Re: re-write is this booting info correct?
On 12/28/09, Fbsd1 fb...@a1poweruser.com wrote: How is this rewrite correct? [...] corrupted by a virus. Microsoft/Windows provides no native method of selecting which partition to boot from in a multiple partition allocation. Windows NT and XP both use a built-in boot loader that can be used to select the boot partition. You can use it to dual-boot Windows and FreeBSD, or multiple versions of Windows (or both). There is a FreeBSD FAQ that explains how to configure it at (http://www.freebsd.org/doc/en/books/faq/disks.html#NT-BOOTLOADER). Basically, you edit the c:\boot.ini file and do a bit of other magic. In Vista and Windows 7 it changed to some new method that can still boot your choice of partitions, but the native configuration tool provided can only configure it to boot different versions of Windows. To configure it to boot FreeBSD you need a third-party tool (EasyBCD is popular). -- -- Bob Johnson ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: re-write is this booting info correct?
On Wed, 30 Dec 2009, Polytropon wrote: On Tue, 29 Dec 2009 16:29:56 +1100 (EST), Ian Smith smi...@nimnet.asn.au wrote: In freebsd-questions Digest, Vol 291, Issue 3, Message: 1 On Mon, 28 Dec 2009 21:04:57 +0800 Fbsd1 fb...@a1poweruser.com wrote: [..] All of these, at least from DOS 3 (c. '86?) use the same MBR setup, a maximum of 4 Primary Partitions, one (and only one) of which may be an Extended DOS Partition, containing as many Logical Drives as you like; they're formed as a linked list, though I never used past Drive J: with OS/2 (HPFS). (I'm using caps here to refer to the DOS nomenclature) The number is de-facto limited to 26 maximum for ALL drive letters - keyword is LETTER: A up to Z. A: and B: are reserved for floppy disk drives, C: is the booting partition (usually a primary DOS partition), D: up to Z: can be: - other primary partitions - optical drives - fake drives refering to directories (SUBST command) - external drives (INTERLNK / INTERSVR commands) The order of the drives is somewhat arbitrary, so you can't always predict drive letter behaviour. All true. Plus perhaps virtual drives provided by a Domain Controller (eg Samba) pointing to various network resources users can access. In all of these, you can't access more than one Primary Partition from any DOS-based OS; if you wish to have drives D:, E:, F: (etc) then these _must_ be in the single Extended Partition - so your statement above is not correct in that respect. I'm not sure about this. It's long time ago, so my brain isn't up to date anymore. :-) When I try to remember, I have the idea in mind that it WAS possible to partition a drive with primary partitions (max. 4). Oh you can partition it that way, but DOSes can only see one Primary Partition (PP) at a time, the Active one, on any one disk; eg you could have say DOS 6 and Win2k in separate PPs; booting either would call that one its Drive C: and any other PPs are then not visible to that OS. FreeBSD of course can mount any of the Primary or Extended Partitions as slices, as can Linux AFAIK, so this is really just a DOS/win limitation, rather than being any consequence of the MBR-based system itself. I'll check this - and I actually CAN, because I still have a DOS machine (6.22) running well; it's mostly used for programming mobile radios and for disk operations in a museal content (robotron resurrection). :-) Goodo :) I think my ancient OS/2 tower is past booting these days. I've since dusted off (which took a while :) my User's Guide to OS/2 Warp, which has very detailed info on all this. I was talking before about single-disk systems, as was fbsd1. Strange things happen to what any DOS-based OS sees if there are also Primary Partitions on HD#2 .. DOS(etc) sees the PP marked active on HD#1 as C:, always, and DOS 3-6 at least, and I suspect DOS 7 (win9x through XP) can only boot from HD #1. Further, DOS = 3.3 required that PP to be within the first 32MB, and all to 6.x need the bootable PP to be within the first 1024 cylinders. However, DOS allocates any active PP on the second disk as Drive D:, so even if there is an Extended Partition on HD #1, its Drive Letters will be allocated AFTER the D: drive on HD#2, as first E:, F: etc on HD#1 then any more on HD#2 as G: etc. This used to provide much 'fun' for folks later adding another HD who had hardcoded links to other drives. Partition Magic used to understand (and display) all these intricacies, and gparted and friends likely do also. An alternate method is to allocate an extended dos partition and then sub-divide it into logical dos drives lettered C, D, E, F. One of these Not limited to F: as above (adding the DOS colon as Polytropon suggests) My suggestion comes from documentation where C: is preferred to C (in context of drive letters), like The C: drive is the booting drive, or On floppy A: you'll find no files. Sure; when in Rome speak Latin, as it were. OK, Italian these days :) I'm not sure about NT, but certainly DOS 3 to 7 cannot boot from other than drive C: - though DOS Drive C: need not be the first physical disk partition, indeed there can be several, though only the first one marked Active is called C: by DOS on any one boot. DOS doesn't provide a native means for boot selection, so this statement appears to be correct in relation to my memories. I'm not sure if the DOSes that can multiboot (NT, W2k, XP) can do so from another PP on HD#1 or not; certainly they have to start from C: Microsoft/Windows partition and the FreeBSD slice is where the operating system software is installed. Microsoft/Windows operating system creates default folders that share the space in the partition. The FreeBSD It's not clear what you mean here by 'folders that share the space'? It seems to refer
Re: re-write is this booting info correct?
