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Richard Fish wrote: |
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> Jarry wrote: |
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> |
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>> |
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>> Is it not possible to archive MBR too? That way I could save 5. and |
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>> 6., and to automate it with some scripts... |
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> |
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> |
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> |
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> Technically, yes, I guess you could do this. Although, I don't know if |
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> I would really recommend it. |
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> |
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> If you are using a stage 1.5 with grub, you would need to archive the |
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> first 63 blocks of the disk (technically fewer than that, but you would |
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> have to check grub-install's output to be sure of the exact count, and |
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> 63 is the safe number). This is because grub embeds the stage1.5 loader |
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> after the mbr (first block) and the start of the first partition. |
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> |
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> If you are not using the stage 1.5, or you are using lilo, then you have |
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> little choice but to reinstall the boot loader. This is because some |
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> files in /boot are block mapped into the mbr, and the restore process |
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> may have changed the layout of these files, so the block map will be |
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> incorrect. |
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> |
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> I think the safest route is to always let the system write a fresh mbr. |
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> |
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> -Richard |
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> |
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|
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It make sense but is easily bypassable using "hda1" as boot partition |
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AND it's the first on disk, with a little help from "fdisk" and "dd" |
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("##" are shell commands "#" comm.inside fdisk): |
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|
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==== hikky trikky ==== |
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##fdisk /dev/hda |
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#Command (m for help): u |
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Changing display/entry units to sectors |
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#Command (m for help): p |
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|
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Disk /dev/hda: 40.0 GB, 40027029504 bytes |
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255 heads, 63 sectors/track, 4866 cylinders, total 78177792 sectors |
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Units = sectors of 1 * 512 = 512 bytes |
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|
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Device Boot Start End Blocks Id System |
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/dev/hda1 * 63 979964 489951 83 Linux |
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#Command (m for help): q |
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|
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##dd if=/dev/hda of=MBR-boot.backup bs=512 count=489951 |
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==== hikky trikky ==== |
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|
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MBR-boot.backup now contain your MBR + the boot partition. |
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|
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now three question: |
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a) I know noone that use this backup method, is it affidable ? |
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b) What happen if it need to be restored on another disk |
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c) HOW do I restore (hint "man dd") |
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|
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Another hint: always try at least one restore after a choice of backup |
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method, the rule is "you never know" . |
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|
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cheers |
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Francesco |
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-- |
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