{"id":446,"date":"2017-01-09T10:10:00","date_gmt":"2017-01-09T10:10:00","guid":{"rendered":"https:\/\/visworlditsolution.wordpress.com\/?p=446"},"modified":"2017-01-09T10:10:00","modified_gmt":"2017-01-09T10:10:00","slug":"how-to-create-raid-01-over-loop-devise","status":"publish","type":"post","link":"https:\/\/linux.thingsomething.com\/index.php\/2017\/01\/09\/how-to-create-raid-01-over-loop-devise\/","title":{"rendered":"How to create Raid 01 over loop devices"},"content":{"rendered":"

hii\u00a0guys today we will learn how to create raid 01 on loop devises . if you want to know what is loop devises so click how to create loop in <\/a>redhat linux\u00a0.\u00a0so here we will start loop over raid<\/p>\n

at fast we will make two loop device a.txt, b.txt<\/strong><\/p>\n

[root@localhost\u00a0~]#\u00a0touch\u00a0a.txt<\/span><\/strong>
\n[root@localhost\u00a0~]#\u00a0touch b.txt<\/strong><\/span>
\n[root@localhost\u00a0~]#\u00a0touch c.txt<\/strong><\/span>
\n[root@localhost\u00a0~]#\u00a0touch d.txt<\/strong><\/span>
\n[root@localhost\u00a0~]#\u00a0touch e.txt<\/strong><\/span>
\n[root@localhost\u00a0~]#\u00a0touch f.txt<\/strong><\/span>
\n[root@localhost\u00a0~]#\u00a0touch g.txt<\/strong><\/span><\/p>\n

then we will provide txt file size blow this commands<\/p>\n

[root@localhost ~]# dd if=\/dev\/sda of=a.txt bs=2M count=100<\/strong><\/span>
\n[root@localhost ~]# dd if=\/dev\/sda of=b.txt bs=2M count=100<\/strong><\/span>
\n[root@localhost ~]# dd if=\/dev\/sda of=c.txt bs=2M count=100<\/strong><\/span>
\n[root@localhost ~]# dd if=\/dev\/sda of=d.txt bs=2M count=100<\/strong><\/span>
\n[root@localhost ~]# dd if=\/dev\/sda of=e.txt bs=2M count=100<\/strong><\/span>
\n[root@localhost ~]# dd if=\/dev\/sda of=f.txt bs=2M count=100<\/strong><\/span>
\n[root@localhost ~]# dd if=\/dev\/sda of=g.txt bs=2M count=100<\/strong><\/span>
\n[root@localhost ~]# dd if=\/dev\/sda of=h.txt bs=2M count=100<\/strong><\/span><\/p>\n

here our every file size is 200MB now we convert in loop devices blow commands
\n[root@localhost ~]# losetup \/dev\/loop0 \u00a0a.txt<\/strong><\/span>
\n [root@localhost ~]# losetup \/dev\/loop1 \u00a0b.txt<\/strong><\/span>
\n [root@localhost ~]# losetup \/dev\/loop2 \u00a0c.txt<\/strong><\/span>
\n [root@localhost ~]# losetup \/dev\/loop3 \u00a0d.txt<\/strong><\/span>
\n [root@localhost ~]# losetup \/dev\/loop4 \u00a0e.txt<\/strong><\/span>
\n [root@localhost ~]# losetup \/dev\/loop5 \u00a0f.txt<\/strong><\/span>
\n [root@localhost ~]# losetup \/dev\/loop6 \u00a0g.txt<\/strong><\/span>
\n [root@localhost ~]# losetup \/dev\/loop7 \u00a0h.txt<\/strong><\/span><\/p>\n

now we can look over loop devices through this commands [root@localhost ~]# losetup -a<\/strong><\/p>\n

