Ikkopjar volumi għal sistemi ta 'ħażna permezz ta' server Linux bl-użu ta 'XCOPY

Jiġri li għandek bżonn tikseb kopja sħiħa ta 'volum f'sistema waħda ta' ħażna tad-dejta (DSS), mhux stampa, klonu, iżda volum sħiħ. Iżda s-sistema tal-ħażna mhux dejjem tippermetti li dan isir internament bl-użu tal-mezzi tagħha stess. Jidher li l-unika għażla hija li tikkopja permezz tas-server, iżda f'dan il-każ il-volum kollu ta 'data se jiġi misjuq permezz tas-server innifsu, in-netwerk għas-sistema tal-ħażna u l-portijiet tal-ħażna, it-tagħbija ta' dawn il-komponenti kollha. Iżda hemm kmandi SCSI li jistgħu jippermettulek tagħmel kollox fis-sistema tal-ħażna nnifisha, u jekk is-sistema tiegħek tappoġġja VAAI minn VMware, allura huwa kważi 100% li l-kmand XCOPY (EXTENDED COPY) huwa appoġġjat, li jgħid lill-array x'u fejn tikkopja, mingħajr ma tinvolvi server tal-proċess u netwerk.

Jidher li kollox għandu jkun sempliċi, iżda ma stajt insib l-ebda skripts lesti mill-ewwel, għalhekk kelli nivvinta r-rota mill-ġdid. Intgħażel Linux għas-server OS, u l-kmand ddpt (http://sg.danny.cz/sg/ddpt.html) intgħażel bħala l-għodda tal-ikkupjar. Billi tuża din il-kombinazzjoni, tista 'tikkopja kwalunkwe volum minn kwalunkwe OS, peress li l-ikkupjar iseħħ blokk b'blokk fuq in-naħa tas-sistema tal-ħażna. Peress li huwa meħtieġ li tikkopja blokk b'blokk, u n-numru ta 'blokki għandu jingħadd, il-kmand blockdev intuża biex jingħadd in-numru ta' tali iterazzjonijiet. Id-daqs massimu tal-blokk inkiseb b'mod sperimentali; ddpt fil-fatt ma ħadimx bi blokka kbira. Ir-riżultat kien l-iskrittura pjuttost sempliċi li ġejja:

#!/bin/bash
# first parameter = input device
# second parameter = output device
# device size must be the same
# changing bs variable can reduce speed, max speed should be at bs=32768. 32768 is max setting, lower settings should be calculated dividing by 2

set -o nounset
bs=32768
s=`blockdev --getsz $1`
i=0
while [ $i -le $s ]
do
ddpt of=$2 bs=512 oflag=xcopy,direct if=$1 iflag=xcopy,direct count=$bs verbose=-1 skip=$i seek=$i
i=$(( $i+$bs ))
done

Ejja nagħmlu ftit kontroll! Ukoll, bħala wieħed żgħir, fajl 1TB ma nħoloqx u ċċekkjat malajr minn md5sum :)

root@sales-demo-05:/home/vasilyk# blockdev --getsz /dev/mapper/mpathfs
2516582400
root@sales-demo-05:/home/vasilyk# blockdev --getsz /dev/mapper/mpathfr
2516582400
root@sales-demo-05:/home/vasilyk# mount /dev/mapper/mpathfs /xcopy_source/
mount: /xcopy_source: wrong fs type, bad option, bad superblock on /dev/mapper/mpathfs, missing codepage or helper program, or other error.
root@sales-demo-05:/home/vasilyk# mkfs /dev/mapper/mpathfs
mke2fs 1.44.1 (24-Mar-2018)
Discarding device blocks: done
Creating filesystem with 314572800 4k blocks and 78643200 inodes
Filesystem UUID: bed3ea00-c181-4b4e-b52e-d9bb498be756
Superblock backups stored on blocks:
        32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
        4096000, 7962624, 11239424, 20480000, 23887872, 71663616, 78675968,
        102400000, 214990848

Allocating group tables: done
Writing inode tables: done
Writing superblocks and filesystem accounting information: done

root@sales-demo-05:/home/vasilyk# mount /dev/mapper/mpathfs /xcopy_source/
root@sales-demo-05:/home/vasilyk# ls -l /xcopy_source/
total 16
drwx------ 2 root root 16384 Aug 19 15:35 lost+found
root@sales-demo-05:/home/vasilyk# head -c 1T </dev/urandom > /xcopy_source/1TB_file
root@sales-demo-05:/home/vasilyk# ls -l /xcopy_source/
total 1074791444
-rw-r--r-- 1 root root 1099511627776 Aug 19 17:25 1TB_file
drwx------ 2 root root         16384 Aug 19 15:35 lost+found
root@sales-demo-05:/home/vasilyk# umount /xcopy_source
root@sales-demo-05:/home/vasilyk# mount /dev/mapper/mpathfr /xcopy_dest/
mount: /xcopy_dest: wrong fs type, bad option, bad superblock on /dev/mapper/mpathfr, missing codepage or helper program, or other error.
root@sales-demo-05:/home/vasilyk# cat xcopy.sh
#!/bin/bash
# first parameter = input device
# second parameter = output device
# device size must be the same
# changing bs variable can reduce speed, max speed should be at bs=32768. 32768 is max setting, lower settings should be calculated dividing by 2

bs=32768
s=`blockdev --getsz $1`
i=0
while [ $i -le $s ]
do
ddpt of=$2 bs=512 oflag=xcopy,direct if=$1 iflag=xcopy,direct count=$bs verbose=-1 skip=$i seek=$i
i=$(( $i+$bs ))
done
root@sales-demo-05:/home/vasilyk# time ./xcopy.sh /dev/mapper/mpathfs /dev/mapper/mpathfr
real    11m30.878s
user    2m3.000s
sys     1m11.657s

X'kien qed jiġri fuq is-sistema tal-ħażna f'dak il-mument:

Ejja nkomplu bil-Linux.

root@sales-demo-05:/home/vasilyk# mount /dev/mapper/mpathfr /xcopy_dest/
root@sales-demo-05:/home/vasilyk# ls -l /xcopy_dest/
total 1074791444
-rw-r--r-- 1 root root 1099511627776 Aug 19 17:25 1TB_file
drwx------ 2 root root         16384 Aug 19 15:35 lost+found
root@sales-demo-05:/home/vasilyk# mount /dev/mapper/mpathfs /xcopy_source/
root@sales-demo-05:/home/vasilyk# md5sum /xcopy_source/1TB_file
53dc6dfdfc89f099c0d5177c652b5764  /xcopy_source/1TB_file
root@sales-demo-05:/home/vasilyk# md5sum /xcopy_dest/1TB_file
53dc6dfdfc89f099c0d5177c652b5764  /xcopy_dest/1TB_file
root@sales-demo-05:/home/vasilyk#

Kollox ħadem, imma ttestja u uża għar-riskju tiegħek! Bħala volum tas-sors, huwa aħjar li tieħu snapshots, biex nibdew.

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