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On Fri, 24 Aug 2018 04:32:23 -0400, Philip Webb wrote: |
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> I want to make a copy of a partition which I can use to replace it, |
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> if some catastrophe damages the partition or wipes it out ; |
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> it needs to be byte-byte identical, incl all permissions. |
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> |
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> Can I use 'dd' ? -- eg 'dd if=/mnt/xxx of=/mnt/yyy', |
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> where the partition has been mounted at /mnt/xxx |
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> & a USB stick has been mounted at /mnt/yyy . Will that do the job ? |
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It will, provided the USB stick is large enough. |
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> There seems also to be an issue re 'bs=<some number of bytes>' : |
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> what size is best ? i plan to use USB 3.0 for quicker copying. |
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I usually use 4M but anything over 1M gives similar results. These days |
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I use dcfldd rather than dd and it gives a nice progress display and |
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also works out the block size for itself. |
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> Does it matter how the USB stick is formatted ? |
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> Can I use a raw stick with the usual default VFAT formatting ? |
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> Might it be better to replace that with a Linux FS, eg Ext2 ? |
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It doesn't matter how the stick *was* formatted because you are |
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overwriting it when you dd. The resulting stick won't even have a |
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partition table. Alternatively, format the stick and dd to a file on the |
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stick. |
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Bear in mind that dd copies the whole partition, including the bits (and |
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bytes) not currently in use by the filesystem, so it is inefficient in |
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space terms. If you just want a backup of the contents of the partition, |
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would tar not suffice? |
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-- |
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Neil Bothwick |
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If Yoda so strong in force is, why words in right order he cannot put? |
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