On Tue, 29 Dec 2009 09:24:40 +0800, Fbsd1 fb...@a1poweruser.com wrote: I have the win98 fdisk english version. I tested this and the fdisk program displays just the drive letter with out the :. Now on the DOS command line you do have to use the : to change to different drive, like in to change to A: drive. Yes, the fdisk program acts that way. Adding : after the drive letter (as a capital letter) is a thing you usually see in any documentation, like this erases you C: drive or check floppy in A: and B: to make sure they are present. The correct word as displayed in the fdisk program is 'logical dos drives' just the way i have it. Okay, then Laufwerk and drive are corresponding correctly. Then it's a logical drive inside an extended DOS partition. I will remember this, thanks for checking! back in win3.1 days a 20MG hard drive was the largest made at the time. I'm _sure_ it was a 20MB hard disk, maybe just a typo? :-) And for the rewrite: The Microsoft/Windows fdisk program is used to allocate partitions on the hard drive. This program allocated two types of partitions “primary dos partition” and “extended dos partition”. DOS means “disk operating system” which was the precursor to the Microsoft/Windows desktop GUI “graphical user interface” first appearing in Win 3.1. You should have DOS in caps always, as in primary DOS partition. An alternate method is to allocate an “extended dos partition” and then sub-divide it into logical dos drives lettered C, D, E, F. And it is possible to have a bootable system without a primary DOS partition? I hardly can imagine that - but don't bet on my opinion, I've NEVER used any Windows, so I'm honestly just guessing. A typical multi-drive setting would contain a primary DOS partition C:, and an extended DOS partition containing the logical drives D:, E: and F: (for your 4-drive example). The FreeBSD ‘disk label’ program is used to sub-divide the slice into smaller chunks called partitions. The program's name is disklabel or bsdlabel respectively. This hard drive 512-byte MBR is where all the limitations are. Due to its size the MBR partition table is limited to 4 entries. This means no matter how large your hard drive is (20MG or 200GB) you can only sub-divide it into a maximum 4 slices/partitions. I'm sure you wanted to say 20MB - megaBytes. :-) The FreeBSD fdisk program has option to write a simple boot menu program to the MBR. Its called the FreeBSD boot manager. The program boot0cfg does this. -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: re-write is this booting info correct?
On Tue, 29 Dec 2009 16:29:56 +1100 (EST), Ian Smith smi...@nimnet.asn.au wrote: In freebsd-questions Digest, Vol 291, Issue 3, Message: 1 On Mon, 28 Dec 2009 21:04:57 +0800 Fbsd1 fb...@a1poweruser.com wrote: Content-Type: text/plain; charset=windows-1252; format=flowed First up, you'd be better off using a non-Windows charset here, as they use weird characters just for ordinary things like quotes, as below. Good and helpful advice. Even apostrophes get messed up. All of these, at least from DOS 3 (c. '86?) use the same MBR setup, a maximum of 4 Primary Partitions, one (and only one) of which may be an Extended DOS Partition, containing as many Logical Drives as you like; they're formed as a linked list, though I never used past Drive J: with OS/2 (HPFS). (I'm using caps here to refer to the DOS nomenclature) The number is de-facto limited to 26 maximum for ALL drive letters - keyword is LETTER: A up to Z. A: and B: are reserved for floppy disk drives, C: is the booting partition (usually a primary DOS partition), D: up to Z: can be: - other primary partitions - optical drives - fake drives refering to directories (SUBST command) - external drives (INTERLNK / INTERSVR commands) The order of the drives is somewhat arbitrary, so you can't always predict drive letter behaviour. In all of these, you can't access more than one Primary Partition from any DOS-based OS; if you wish to have drives D:, E:, F: (etc) then these _must_ be in the single Extended Partition - so your statement above is not correct in that respect. I'm not sure about this. It's long time ago, so my brain isn't up to date anymore. :-) When I try to remember, I have the idea in mind that it WAS possible to partition a drive with primary partitions (max. 4). I'll check this - and I actually CAN, because I still have a DOS machine (6.22) running well; it's mostly used for programming mobile radios and for disk operations in a museal content (robotron resurrection). :-) An alternate method is to allocate an extended dos partition and then sub-divide it into logical dos drives lettered C, D, E, F. One of these Not limited to F: as above (adding the DOS colon as Polytropon suggests) My suggestion comes from documentation where C: is preferred to C (in context of drive letters), like The C: drive is the booting drive, or On floppy A: you'll find no files. I'm not sure about NT, but certainly DOS 3 to 7 cannot boot from other than drive C: - though DOS Drive C: need not be the first physical disk partition, indeed there can be several, though only the first one marked Active is called C: by DOS on any one boot. DOS doesn't provide a native means for boot selection, so this statement appears to be correct in relation to my memories. Microsoft/Windows partition and the FreeBSD slice is where the operating system software is installed. Microsoft/Windows operating system creates default folders that share the space in the partition. The FreeBSD It's not clear what you mean here by 'folders that share the space'? It seems to refer to the fact that the functional separation in Windows is done through directories (folders), instead of partitions. -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
re-write is this booting info correct?
