FreeBSD GPT

                                         Toores. Ehk seda pala võib täiendada.

GPT on MBR piirangutest vaba, näiteks ei piira GPT partitsioonide arvu (MBR ei toeta üle nelja partitsiooni) ja lubab kasutada kuni 9.4 ZB suurust ketast.

In computer hardware, GUID Partition Table (GPT) is a standard for the layout of the partition table on a physical hard disk. Although it forms a part of the Extensible Firmware Interface (EFI) standard (Intel's proposed replacement for the PC BIOS), it is also used on some BIOS systems because of the limitations of MBR partition tables, which restrict a disk partition's size to a maximum of 2.19 TB (2.19 × 1012 bytes) or 2 TiB−512 bytes (2,199,023,255,040 bytes or 4,294,967,295 (232−1) sectors × 512 (29) bytes per sector).[1] GPT allows for a maximum disk and partition size of 9.4 ZB

Kuidas installida FreeBSD 6.5TB suurusele kettale kasutades GPT partisioneerimist. Tavaline sysinstall ja fdisk kahjuks ei suuda meid siin aidata. MBRil on kaheterabaidine piirang. Näide on kirjutatud pidades silmas FreeBSD versioon 7.x ja vanemaid ning probleem võib laheneda uues FreeBSD 9/10 versioonis juba iseenesest

gpt is deprecated in freebsd 8.x ... use gpart

Esiteks boodime üles masina mingilt teiselt BSD kettalt. Meil on sihtkohaks oleva ketta tähiseks edaspidi da0

testikas# gpart show
=>        63  4883781105  ad6  MBR  (2.3T)
          63   588813809    1  freebsd  [active]  (281G)
   588813872  4294967296       - free -  (2.0T)

First, we need to remove any existing GPT partition info from the disk – ignore the ‘invalid argument’ message if you get it at this stage:

gpart destroy ad6

Siis initsialiseerime ketta

# gpart create -s GPT ad6

Tekitame partitsioonid

/
/usr
/var
swap

# gpart add -s 128 -t freebsd-boot ad6
# gpart add -s 4G -t freebsd-swap -l swap ad6
# gpart add -s 10G -t freebsd-ufs -l root ad6
# gpart add -s 15G -t freebsd-ufs -l usr ad6
# gpart add -s 25G -t freebsd-ufs -l var ad6

Muudame ketta bootivaks

# gpart bootcode -b /boot/pmbr -p /boot/gptboot -i 1 ad6

Vaatame tulemust

# gpart show
=>        34  4883781101  ad6  GPT  (2.3T)
          34         128    1  freebsd-boot  (64K)
         162     8388608    2  freebsd-swap  (4.0G)
     8388770    20971520    3  freebsd-ufs  (10G)
    29360290    31457280    4  freebsd-ufs  (15G)
    60817570    52428800    5  freebsd-ufs  (25G)
   113246370  4770534765       - free -  (2.2T)

testikas# ls /dev/ | grep ad6
ad6
ad6p1
ad6p2
ad6p3
ad6p4
ad6p5

loome neile failisüsteemid

newfs -nL root /dev/ad6p3
newfs -nL usr /dev/ad6p4
newfs -nL var /dev/ad6p5

Loome mountpoindid ja seejärel ühendame kettad nendekülge

# mount /dev/ad6p3 /mnt/root/
# mount /dev/ad6p4 /mnt/usr/
# mount /dev/ad6p5 /mnt/var/

Kõvaketas kust bootisime on /dev/ad4s1a nii ,et dumbime sealt nüüd kõik vajalikud failid ümber värsketele partitsioonidele

cd /mnt/root
dump -0Lauf - /dev/ad6s1a | restore -rf -
cd /mnt/usr
dump -0Lauf - /dev/ad6s1d | restore -rf -
cd /mnt/var
dump -0Lauf - /dev/ad6s1e | restore -rf -

Muudame ketta startivaks

freebsd-boot A FreeBSD partition dedicated to bootstrap code.

It holds bootecode, same way as MBR {as I understand}

I think it's x86 (bios or maybe even hardware) limitation.

The "old" fdisk/bsdlabel style uses /boot/mbr for the MBR and /boot/boot? for the slice. On GPT it usually is /boot/pmbr and /boot/gptboot for the bootcode partition. So, there is no need for a bootcode partition when using plain old MBR partitions/slices.

Set partition active (Optional)

Some BIOSes might require setting a Slice active. Here we set partition 1 (the Windows Partiton) as the active partition.

Fixit# gpart set -a active -i 1 ad0

Partitsiooni kustutamiseks

gpart delete -i3 ad0

And configure your timezone:

tzsetup

And setup a dummy aliases file for sendmail to keep it quiet

cd /etc/mail
make aliases

We now add our UFS and swap devices to the /etc/fstab file as follows:

echo ‘/dev/gpt/boot / ufs rw 0 0′ > /mnt/etc/fstab
echo ‘/dev/gpt/data /data ufs rw 1 1′ >> /mnt/etc/fstab
echo ‘/dev/gpt/swap none swap sw 0 0′ >> /mnt/etc/fstab

Vajalik on teha veel uus fstab /mnt/root/etc alla

/dev/ad6p4              none            swap    sw              0       0
/dev/ad6p1              /               ufs     rw              1       1
/dev/ad6p2              /usr            ufs     rw              2       2
/dev/ad6p3              /var            ufs     rw              2       2

Ja võime üritada masinat startida

Lingid

FreeBSD dumpimisest backupi eesmärgil leiab juttu

• http://blog.stardothosting.com/2010/04/14/freebsd-backup-live-filesystem-and-remotely-migrate/

• http://wiki.freebsd.org/ZFSOnRootWithZFSboot

• http://www.freebsd.org/projects/bigdisk/index.html lisalugemiseks