I senaste numret av Datormagazin (nummer 8 / 2010) finns en artikel som jag skrivit via mitt företag New Seed. Som vanligt är det en förhållandevis teknisk artikel, denna gång om hur man skapar sitt eget lilla backup-kluster av några gamla datorer. Såhär i efterhand när jag läser artikeln känner jag att jag som vanligt har varit på tok för “effektiv” och texten känns väldigt informations-packad.
Artikeln tar upp hur man använder SSH och rsync i kombination för ett automatiskt backup-system som kör nattetid. Tack vare SSHs möjlighet till automatisk autentisering och rsyncs effektiva kopiering över nätverk kan man få en riktigt bra lösning. Köp senaste numret och läs själva hur!
Few pieces of software have managed to make a deep impression on me, through my ten years I can only remember a few moments I was really impressed with what I had just found or tried. Here are my “highlights” in no particular order. I might want to add that some of these events took place long ago.
The operating in itself was perhaps not so impressive but the hardware support was like nothing I had never seen before. This was put to its edge when I one day moved a harddrive with Windows 98 from one computer to another (due to memory failure on the original computer) and I was deeply impressed that the operating system quickly adapted to the new hardware, installed new drivers, rebooted and then worked!! Not only did it work for the moment but I remember that computer running for at least a month or so before I reinstalled it anyway since I wanted to be sure as to have no internal conflicts within the operating system. If I had tried this with Windows 95 or earlier I’m sure the computer would have found a way to vaporize, explode or otherwise mutilate itself.
Where there anyone not impressed when they first saw Google Earth? It’s an amazing piece of software, one thing is to invent it but it’s a whole other thing to acctually implement it and get it to work! Truly amazing.
I do not know how old this command is, I just found it a year or so ago, but it is like the swizz army knife of backups! I found that I could with ease sync very large folders over remote connections using SSH and not have to worry to much about transmission payload! This wonderful command calculates the difference between the two folders, at both ends, and then syncs the changed contents. While this might not be very impressive rsync takes it one step further, if a file differs it also calculates which parts of the file have changed and only sends the changes! In essence, that 2 Gb log file that keeps changing every night can still be synced since rsync will only keep sending the changes to the file and not the whole file.
I always knew that virutal servers where nothing for me. Boy was I wrong! Almost by misstake I tried out VMWare Server when it became free to use in development and I’ve not stopped using it since! The ability to host several development machines and try out different configurations without have to worry about breaking the servers is great. Just snapshot a server, try whatever you want and if you do not like the result just revert back to the snapshot! The bonus that it hosts several of my development environments on a single PC (or laptop!) is not something I even think about.