How is this rewrite correct? Users with Microsoft/Windows knowledge of how a hard drive is configured may have a terminology issue with FreeBSD. Microsoft/Windows and FreeBSD use the word partition to mean different (but related) things. The Microsoft/Windows fdisk program is used to allocate partitions on the hard drive. This program allocated two types of partitions “primary dos partition” and “extended dos partition”. A single “primary dos partition” occupying all the space on the hard drive would be assigned drive letter C. You can also sub-divide the hard drive into multiple “primary dos partition” each one being assigned a drive letter C, D, E, F, An alternate method is to allocate an “extended dos partition” and then sub-divide it into logical dos drives lettered C, D, E, F. One of these “primary dos partitions” or one of the logical dos drives in the “extended dos partition” must be set as the active partition to boot from. In a multiple partition allocation only one partition can be marked as bootable at one time. Typically legacy Microsoft/Windows Win3.1, Win95, Win98, WinMe, and Win2000 defaulted to a single “primary dos partition”. Starting with XP, PC manufactures started to provide support for their PC’s operating system by having a second “primary dos partition” where the original factory version of the system was hidden and used to restore the C drive back to the factory version when corrupted by a virus. Microsoft/Windows provides no native method of selecting which partition to boot from in a multiple partition allocation. FreeBSD’s fdisk program allocates disk space into slices. A FreeBSD slice is the same thing as a Microsoft/Windows “primary dos partition”. FreeBSD has nothing akin to an “extended dos partition”. The Microsoft/Windows partition and the FreeBSD slice is where the operating system software is installed. Microsoft/Windows operating system creates default folders that share the space in the partition. The FreeBSD ‘disk label’ program is used to sub-divide the slice into smaller chunks called partitions. In a standard install of FreeBSD, these partitions are the default directory names used by the operating system. The motherboard standard which was created in the days before windows desktop were even though of yet and at which time Microsoft DOS (disk operating system) was the only thing available. This legacy standard has continued un-updated to this current time and contributes to the limitations imposed on booting, disk layout and selection of which allocation on the hard disk to boot from. The motherboard BIOS ROM chip at power up inquires each device (floppies, cdrom, hard drive, usb memory stick) you selected in the BIOS menu to boot from. The hard drive has a MBR (Master Boot Record) a (512 byte block) located in sector-0 of the first physical track on the hard drive. This MBR contains bootstrap code and the disk partition table created by the fdisk program. The BIOS boot code reads the MBR code and disk partition table into memory and then transfers control to it. This MBR code is responsible for parsing the partition table and finding the bootable slice/partition that is marked 'active'. The MBR code then sets up the disk-address-offset information for the bootable slice/partition, and reads 'relative sector zero' from that slice/partition, and transfers control to that one-sector block of code that contains the unique operating system code to load it into memory. This hard drive 512-byte MBR is where all the limitations are. Do to it’s size the MBR partition table is limited to 4 entries. This means no matter how large your hard drive is (20MG or 200GB) you can only sub-divide it into a maximum 4 slices/partitions. The default MBR code written by the Microsoft/Windows fdisk program is hard coded to boot the C drive. The FreeBSD fdisk program has option to write a simple boot menu program to the MBR. There are MBR boot menu programs in the FreeBSD ports collection that you can load into the MBR on the first physical cabled hard drive to scan for other bootable primary-partitions/slices on this hard drive and any other hard drives cabled to the PC. It displays a menu giving you the option to choose which one you want to boot from. This gives you the ability to have more that one operating system installed on your PC at one time. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: re-write is this booting info correct?
