John; Be very careful with a sector-by-sector backup utility if you decide to use an SSD. Solid State Drives constantly are moving sector locations around in order to avoid writing to the same flash location too many times. This occurs whenever a file needs to be updated or rewritten, and is especially true of the directory sectors. Because of this a backup may catch a file relocation in mid move, or more often catch a directory update while it is being moved, The result will be a completely useless backup. We discovered this recently when a friend needed to restore his system from a backup.
The answer is to use a normal file-oriented backup instead of a sector- by-sector backup. Those backups are very much useful when needed. With the trend to replace disks with SSDs, especially in laptops, this will become very important. For those wondering, TIme Machine is indeed a file backup and not sector-by-sector. I recommend it whole heartedly! Jack Brindle, W6FB On May 22, 2012, at 11:22 AM, John Ragle wrote: > Hi, Jim... > > There are several programs that make literal copies (mirror > copies) > of disk contents. This includes the OS and all program files as well > as > data... > > I happen to have been using one called "Macrium Reflect > Professional" for the last few years. It produces a bit-for-bit > literal > image (a mirror copy) of the TOTAL contents of one or more hard > drives, > and can re-load such images. It does much more than copy data files. > At > present, I am using a PC with 2 inboard hard drives, each of 250 GB > capacity. One of these is my WIN7 Ultimate OS and associated files > (including programs, etc), and is about 80 GB in total content. The > second is my Ubuntu 11.10 OS and a somewhat smaller collection of > files > (including programs, etc.) I back up the former almost daily onto a > 1 TB > external USB hard drive, and somewhat less frequently onto a Sandisk > 64 > GB stick...the 80 GB on the C:\ drive fit nicely onto the 64 GB stick > with the compression used by Macrium. The rate-determining step in > these > USB-based devices is the USB transfer rate itself; 80 GB takes about > 25 > minutes to back or restore, and I do it last thing at night, letting > Macrium close down the PC when finished. > > If I had a third drive bay, I would probably choose to back up > onto > a third drive...hard drives have become so inexpensive that you can > practically use them like floppy drives. This would be significantly > faster, about 10-12 minutes for the 80 GB contents of C:\ > > A while ago, I used a Sparc 20 with a shoebox tape drive and "DAT > Tapes," but that had little to do with my ham radio operation. These > were unsatisfactory because the error rate was significant. I also > tried > using an elderly PC as a network server at home on our LAN. That too > was > somewhat cumbersome. My wife is an active software developer (vide the > "OWL" system from Cengage), and separately uses a version of Macrium > onto a 1 TB external drive, but much of her work is stored on a > corporate "cloud," and hopefully backed up there as well. > > I do not have a high opinion of "Windows Restore" -- it is > significantly more involved to use than is Macrium Reflect. > > An advantage (to me the most significant one) of doing a bit-image > backup is that when it comes time to restore program files (i.e. .exe > files, etc), one does not have to search out the distribution media > and > play "baking cookies" with those media for hours to rebuild the > system. > > A disadvantage of doing a bit-image backup is that in the absence > of good "garbage collection" one keeps using the same general > structure > over and over again...a case can be made for rebuilding from scratch > (not from the bit image) on a regular basis...some have suggested > once a > year, at least. > > The Linux crowd can tell you of several useful Linux based > utilities for total backup, restore, partitioning, etc...I won't > enumerate them here, though many of them are very useful. > > In general, I don't favor running anything off the "cloud." My ISP > is sometimes down for 1 or more hours, and that mode of dis-operation > would leave me in the cold. Moreover, in view of the spate of > successful > hacking attacks, I don't trust cloud security. If I disconnect from > the > internet, the only ways someone can hack me are via my WiFi or to > physically break into my home. I have taken pains to barricade the > former. The latter takes care of itself in the usual way. > > Hope this answers your questions.... > > John Ragle -- W1ZI > > ===== > > On 5/22/2012 12:59 PM, James Robbins wrote: >> John, >> >> >> >> Could you be more specific about your process for "bit image >> backup" and >> "safe sectors"? Program you use? What files you choose to >> backup? Whether >> Windows Restore program is or is not a suitable substitute? Thanks. >> >> >> >> 73, >> >> Jim Robbins >> >> N1JR >> >> >> >> "It is vitally important to practice "safe sectors." A bit image >> backup >> takes only a few minutes, and can be made on an auxiliary hard >> drive or a >> jump drive." >> >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> >> >> > > -- > Sent from my lovely old Dell XPS 420 > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
