my PC would be infinitely easier.

Just experimented synchronising with a CDRW. When you select the CD drive from the folder dialog the folder actually selected is in %USERPROFILE%\Local Settings\Application Data\Microsoft\CD Burning. If you try manually typing the CD-ROM drive name, you get an error telling you to 'make sure external devices are attached'. The first time you attempt to synchronise, the files get delivered to the "CD Burning" folder, and you get the disk burning pop-up.

Everything gets burnt to the disk okay. But second time around the "CD Burning" folder is empty - so SyncToy attempts to copy every file again, and you get an error when you try burn the CD. Everything does work okay if you first format the CDRW, which I could put up with. Ideally it'd be great if SyncToy itself could handle the CD burning process, and support spanning disks. Otherwise I'm very happy with this little discovery. Thanks to Ellecer for getting me onto this!



Another link drop


Monday, March 13, 2006 

States Pass Thousands of Info Restriction Laws

Wow, I just saw this really thought provoking comment on the the Slashdot article: States Pass Thousands of Info Restriction Laws.

"The smart way to keep people passive and obedient is to strictly limit the spectrum of acceptable opinion, but allow very lively debate within that spectrum - even encourage the more critical and dissident views. That gives people the sense that there's free thinking going on, while all the time the presuppositions of the system are being reinforced by the limits put on the range of the debate." Noam Chomsky

I always knew there was something sinister about Speaker's Corner in London..

Saturday, March 04, 2006 

Update: Remote Desktop + SSH/Putty

This is an update to the article below: Remote Desktop + SSH/Putty.

After reading this article on accessing a machine behind a firewall [pdf link] it occured to me that the configuration in the previous post could also be used to access a work PC from home.

When you add a 'tunnel' via the dialog above, you can add either a local or remote tunnel. A local tunnel is like saying "I want to create a 'wormhole' port x on this PC which emerges at port y on at the SSH server". My configuration above has local ports 3390 and 3391 configured to 'emerge' at the Remote Desktop ports on my two home machines.

A remote tunnel tells the SSH server to create a 'wormhole' port on the SSH server. The remote port above points port 3400 on my SSH box to port 80 on the client machine. So I can open a browser on my SSH machine, and browse localhost:3400 and see the webserver on my work PC.

This is all explained well in the Putty documentation.



Remote Desktop + SSH/Putty

If you ever want to open your PC for remote access - but want something relatively secured. Here is a good solution using: OpenSSH, Putty, and public/private key authentication. Putty can access your OpenSSH server via a HTTP proxy on port 443, which is handy if you are behind a firewall (i.e. at work). Took a couple of articles to get it going: Nothing like this works straight away, so here's a logical order of steps to get things going:
  • Install OpenSSH on the target machine, and install Putty on a non-firewalled machine somewhere. Go though the steps in the first document, and forget everything about the HTTP proxy stuff. If you can click 'Open' in Putty and see the 'Login:' prompt you're on the right track.

    Luckily for me a friend opened up VNC for me on his home machine so I could test this step. If things aren't working here: make sure port 433 is being forwarded on your router (and you ISP doesn't block it!), and you've set up an exception in Windows Firewall to let port 443 in. Experiment with a different port number - make sure you configure the right port number in sshd_config, your router, and windows firewall.
  • Now that works try the HTTP proxy bit.
  • Happy with that? Now try setting up the public key authentication. I had some troubles here with OpenSSH being very sensitive to config settings. After changing a setting the SSH terminal window (above) wouldn't display anything. Keep a back-up of the config file when it works!