On Mon, 28 Dec 2009 21:04:57 +0800, Fbsd1 fb...@a1poweruser.com wrote: The Microsoft/Windows fdisk program is used to allocate partitions on the hard drive. This program allocated two types of partitions “primary dos partition” and “extended dos partition”. Just a formal addition: primary DOS partition - DOS stands for Disk Operating System, it's an abbreviation. You're stating this later on, but you should do it at its first occurance. A single “primary dos partition” occupying all the space on the hard drive would be assigned drive letter C. The drive letters used seem to include the : as a part, so it would be C: instead of plain C. An alternate method is to allocate an “extended dos partition” and then sub-divide it into logical dos drives lettered C, D, E, F. I think the term is logical volume inside an extended DOS partition; I'm not very familiar with their english names, but that would correspond to the correct german name (found in german versions of DOS); the term is volume or drive. I've got no english DOS documentation here, so I can't check for the correct term. German: Primäre DOS-Partition and Logisches Laufwerk in einer erweiterten DOS-Partition, and Laufwerk means drive, but I think I recall that DOS uses volume for this... One of these “primary dos partitions” or one of the logical dos drives in the “extended dos partition” must be set as the active partition to boot from. I'm not sure you can actually boot from a logical volume inside an extended DOS partition... as far as I remember, booting can only take place from a primary DOS partition. FreeBSD’s fdisk program allocates disk space into slices. A FreeBSD slice is the same thing as a Microsoft/Windows “primary dos partition”. FreeBSD has nothing akin to an “extended dos partition”. It quite has - its slices (which are subdivided just as the extended DOS partitions are, so its partitions are like - but not the same as - the logical volumes inside a DOS extended partition). The Microsoft/Windows partition and the FreeBSD slice is where the operating system software is installed. No. The software is installed on the partitions inside a slice, or, to be more exact, in the file system that the partition holds. There can be of course one partition coviering the whole slice, so partition(s) would be a valid term. The FreeBSD ‘disk label’ program is used to sub-divide the slice into smaller chunks called partitions. In a standard install of FreeBSD, these partitions are the default directory names used by the operating system. Not are - they _refer_ to them (or are refered to by then), e. g. the default directory name / is the root directory, but /dev/ad0s1a is the partition; /usr is the directory for { UNIX system resources | user binaries and libraries }, but /dev/ad0s1g is (maybe) the partition that holds this data. In settings where one partition convers the whole slice, there are no further mountpoints for the divisions of functional parts of the system. The motherboard standard which was created in the days before windows desktop were even though of yet and at which time Microsoft DOS (disk operating system) was the only thing available. Sure. :-) This hard drive 512-byte MBR is where all the limitations are. Do to it’s size the MBR partition table is limited to 4 entries. Due to its size... This means no matter how large your hard drive is (20MG or 200GB) you can only sub-divide it into a maximum 4 slices/partitions. 20MB. But I'd like to have a 20 machine gun hard disk, too. :-) The default MBR code written by the Microsoft/Windows fdisk program is hard coded to boot the C drive. The FreeBSD fdisk program has option to write a simple boot menu program to the MBR. You could add that this program is called the FreeBSD boot manager, because that's its actual name. Everything else seems to be correct to me, as well as written in an appealing way, and technically understandable. -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: re-write is this booting info correct?
Polytropon wrote: On Mon, 28 Dec 2009 21:04:57 +0800, Fbsd1 fb...@a1poweruser.com wrote: The Microsoft/Windows fdisk program is used to allocate partitions on the hard drive. This program allocated two types of partitions “primary dos partition” and “extended dos partition”. Just a formal addition: primary DOS partition - DOS stands for Disk Operating System, it's an abbreviation. You're stating this later on, but you should do it at its first occurance. for correctness i agree. A single “primary dos partition” occupying all the space on the hard drive would be assigned drive letter C. The drive letters used seem to include the : as a part, so it would be C: instead of plain C. I have the win98 fdisk english version. I tested this and the fdisk program displays just the drive letter with out the :. Now on the DOS command line you do have to use the : to change to different drive, like in to change to A: drive. An alternate method is to allocate an “extended dos partition” and then sub-divide it into logical dos drives lettered C, D, E, F. I think the term is logical volume inside an extended DOS partition; I'm not very familiar with their english names, but that would correspond to the correct german name (found in german versions of DOS); the term is volume or drive. I've got no english DOS documentation here, so I can't check for the correct term. German: Primäre DOS-Partition and Logisches Laufwerk in einer erweiterten DOS-Partition, and Laufwerk means drive, but I think I recall that DOS uses volume for this... The correct word as displayed in the fdisk program is 'logical dos drives' just the way i have it. One of these “primary dos partitions” or one of the logical dos drives in the “extended dos partition” must be set as the active partition to boot from. I'm not sure you can actually boot from a logical volume inside an extended DOS partition... as far as I remember, booting can only take place from a primary DOS partition. I tested this and can confirm you can boot from a logical drive inside an extended DOS partition. Just have to set the active flag first. FreeBSD’s fdisk program allocates disk space into slices. A FreeBSD slice is the same thing as a Microsoft/Windows “primary dos partition”. FreeBSD has nothing akin to an “extended dos partition”. It quite has - its slices (which are subdivided just as the extended DOS partitions are, so its partitions are like - but not the same as - the logical volumes inside a DOS extended partition). The Microsoft/Windows partition and the FreeBSD slice is where the operating system software is installed. No. The software is installed on the partitions inside a slice, or, to be more exact, in the file system that the partition holds. There can be of course one partition coviering the whole slice, so partition(s) would be a valid term. The FreeBSD ‘disk label’ program is used to sub-divide the slice into smaller chunks called partitions. In a standard install of FreeBSD, these partitions are the default directory names used by the operating system. Not are - they _refer_ to them (or are refered to by then), e. g. the default directory name / is the root directory, but /dev/ad0s1a is the partition; /usr is the directory for { UNIX system resources | user binaries and libraries }, but /dev/ad0s1g is (maybe) the partition that holds this data. In settings where one partition convers the whole slice, there are no further mountpoints for the divisions of functional parts of the system. The motherboard standard which was created in the days before windows desktop were even though of yet and at which time Microsoft DOS (disk operating system) was the only thing available. Sure. :-) This hard drive 512-byte MBR is where all the limitations are. Do to it’s size the MBR partition table is limited to 4 entries. Due to its size... good catch. This means no matter how large your hard drive is (20MG or 200GB) you can only sub-divide it into a maximum 4 slices/partitions. 20MB. But I'd like to have a 20 machine gun hard disk, too. :-) back in win3.1 days a 20MG hard drive was the largest made at the time. The default MBR code written by the Microsoft/Windows fdisk program is hard coded to boot the C drive. The FreeBSD fdisk program has option to write a simple boot menu program to the MBR. You could add that this program is called the FreeBSD boot manager, because that's its actual name. Everything else seems to be correct to me, as well as written in an appealing way, and technically understandable. I am adding this verbiage to my FreeBSD installer Guide for release 8.0 which will be available to the public 1/1/2010 at http://www.a1poweruser.com/ following is the corrected version incorporating your ideas. Users with Microsoft/Windows knowledge of how a hard drive is configured may have a terminology issue with FreeBSD. Microsoft/Windows and FreeBSD
Re: re-write is this booting info correct?