[root@localhost ~]# losetup -a<\/strong><\/p>\n

\/dev\/loop0: [0801]:5197237 (a.txt)<\/strong><\/span>
\n \/dev\/loop1: [0801]:5197240 (b.txt)<\/strong><\/span>
\n \/dev\/loop2: [0801]:5197247 (c.txt)<\/strong><\/span>
\n \/dev\/loop3: [0801]:5197242 (d.txt)<\/strong><\/span>
\n \/dev\/loop4: [0801]:5197243 (e.txt)<\/strong><\/span>
\n \/dev\/loop5: [0801]:5197244 (f.txt)<\/strong><\/span>
\n \/dev\/loop6: [0801]:5197245 (g.txt)<\/strong><\/span>
\n\/dev\/loop7: [0801]:5197246 (h.txt)<\/strong><\/span><\/p>\n

now here we will configure raid 01 . \u00a0before we create raid 0 .
\n[root@localhost ~]# mdadm –create \/dev\/md1 –level=0 –raid-device=2 \/dev\/loop0 \/dev\/loop1<\/span>
\nmdadm: \/dev\/loop0 appears to be part of a raid array:<\/span>
\n level=raid1 devices=2 ctime=Mon Jan 9 06:53:32 2017<\/span>
\n mdadm: \/dev\/loop1 appears to be part of a raid array:<\/span>
\n level=raid1 devices=2 ctime=Mon Jan 9 06:53:32 2017<\/span>
\n Continue creating array? yes<\/strong><\/span><\/span>
\n mdadm: array \/dev\/md1 started.<\/span>
\n [root@localhost ~]# mdadm –create \/dev\/md2 –level=0 –raid-device=2 \/dev\/loop2 \/dev\/loop3<\/span>
\n mdadm: \/dev\/loop2 appears to contain an ext2fs file system<\/span>
\n size=204800K mtime=Thu Jan 1 05:30:00 1970<\/span>
\n mdadm: \/dev\/loop2 appears to be part of a raid array:<\/span>
\n level=raid1 devices=2 ctime=Mon Jan 9 06:54:01 2017<\/span>
\n mdadm: \/dev\/loop3 appears to contain an ext2fs file system<\/span>
\n size=204800K mtime=Thu Jan 1 05:30:00 1970<\/span>
\n mdadm: \/dev\/loop3 appears to be part of a raid array:<\/span>
\n level=raid1 devices=2 ctime=Mon Jan 9 06:54:01 2017<\/span>
\n Continue creating array? yes<\/span><\/strong><\/span>
\n mdadm: array \/dev\/md2 started.<\/span><\/p>\n

\"loop<\/p>\n

here we have two md group md1 md2.\u00a0<\/strong>and we used total 4 loop devises in both md group\u00a0<\/span><\/span><\/p>\n

then we will have four free loop devises \u00a0so we create another group md3 and md 4<\/strong><\/span><\/p>\n

 <\/p>\n

[root@localhost ~]# mdadm –create \/dev\/md3 –level=0 –raid-device=2 \/dev\/loop4 \/dev\/loop5<\/span>
\nmdadm: \/dev\/loop4 appears to contain an ext2fs file system<\/span>
\n size=204800K mtime=Thu Jan 1 05:30:00 1970<\/span>
\n mdadm: \/dev\/loop4 appears to be part of a raid array:<\/span>
\n level=raid1 devices=2 ctime=Mon Jan 9 06:54:55 2017<\/span>
\n mdadm: \/dev\/loop5 appears to contain an ext2fs file system<\/span>
\n size=204800K mtime=Thu Jan 1 05:30:00 1970<\/span>
\n mdadm: \/dev\/loop5 appears to be part of a raid array:<\/span>
\n level=raid1 devices=2 ctime=Mon Jan 9 06:54:55 2017<\/span>
\n Continue creating array? yes<\/span><\/strong><\/span>
\n mdadm: array \/dev\/md3 started.<\/span>
\n[root@localhost ~]# mdadm –create \/dev\/md4 –level=0 –raid-device=2 \/dev\/loop6 \/dev\/loop7<\/span>
\nmdadm: \/dev\/loop6 appears to contain an ext2fs file system<\/span>
\n size=204800K mtime=Thu Jan 1 05:30:00 1970<\/span>
\n mdadm: \/dev\/loop6 appears to be part of a raid array:<\/span>
\n level=raid1 devices=2 ctime=Mon Jan 9 06:55:39 2017<\/span>
\n mdadm: \/dev\/loop7 appears to contain an ext2fs file system<\/span>
\n size=204800K mtime=Thu Jan 1 05:30:00 1970<\/span>
\n mdadm: \/dev\/loop7 appears to be part of a raid array:<\/span>
\n level=raid1 devices=2 ctime=Mon Jan 9 06:55:39 2017<\/span>
\n Continue creating array? yes<\/strong><\/span><\/span>
\n mdadm: array \/dev\/md4 started.<\/span><\/p>\n

