Back when I administered VAXen running BSD UNIX at FileNet, “just” 25 years ago or so, we didn’t have a high speed internet connection to use in transferring files between computers. I used a bank of Racal-Vadic 2400 baud modems to run UUCP and shuffle email and usenet articles around. With five modems in the bank, felix the VAX 750 grew to be a modest UUCP hub in SoCal. Today we measure our internet connections in megabits or Mbps, millions of bits per second, instead of baud. I am typing this on a cable modem connection that just achieved 11.4 Mbps downloading data and 1.7 Mbps uploading data. By comparison, felix the VAX had about 0.0024 Mbps of bandwidth, and downloading did not go any faster than uploading.
We used to say, never underestimate the bandwidth of a station wagon full of magnetic tapes. With just 0.0024 Mbps of bandwidth available, it was completely impractical to transfer large files across “the net.” Instead, we would write the files to 10.5″ reels of magnetic tapes and drive them to their destination by car.
It would take several tapes, and several hours, to “back up” a single 67 MB, washing machine sized, RM03 disk drive. Once the tapes were written, we would bundle them into the nearest car and take a road trip across town to where they needed to be. Then would begin the (usually slower) process of reading the tapes into the new computer. It was way faster to move data by “station wagon” than pretty much anything else.
Flash forward to 2010. On Tuesday, I had 62,000 MB of files on a computer in a datacenter in Houston that had to be moved to a new computer in a datacenter on the east coast. I live in the middle of the country (St. Louis) and do not have ready access to either datacenter. Through the miracles of the internet, I logged into the Houston computer and typed one command:
rsync -az /backup/htn/ [email protected]:/backup/htn
About eight hours later, with no intervention from me, all of the files had been replicated onto the new machine. I had just moved 1,000 times as much data as one of felix’s entire disk drives in a fraction of the time and with virtually no effort.
Yup… life is good.