In freebsd-questions Digest, Vol 291, Issue 3, Message: 1 On Mon, 28 Dec 2009 21:04:57 +0800 Fbsd1 fb...@a1poweruser.com wrote: Content-Type: text/plain; charset=windows-1252; format=flowed First up, you'd be better off using a non-Windows charset here, as they use weird characters just for ordinary things like quotes, as below. How is this rewrite correct? Users with Microsoft/Windows knowledge of how a hard drive is configured may have a terminology issue with FreeBSD. Microsoft/Windows and FreeBSD use the word partition to mean different (but related) things. The Microsoft/Windows fdisk program is used to allocate partitions on the hard drive. This program allocated two types of partitions primary dos partition and extended dos partition. A single primary dos partition occupying all the space on the hard drive would be assigned drive letter C. You can also sub-divide the hard drive into multiple primary dos partition each one being assigned a drive letter C, D, E, F, Not exactly, and I assume you're hoping to be exact. Disclaimer: I know nothing about Vista or its successor Windows 7, nor do I care to, but I've used many DOS versions - 3, 5, 6 (base of Win 3.1), 7 (under Win95 through to XP) - in both MS and IBM variants, plus IBM OS/2 v2 and v3, and have had some exposure to NT (4 and 5), the latter having been being merged into Win2k and XP to some degree, including of course its NTFS. All of these, at least from DOS 3 (c. '86?) use the same MBR setup, a maximum of 4 Primary Partitions, one (and only one) of which may be an Extended DOS Partition, containing as many Logical Drives as you like; they're formed as a linked list, though I never used past Drive J: with OS/2 (HPFS). (I'm using caps here to refer to the DOS nomenclature) In all of these, you can't access more than one Primary Partition from any DOS-based OS; if you wish to have drives D:, E:, F: (etc) then these _must_ be in the single Extended Partition - so your statement above is not correct in that respect. An alternate method is to allocate an extended dos partition and then sub-divide it into logical dos drives lettered C, D, E, F. One of these Not limited to F: as above (adding the DOS colon as Polytropon suggests) primary dos partitions or one of the logical dos drives in the extended dos partition must be set as the active partition to boot from. I don't think even XP can boot from a Logical Drive in the Extended Partition. OS/2 can be installed to and booted from a Logical Drive (though only by using the OS/2 Boot Manager or Grub ono), as can most? varieties of Linux. I'm not sure about NT, but certainly DOS 3 to 7 cannot boot from other than drive C: - though DOS Drive C: need not be the first physical disk partition, indeed there can be several, though only the first one marked Active is called C: by DOS on any one boot. In a multiple partition allocation only one partition can be marked as bootable at one time. Typically legacy Microsoft/Windows Win3.1, Win95, Win98, WinMe, and Win2000 defaulted to a single primary dos partition. Starting with XP, PC manufactures started to provide support for their PCs operating system by having a second primary dos partition where the original factory version of the system was hidden and used to restore the C drive back to the factory version when corrupted by a virus. Again, not exactly or always correct. Compaq at least were providing a 'hidden' Primary Partition as early as '98 on laptops, for a diagnostics boot (running DOS 6.2 with a mini-Win 3.1 'desktop', FWIW). And while most OEMs and computer shops were in that 'default' habit of installing a single C: partition (and many still are), that was an install choice; most people with a clue were using multiple DOS Drives, requiring use of the Extended Partition, since DOS 3. Microsoft/Windows provides no native method of selecting which partition to boot from in a multiple partition allocation. At least NT, Win2k and XP can multiboot .. W2k uses C:\boot.ini listing bootable OSes, and as I recall it's called \NTLDR.something on XP. FreeBSDs fdisk program allocates disk space into slices. A FreeBSD slice is the same thing as a Microsoft/Windows primary dos partition. FreeBSD has nothing akin to an extended dos partition. The Although FreeBSD can mount and access the multiple Logical Drives as slices 5 and up. I'm not sure if FreeBSD has any limit to the number of such slices it can access, but I've recovered multiple HPFS 'drives' that way, and you can access DOS FAT, NTFS, HPFS (requires compiling code still in the tree at 8.0-R) and Linux ext2 and ext3 filesystems. It's true that sysinstall can't access such slices, there are comments in the code suggesting it should maybe be added, though unlikely now :) Microsoft/Windows partition and the FreeBSD slice is where the
Re: is this booting info correct?