\"raid<\/p>\n

now we have md3 and md4<\/strong> .then we will add md1 and md2.<\/strong><\/span><\/p>\n

[root@localhost ~]# mdadm –create \/dev\/md5 –level=0 –raid-device=2 \/dev\/md1 \/dev\/md2<\/span>
\nmdadm: \/dev\/md1 appears to be part of a raid array:<\/span>
\n level=raid0 devices=2 ctime=Mon Jan 9 06:58:08 2017<\/span>
\n mdadm: \/dev\/md2 appears to contain an ext2fs file system<\/span>
\n size=204800K mtime=Thu Jan 1 05:30:00 1970<\/span>
\n mdadm: \/dev\/md2 appears to be part of a raid array:<\/span>
\n level=raid0 devices=2 ctime=Mon Jan 9 06:58:08 2017<\/span>
\n Continue creating array? yes<\/span><\/strong><\/span>
\n mdadm: array \/dev\/md5 started.<\/span><\/p>\n

like same we will add md3 and md4
\n[root@localhost ~]# mdadm –create \/dev\/md6 –level=0 –raid-device=2 \/dev\/md3 \/dev\/md4<\/span>
\nmdadm: \/dev\/md3 appears to contain an ext2fs file system<\/span>
\n size=204800K mtime=Thu Jan 1 05:30:00 1970<\/span>
\n mdadm: \/dev\/md3 appears to be part of a raid array:<\/span>
\n level=raid0 devices=2 ctime=Mon Jan 9 06:58:53 2017<\/span>
\n mdadm: \/dev\/md4 appears to contain an ext2fs file system<\/span>
\n size=204800K mtime=Thu Jan 1 05:30:00 1970<\/span>
\n mdadm: \/dev\/md4 appears to be part of a raid array:<\/span>
\n level=raid0 devices=2 ctime=Mon Jan 9 06:58:53 2017<\/span>
\n Continue creating array? yes<\/strong><\/span><\/span>
\n mdadm: array \/dev\/md6 started.<\/span><\/p>\n

\"loop<\/p>\n

 <\/p>\n

now we have new md group md5 and md6 .<\/strong> Here we will create raid 1 over md5 and md 6 \u00a0then we found we create raid 01<\/span><\/span><\/p>\n

\u00a0<\/strong><\/span>
\n [root@localhost ~]# mdadm –create \/dev\/md11 –level=1 –raid-device=2 \/dev\/md5 \/dev\/md6<\/span>
\nmdadm: \/dev\/md5 appears to be part of a raid array:<\/span>
\n level=raid0 devices=2 ctime=Mon Jan 9 06:58:08 2017<\/span>
\n mdadm: \/dev\/md6 appears to contain an ext2fs file system<\/span>
\n size=204800K mtime=Thu Jan 1 05:30:00 1970<\/span>
\n mdadm: \/dev\/md6 appears to be part of a raid array:<\/span>
\n level=raid0 devices=2 ctime=Mon Jan 9 06:58:53 2017<\/span>
\n Continue creating array? yes<\/span><\/strong><\/span>
\n mdadm: array \/dev\/md11 started.<\/span><\/p>\n

\"loop
\nwe can look raid 01 through this commands # cat \/proc\/mdstat<\/strong><\/span>
\n [root@localhost ~]# cat \/proc\/mdstat<\/span>
\nPersonalities : [raid0] [raid1]<\/span>
\n md11 : active raid1 md6[1] md5[0]<\/span>
\n 818752 blocks [2\/2] [UU]<\/span>
\n md6 : active raid0 md4[1] md3[0]<\/span>
\n 818816 blocks 64k chunks<\/span>
\n md5 : active raid0 md2[1] md1[0]<\/span>
\n 818816 blocks 64k chunks<\/span>
\n md4 : active raid0 loop7[1] loop6[0]<\/span>
\n 409472 blocks 64k chunks<\/span>
\n md3 : active raid0 loop5[1] loop4[0]<\/span>
\n 409472 blocks 64k chunks<\/span>
\n md2 : active raid0 loop3[1] loop2[0]<\/span>
\n 409472 blocks 64k chunks<\/span>
\n md1 : active raid0 loop1[1] loop0[0]<\/span>
\n 409472 blocks 64k chunks<\/span>
\n unused devices:<\/span><\/p>\n

