On Tue, 18 Jun 2013 20:48:20 +0200, Istvan Gabor wrote: > 2013. június 18. 19:49 napon Michael Sierchio <ku...@tenebras.com> írta: > > > On Tue, Jun 18, 2013 at 10:44 AM, Istvan Gabor <suseuse...@lajt.hu> wrote: > > > ... > > > How can I do this in FreeBSD? > > > Can I have slices with only one partition occupying the whole slice? > > > > > > Can I do something like the following: > > > > > > /dev/ad0s1a / > > > /dev/ad0s2e /home > > > /dev/ad0s3e /usr/local > > > /dev/ad0s5b swap > > > /dev/ad0s6e /home/user1 > > > /dev/ad0s7e /home/user2 > > > etc. > > > > > > where the partitions (a, e, b) occupy the whole slice where they reside > > > on? > > Thanks, but I don't understand your answer.
First I'd like to point you at the excellent documentation provided by FreeBSD: http://www.freebsd.org/doc/handbook/disks-adding.html http://www.freebsd.org/doc/en/books/handbook/geom-glabel.html http://www.freebsd.org/doc/handbook/bsdinstall-partitioning.html Also read Warren Block's article about the tools used in the "old" and "new" way of preparing a disk for use: http://www.wonkity.com/~wblock/docs/html/disksetup.html Regarding terminology, just if it hasn't been clear already: In UNIX terminology, a slice is what DOS and therefor "Windows" refers to as a "DOS primary partition". It is designated a number. It can be subdivided in partitions which are designated a letter. A partition carries a file system, a slice carries partitions, and finally a device carries slices. (The slicing can also be omitted, this is called "dedicated"). Examples: ad0 = the 1st disk ad0s1 = the 1st slice ad0s1a = the 1st partition of the 1st slice ... ad0s1h = the 8th partition of the 1st slice And the dedicated approach: ad0a = the 1st partition "directly" created on the 1st disk The letters have a specific meaning: 'a' is a bootable partition. 'c' is "the whole thing" (being "the whole slice" or "the whole disk"), 'b' is reserved for a swap partition, and "user-defined partitions" go from 'd' to 'h'. As I mentioned, there is a "new" and an "old" way of partitioning. What I've discussed so far is called "MBR partitioning", it's the "old" way. The "new" way, "GPT partitioning", does not use the idea of slices and partitions anymore. Instead partitions are enumerated and created "directly". Example: ad0 = the 1st disk ad0p1 = the 1st partition ... ad0p15 = the 15th partition Of course, different tools are involved here, as you can see in the documentation links provided above. > I am puzzled a little bit. My understanding based on the FreeBSD handbook is > that > slices in FreeBSD are the partitions in linux. So far correct, with an exception: A slice does _not_ carry a file system, whereas in DOS terminology, reflected in Linux, the file system is created in a DOS-like manner. Example: /dev/sda1 = 1st disk 1st DOS partition (slice) _with_ file system /dev/ad0s1 = the same, but no file system here /dev/ad0s1a = 1st partition on that slice _with_ file system > And that on one slice (linux partition) > FreeBSD has (or can have?) several partitions. Correct. > These are labeled as letters: a for root > partition, b for swap, c for the whole slice, and e for a regular non-root > partition. Correct as well. > Are you saying that one can use/mount a whole slice without adding partitions > to it? > For example /dev/ada0s1 could be the root partition? No. You _need_ to create a partition, read: "at least one partition". That partition can cover the whole slice (or device, as mentioned above), and it will be designated 'c', but that letter is omitted (I think since FreeBSD 5). Example: Let's assume you have created the /dev/ada0s1 slice already. Now you do: # newfs /dev/ada0s1 and you get a file system on the /dev/ada0s1c partition (which is created "implicitely" by newfs. You can now mount it: # mount -t ufs /dev/ada0s1 /mnt But remember: That is the 'c' partition! Similar approach for data disks (where you want to dedicate the whole disk to data use, not booting or anything else): # newfs /dev/da0 # mount -t ufs /dev/da0 /mnt Again, /dev/da0c is the device you're operating on (which carries the file system). > Do you mean putting all partitions on one big slice? With traditional partitioning, you can only use up to 'h' partitions (with exceptions). If you need more than those 8, use GPT instead. If you _must_ use MBR partitioning, you can have up to 4 slices on a disk, giving you (with exceptions) 4 x 8 = 32 partitions for FreeBSD on one disk. > I would like to be able to mount different partitions independently from > other OS, > eg. from linux. That can be problematic because Linux doesn't seem to fully support UFS file systems and BSD partitioning... If interoperability is your goal, then you should probably use "exchange partitions" with a file system that is better supported on FreeBSD (than using FreeBSD and hoping for greater-than-zero support on Linux). Check if Linux supports GPT properly. It's much easier to deal with GPT than with the limitations of MBR partitioning (which only allows up to 4 "primary DOS partitions". > As far as I know linux cannot mount FreeBSD partitions, only the > whole slice. You cannot mount a slice because it doesn't carry a file system. You can only mount "things" that carry a file system, which in UNIX terminology is a partition, either embedded in a slice, or "directly" on the disk. > If one slice has several partitions, one single partition can > not be mounted from linux. The opposite should be true. You should be able to address each partition (each one carrying a file system) independently. What you're planning is a bit complicated due to different understanding and support on Linux (while FreeBSD can access both file systems in "DOS primary partitions" and "logical devices inside DOS extended partitions". With the "fuse" and "e2fsprogs" ports you'll have sufficient access to Linux file systems beyond ext2fs. :-) -- 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"