Fbsd1 wrote: [snip] The number of hard drive primary-partitions/slices is determined by the motherboard BIOS (Basic input output system), not the operating system. Standard motherboard BIOS limits hard-drives to 4 main divisions [snip] Not quite true. The only thing contained within the BIOS is an instruction to jump to sector 0 of track 0 after a successful POST. -Mike ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: is this booting info correct?
On Thu, Dec 17, 2009 at 06:49:59AM +0100, Polytropon wrote: On Thu, 17 Dec 2009 07:33:58 +0800, Fbsd1 fb...@a1poweruser.com wrote: Users with Microsoft/Windows knowledge of how a hard drive is configured may have a terminology issue with FreeBSD. Microsoft/Windows and FreeBSD use the word partition to mean different (but related) things. FreeBSD and Microsoft/Windows have primary-partitions, but they call them different things. FreeBSD calls the Microsoft/Windows primary-partition a slice. FreeBSD's slice is a DOS primary partition. FreeBSD's partition is comparable (but not equal to) a logical volume inside a DOS extended partition. The number of hard drive primary-partitions/slices is determined by the motherboard BIOS (Basic input output system), not the operating system. Standard motherboard BIOS limits hard-drives to 4 main divisions The limitation to 4 slices is due to DOS limitations that are still present for legacy in the PC sector. But, the reason they are still present is that it is in BIOS. Of course, BIOS was written with old DOS in mind. Nowdays it has nothing to do with the OS. Each of those are called primary-partitions in Microsoft/Windows terminology and slices in FreeBSD terminology. Yes. ... They are implemented very differently and are not compatible with FreeBSD. I've not had problems accessing them so far. From FreeBSD, you can access almost anything because people in the FreeBSD community have written code to do it. In FreeBSD the sub-divisions are called partitions. But only the subdivisions of a FreeBSD slice are called this way. Yup. And the OP is interested in FreeBSD. ... The first physical track of the allocated space of each primary-partition/slice has an initial sector (512 byte block) that is called the boot sector. If it contains boot up code the motherboard BIOS considers it to be bootable. Yes. No. It is the MBR that figures out if it is bootable. That is a step beyond BIOS. Each physical hard drive in the PC has it's own MBR (Master Boot Record). The MBR is located in sector-0 of the first physical track on the hard drive. The standard MBR in Microsoft/Windows and FreeBSD defaults to booting the first primary-partition/slice allocated on the first hard drive cabled to the PC. No. The MBR usually branches to the first slice it finds that has the bootable flag set. It doesn't have to be the first one on the disk. Sort of. It has its own flag saying which one to boot and FreeBSD usually sets this as the last one booted. In case of FreeBSD, feel free to read man boot which gives a good introduction to the topic. There are MBR booting programs that you can load into the MBR on the first physical cabled hard drive to scan for other bootable primary-partitions/slices on this hard drive and any other hard drives cabled to the PC. It displays a menu giving you the option to choose which one you want to boot from. This gives you the ability to have more that one operating system installed on your PC at one time. Exact. Not exactly.The BIOS goes down its list of boot devices which you can set and picks the first one it finds with an bootable MBR on it. loads that MBR and transfers control to it. Then the MBR controls the task of looking at its own slices for bootable ones loading one and transferring control to it. jerry -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: is this booting info correct?
