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Description: I want to create an usb stick that loads opensuse 11.2 RC1.
/dev/sde is the usb stick.
The iso file corresponds to opensuse live CD.
This is the command I use
Problem solved.
I was running dd under opensuse 11.1 (2.6.27.29-0.1-default
)
When I run the dd under opensuse 11.2 (Rc1) (2.6.31.3-1-desktop) the problem was solved. Most likely was due to the new kernel (?).
Thanks. This is great. However, I found that for creating the dvd images, I had to limit the count to 4400 rather than the suggested 4600.
[later edit]
Alas, in trying to mount and read the created dvds, I found I was unable to. I following the directions for creating the images, and then writing them to dvd via wodim, exactly as written (though, as mentioned above, wodim would not write the images created with the count set at 4600, whereas it did when it was set to 4400). But, trying to mount them gave me the following:
First, the writing of the images (the 3rd, in the following example):
Code:
mark@debian:~/stuff/debs/backup/dvd$ wodim -dev=/dev/hdc --driveropts=burnfree /home/mark/backup_set_3.img
wodim: No write mode specified.
wodim: Asuming -tao mode.
wodim: Future versions of wodim may have different drive dependent defaults.
wodim: Operation not permitted. Warning: Cannot raise RLIMIT_MEMLOCK limits.Device type : Removable CD-ROM
Version : 0
Response Format: 2
Capabilities :
Vendor_info : 'HL-DT-ST'
Identification : 'DVDRAM GSA-4163B'
Revision : 'A103'
Device seems to be: Generic mmc2 DVD-R/DVD-RW.
Using generic SCSI-3/mmc DVD-R(W) driver (mmc_mdvd).
Driver flags : SWABAUDIO BURNFREE
Supported modes: PACKET SAO
Speed set to 5540 KB/s
Starting to write CD/DVD at speed 4.0 in real unknown mode for single session.
Last chance to quit, starting real write in 0 seconds. Operation starts.
Track 01: Total bytes read/written: 4613734400/4613734400 (2252800 sectors).
So, it wrote to the disc, and seemed successful. Yet, in trying to mount it and read it, I get the following:
Code:
debian:/home/mark# mount cdrom
mount: block device /dev/hdc is write-protected, mounting read-only
mount: wrong fs type, bad option, bad superblock on /dev/hdc,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so
I took its advice:
Code:
debian:/home/mark# dmesg | tail
[14885.392288] end_request: I/O error, dev fd0, sector 0
[14885.416282] end_request: I/O error, dev fd0, sector 0
[14921.757385] UDF-fs: No VRS found
[14921.906945] ISOFS: Unable to identify CD-ROM format.
[15007.839973] UDF-fs: No VRS found
[15008.201252] ISOFS: Unable to identify CD-ROM format.
[15085.573359] UDF-fs: No VRS found
[15085.928090] ISOFS: Unable to identify CD-ROM format.
[15624.036563] UDF-fs: No VRS found
[15624.391161] ISOFS: Unable to identify CD-ROM format.
Is this normal? Am I not supposed to be able to mount it?
Last edited by mark_alfred; 10-27-2009 at 04:23 PM..
Reason: to clarify what I was referring to
Attempting backup with dd command. Expected to get truncated output, but seems to be not truncating. Issued dd command with and without the notrunc parameter. In both cases output was huge - lots bigger than amount of files on root partition. Maybe that is the default on SLES10. man pages show that notrunc is an option, though don't see a trunc option.
The individual DVDs in a backup set are not file systems. They are parts of file systems. They cannot be mounted and read like a file system. Thanks for the tip about count=. Exactly how much will fit on one DVD depends on exactly which type of recordable DVD is being used.
Attempting backup with dd command. Expected to get truncated output, but seems to be not truncating. Issued dd command with and without the notrunc parameter. In both cases output was huge - lots bigger than amount of files on root partition. Maybe that is the default on SLES10. man pages show that notrunc is an option, though don't see a trunc option.
Dd will duplicate to the end of the drive. The notrunc conversion option has nothing to do with files on the drive. If you wish to copy only what is written on the drive, use rsync as described in the OP.
[quote=AwesomeMachine;1848006]This document is made to be easily skimmed. The latest addition was on 5-21-2009, 'DVD backup of hard drive partition'. This is comprehensive documentation for one of the most useful Linux/UNIX Windows commands-dd. It is a bit-stream duplicator for duplicating data. If you have a question, post it.
First Time visitors please leave a reply.
This entire thread is very misguided. What good could it possibly do, for example, to talk about copying a hard disk to three DVDs without even mentioning how big the hard disk is? What good could it do, if the user's hard drive shows up on a different device, instead of on hda3??
Why, the post does not even explain how it arrived at the 6400M size for each DVD. When writing for beginners, you simply cannot assume such things.