\"loop<\/p>\n

next i will show you how can we permanent mount our raid 01 \/(md11)<\/strong><\/span><\/p>\n

so before we format our md11 like this
\n[root@localhost ~]# <\/strong><\/span>mkfs.ext3 \/dev\/md11<\/strong><\/span>
\nmke2fs 1.39 (29-May-2006)<\/span>
\nFilesystem label=<\/span>
\nOS type: Linux<\/span>
\nBlock size=4096 (log=2)<\/span>
\nFragment size=4096 (log=2)<\/span>
\n102368 inodes, 204688 blocks<\/span>
\n10234 blocks (5.00%) reserved for the super user<\/span>
\nFirst data block=0<\/span>
\nMaximum filesystem blocks=209715200<\/span>
\n7 block groups<\/span>
\n32768 blocks per group, 32768 fragments per group<\/span>
\n14624 inodes per group<\/span>
\nSuperblock backups stored on blocks:<\/span>
\n32768, 98304, 163840<\/span>
\nWriting inode tables: done<\/span>
\nCreating journal (4096 blocks): done<\/span>
\nWriting superblocks and filesystem accounting information: done<\/span>
\nThis filesystem will be automatically checked every 38 mounts or<\/span>
\n180 days, whichever comes first. Use tune2fs -c or -i to override.<\/span><\/p>\n

here we will create data1 folder for md11 mounting
\n[root@localhost ~]# <\/strong>mkdir<\/strong> data1<\/strong><\/span><\/p>\n

[root@localhost ~]# mount \/dev\/md11 data1<\/span><\/strong><\/p>\n

now we do permanent mounting \u00a0just go to #vim \/etc\/fstab<\/strong><\/span>
\n[root@localhost ~]# vim \/etc\/fstab<\/strong><\/span><\/p>\n

we will add {\u00a0\/root\/data1 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \/dev\/md11 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 ext3 \u00a0 \u00a0defaults \u00a0 \u00a0 \u00a0 \u00a00 0 }<\/strong><\/span><\/p>\n

LABEL=\/                 \/                       ext3    defaults        1 1\ntmpfs                   \/dev\/shm                tmpfs   defaults        0 0\ndevpts                  \/dev\/pts                devpts  gid=5,mode=620  0 0\nsysfs                   \/sys                    sysfs   defaults        0 0\nproc                    \/proc                   proc    defaults        0 0\nLABEL=SWAP-sda2         swap                    swap    defaults        0 0\n\/root\/data1             \/dev\/md11               ext3    defaults        0 0<\/span><\/strong><\/span>\n~<\/pre>\n
\"loop<\/p>\n
now your raid 01 is complet<\/strong><\/span><\/p>\n
THANK YOU\u00a0<\/strong><\/p>\n
BY VISHNU SHARMA<\/p>\n","protected":false},"excerpt":{"rendered":"
hii\u00a0guys today we will learn how to create raid 01 on loop devises . if you want to know what is loop devises so click … Read More<\/a><\/span><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_uf_show_specific_survey":0,"_uf_disable_surveys":false,"footnotes":""},"categories":[8],"tags":[28,31,65,108,109],"class_list":["post-446","post","type-post","status-publish","format-standard","hentry","category-linux-rhel5","tag-about-loop","tag-about-raid01","tag-hoe-to-create-loop-device","tag-how-to-create-loop-over-raid01","tag-how-to-create-loop-voer-raid"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/linux.thingsomething.com\/index.php\/wp-json\/wp\/v2\/posts\/446"}],"collection":[{"href":"https:\/\/linux.thingsomething.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/linux.thingsomething.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/linux.thingsomething.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/linux.thingsomething.com\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":0,"href":"https:\/\/linux.thingsomething.com\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"wp:attachment":[{"href":"https:\/\/linux.thingsomething.com\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/linux.thingsomething.com\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/linux.thingsomething.com\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}