On Thu, Dec 17, 2009 at 10:11:40AM -0500, Jerry McAllister wrote: On Thu, Dec 17, 2009 at 06:49:59AM +0100, Polytropon wrote: On Thu, 17 Dec 2009 07:33:58 +0800, Fbsd1 fb...@a1poweruser.com wrote: Users with Microsoft/Windows knowledge of how a hard drive is configured may have a terminology issue with FreeBSD. Microsoft/Windows and FreeBSD use the word partition to mean different (but related) things. FreeBSD and Microsoft/Windows have primary-partitions, but they call them different things. FreeBSD calls the Microsoft/Windows primary-partition a slice. FreeBSD's slice is a DOS primary partition. FreeBSD's partition is comparable (but not equal to) a logical volume inside a DOS extended partition. The number of hard drive primary-partitions/slices is determined by the motherboard BIOS (Basic input output system), not the operating system. Standard motherboard BIOS limits hard-drives to 4 main divisions The limitation to 4 slices is due to DOS limitations that are still present for legacy in the PC sector. But, the reason they are still present is that it is in BIOS. Of course, BIOS was written with old DOS in mind. Nowdays it has nothing to do with the OS. I may have overstated that. Even the most basic MBR (such as FreeBSD's) may be a little different from one OS to the next. The MBR chooses the slice, so it might be changeable from there. I haven't looked at that stuff in about 11 years. jerry Each of those are called primary-partitions in Microsoft/Windows terminology and slices in FreeBSD terminology. Yes. ... They are implemented very differently and are not compatible with FreeBSD. I've not had problems accessing them so far. From FreeBSD, you can access almost anything because people in the FreeBSD community have written code to do it. In FreeBSD the sub-divisions are called partitions. But only the subdivisions of a FreeBSD slice are called this way. Yup. And the OP is interested in FreeBSD. ... The first physical track of the allocated space of each primary-partition/slice has an initial sector (512 byte block) that is called the boot sector. If it contains boot up code the motherboard BIOS considers it to be bootable. Yes. No. It is the MBR that figures out if it is bootable. That is a step beyond BIOS. Each physical hard drive in the PC has it's own MBR (Master Boot Record). The MBR is located in sector-0 of the first physical track on the hard drive. The standard MBR in Microsoft/Windows and FreeBSD defaults to booting the first primary-partition/slice allocated on the first hard drive cabled to the PC. No. The MBR usually branches to the first slice it finds that has the bootable flag set. It doesn't have to be the first one on the disk. Sort of. It has its own flag saying which one to boot and FreeBSD usually sets this as the last one booted. In case of FreeBSD, feel free to read man boot which gives a good introduction to the topic. There are MBR booting programs that you can load into the MBR on the first physical cabled hard drive to scan for other bootable primary-partitions/slices on this hard drive and any other hard drives cabled to the PC. It displays a menu giving you the option to choose which one you want to boot from. This gives you the ability to have more that one operating system installed on your PC at one time. Exact. Not exactly.The BIOS goes down its list of boot devices which you can set and picks the first one it finds with an bootable MBR on it. loads that MBR and transfers control to it. Then the MBR controls the task of looking at its own slices for bootable ones loading one and transferring control to it. jerry -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
is this booting info correct?
Users with Microsoft/Windows knowledge of how a hard drive is configured may have a terminology issue with FreeBSD. Microsoft/Windows and FreeBSD use the word partition to mean different (but related) things. FreeBSD and Microsoft/Windows have primary-partitions, but they call them different things. FreeBSD calls the Microsoft/Windows primary-partition a slice. The number of hard drive primary-partitions/slices is determined by the motherboard BIOS (Basic input output system), not the operating system. Standard motherboard BIOS limits hard-drives to 4 main divisions Each of those are called primary-partitions in Microsoft/Windows terminology and slices in FreeBSD terminology. Each primary-partition/slice can be sub-divided into smaller chunks. In Microsoft/Windows, they are called extended-partitions. They are implemented very differently and are not compatible with FreeBSD. In FreeBSD the sub-divisions are called partitions. Each one of the 4 max primary-partitions/slices can be made bootable. The first physical track of the allocated space of each primary-partition/slice has an initial sector (512 byte block) that is called the boot sector. If it contains boot up code the motherboard BIOS considers it to be bootable. Each physical hard drive in the PC has it's own MBR (Master Boot Record). The MBR is located in sector-0 of the first physical track on the hard drive. The standard MBR in Microsoft/Windows and FreeBSD defaults to booting the first primary-partition/slice allocated on the first hard drive cabled to the PC. There are MBR booting programs that you can load into the MBR on the first physical cabled hard drive to scan for other bootable primary-partitions/slices on this hard drive and any other hard drives cabled to the PC. It displays a menu giving you the option to choose which one you want to boot from. This gives you the ability to have more that one operating system installed on your PC at one time. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: is this booting info correct?