Nor is dd at all comparable to Norton Ghost, which does a lot more. Ghost will do differential backups, dd will not. For that matter, will Ghost do character table based translations the way dd does? Not that I have heard of. Comparing the two is misleading at best.
Finally, there is a reason people often use rsync or cpio for backups instead of dd. For some backup situtations, they really are better.
mejohnsn tho i agree that saying that dd is comparable to Norton ghost is a bit misleading it is not all in it self incorrect. dd is a very powerful tool that "can" be used to create backups but it is also very ancient. dd has been around longer then Linux and this is evident by its rather odd looking format of commands dd of=/dev/sda for example. You can pair up dd with some other programs and create a package or live distro that will rival that of anything Norton ghost could do. I have live distro on a thumb drive that I use to create images of my windows boxes that can even create a iso image that can be burned onto a disk and used as a standalone recovery method. It uses dd but it also uses a wide range of other tools.
I would suggest any newer Linux users not experience with playing with DD to leave it alone and use something rather newer to make backups but if your interested in using it, it can be a valuable tool that is almost always available on any Linux installation.
Last edited by exvor; 11-04-2009 at 09:30 PM..
Reason: because DD is not dd this may be confusing to some....
mejohnsn tho i agree that saying that dd is comparable to Norton ghost is a bit misleading it is not all in it self incorrect. DD is a very powerful tool that "can" be used to create backups but it is also very ancient. DD has been around longer then Linux and this is evident by its rather odd looking format of commands dd of=/dev/sda for example. You can pair up dd with some other programs and create a package or live distro that will rival that of anything Norton ghost could do. I have live distro on a thumb drive that I use to create images of my windows boxes that can even create a iso image that can be burned onto a disk and used as a standalone recovery method. It uses dd but it also uses a wide range of other tools.
I would suggest any newer Linux users not experience with playing with DD to leave it alone and use something rather newer to make backups but if your interested in using it, it can be a valuable tool that is almost always available on any Linux installation.
You say it is "not all in it self[sic] incorrect", but then immediately follow this assertion with a list of reasons why it IS in fact quite incorrect.
I'll try to keep this short by mentioning one crucial aspect that recurs in your list: Norton Ghost is a single application, but to get the equivalent functionality out of 'dd', you need to learn how to use other tools, such as 'tar' and combine them with 'dd'.
That alone is enough to say that yes, it is in fact quite incorrect, because the two tools, 'dd' and "Norton Ghost" are essentially different.
Finally, the command is 'dd', NOT 'DD'. Unix command line shells are case sensitive, there is no such command as 'DD'. Referring to 'dd' as 'DD' is NOT helping anyone.
You say it is "not all in it self[sic] incorrect", but then immediately follow this assertion with a list of reasons why it IS in fact quite incorrect.
I'll try to keep this short by mentioning one crucial aspect that recurs in your list: Norton Ghost is a single application, but to get the equivalent functionality out of 'dd', you need to learn how to use other tools, such as 'tar' and combine them with 'dd'.
That alone is enough to say that yes, it is in fact quite incorrect, because the two tools, 'dd' and "Norton Ghost" are essentially different.
Finally, the command is 'dd', NOT 'DD'. Unix command line shells are case sensitive, there is no such command as 'DD'. Referring to 'dd' as 'DD' is NOT helping anyone.
Norton ghost was created to make images of peoples hard disks. dd was created to make backup tape images of peoples hard disks in this aspect they are similar. However since dd was created probably before I was born it does not have the same functionalism as Norton ghost and as such you need additional software to get the same functionality as Norton ghost. I could write a compare and contrast essay but that would be unnecessary.
One is free and included in Linux
the other is not.
If people want a backup solution this is just one of the many available options. I am also not the OP and don't feel any sort of need to defend his words and I would agree that they need some clarification.
ill aslo agree with AwesomeMachine, dd can save a lot of money, and it also teaches people about other options out there. the IT staff i was part of, before i got there, they were all about getting norton ghost, but they couldnt get the funding to purchase the enterprise edition. so i showed them the power of dd and tar, now they are using linux themselves just for everyday use. just gotta show people that linux isnt a archaic language for nerds, its a lot of point and click for those transitioning, and CLI power for those thirsting to harness its true power.
I don't like Symantec & what they seem to do to good software after they buy it. I also have no use for bought s/w, not for myself. But, it a production environment, licensing isn't the only cost a good IT mgr. needs to consider; what about technician hours saved by ease of use? Ghost may lose there too, but I wouldn't bet on it w/o doing some comparisons.
Price is not the right comparison between dd & Ghost
Absolutely true. Thank you for pointing this out. Comparing based on price alone is all too easy a trap to fall into. Especially for those of us who, being involved in Linux or Open Source, already have a prejudice in favor of free software. This prejudice often fools us into ignoring some very good software.
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Notrunc