On Thu, Dec 17, 2009 at 07:33:58AM +0800, Fbsd1 wrote: Everything but the last couple of paragraphs are correct. Users with Microsoft/Windows knowledge of how a hard drive is configured may have a terminology issue with FreeBSD. Microsoft/Windows and FreeBSD use the word partition to mean different (but related) things. FreeBSD and Microsoft/Windows have primary-partitions, but they call them different things. FreeBSD calls the Microsoft/Windows primary-partition a slice. The number of hard drive primary-partitions/slices is determined by the motherboard BIOS (Basic input output system), not the operating system. Standard motherboard BIOS limits hard-drives to 4 main divisions Each of those are called primary-partitions in Microsoft/Windows terminology and slices in FreeBSD terminology. Each primary-partition/slice can be sub-divided into smaller chunks. In Microsoft/Windows, they are called extended-partitions. They are implemented very differently and are not compatible with FreeBSD. In FreeBSD the sub-divisions are called partitions. Each one of the 4 max primary-partitions/slices can be made bootable. The first physical track of the allocated space of each primary-partition/slice has an initial sector (512 byte block) that is called the boot sector. If it contains boot up code the motherboard BIOS considers it to be bootable. This is the '3rd' level (phase) of the boot process. The first being the BIOS, the second being the MBR and the third being the slice boot sector. Each physical hard drive in the PC has it's own MBR (Master Boot Record). The MBR is located in sector-0 of the first physical track on the hard drive. The standard MBR in Microsoft/Windows and FreeBSD defaults to booting the first primary-partition/slice allocated on the first hard drive cabled to the PC. Each drive has a sector 0. When you install FreeBSD you can write an MBR in to that sector 0. You can also install other (third party) MBRs in to that sector. There are MBR booting programs that you can load into the MBR on the first physical cabled hard drive to scan for other bootable primary-partitions/slices on this hard drive and any other hard drives cabled to the PC. It displays a menu giving you the option to choose which one you want to boot from. This gives you the ability to have more that one operating system installed on your PC at one time. The sector isn't the MBR. The code and table that gets written to that sector is the MBR.If you don't want to boot from the drive - eg just use it for data, you can ignore that sector and not write any MBR in to it. The MBR has a little table in which is marked which slice to continue the boot with. The FreeBSD MBR (and some others) sets that to be the current slice when a boot is done. So, the last slice to be booted is always the default boot the next time. You can manually change that with fdisk(8). Some people have wanted to have a fancier MBR than can fit in a single sector. Almost all systems nowdays use that 0 sector, but then just ignore the rest of the track that it is in. So, there are several wasted sectors following the MBR. Those people have made use of that space to install a more elaborate MBR, depending on that extra space never being used for anything else - which is a pretty good bet. In fact, I don't quite understand why people don't just go ahead and define the standard so that track is specified as available for MBR. The MBR is fairly basic and conforms to a fairly tight but primative system for finding and initiating boot sectors in slices/primary partitions.Because that part is almost all the same across most systems, most MBRs can boot most OSen on PCs if they want to. MS does not seem to want to, but FreeBSD and Linux can. But, the boot sector in each slice/primary partition is unique to the OS being booted. It has a common boot flag setup and a common place to jump to to begin execution, but the rest is OS specific. Basically, the BIOS does its thing and looks for an MBR in sector 0 of the drives in its boot list. The first one it finds, it loads in and transfers control to it. The MBR does a couple checks and looks for a bootable slice and which is flagged to be the default boot. It puts up a simple boot menu allowing you to choose. If you do not respond in time, it goes with the flag setting. The MBR then reads in the first (boot) sector of the slice and transfers control to it. That sector code knows how to find what it needs to finish the boot, load the kernel, etc and start up init which gets everything else going. The process has changed in detail, but not much in concept since the beginning of computer OSen. The reaason it is called booting is that especially in the old days, when some parts of the startup were keyed in by hand, it had the feeling of the system pulling itself up by its own bootstraps - an old and popular country saying. Anyway, you
Re: is this booting info correct?
On Thu, 17 Dec 2009 07:33:58 +0800, Fbsd1 fb...@a1poweruser.com wrote: Users with Microsoft/Windows knowledge of how a hard drive is configured may have a terminology issue with FreeBSD. Microsoft/Windows and FreeBSD use the word partition to mean different (but related) things. FreeBSD and Microsoft/Windows have primary-partitions, but they call them different things. FreeBSD calls the Microsoft/Windows primary-partition a slice. FreeBSD's slice is a DOS primary partition. FreeBSD's partition is comparable (but not equal to) a logical volume inside a DOS extended partition. The number of hard drive primary-partitions/slices is determined by the motherboard BIOS (Basic input output system), not the operating system. Standard motherboard BIOS limits hard-drives to 4 main divisions The limitation to 4 slices is due to DOS limitations that are still present for legacy in the PC sector. Each of those are called primary-partitions in Microsoft/Windows terminology and slices in FreeBSD terminology. Yes. Each primary-partition/slice can be sub-divided into smaller chunks. In Microsoft/Windows, they are called extended-partitions. No. As far as I understood and listed before, a DOS primary partition cannot be subdivided. That's why the DOS extended partition has been invented which allows subdivion by the means of logical volumes. A DOS extended partition takes the place of a DOS primary partition. They are implemented very differently and are not compatible with FreeBSD. I've not had problems accessing them so far. In FreeBSD the sub-divisions are called partitions. But only the subdivisions of a FreeBSD slice are called this way. Each one of the 4 max primary-partitions/slices can be made bootable. But not all at the same time. :-) The first physical track of the allocated space of each primary-partition/slice has an initial sector (512 byte block) that is called the boot sector. If it contains boot up code the motherboard BIOS considers it to be bootable. Yes. Each physical hard drive in the PC has it's own MBR (Master Boot Record). The MBR is located in sector-0 of the first physical track on the hard drive. The standard MBR in Microsoft/Windows and FreeBSD defaults to booting the first primary-partition/slice allocated on the first hard drive cabled to the PC. No. The MBR usually branches to the first slice it finds that has the bootable flag set. It doesn't have to be the first one on the disk. In case of FreeBSD, feel free to read man boot which gives a good introduction to the topic. There are MBR booting programs that you can load into the MBR on the first physical cabled hard drive to scan for other bootable primary-partitions/slices on this hard drive and any other hard drives cabled to the PC. It displays a menu giving you the option to choose which one you want to boot from. This gives you the ability to have more that one operating system installed on your PC at one time. Exact. -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org