lvm layout.docx

8/9/2019 LVM Layout.docx

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LVM Layout

Basically LVM looks like this:

You have one or more physical volumes (/dev/sdb1- /dev/sde1in our example), and on these

physical volumes you create one or more volume groups (eg fileserver), and in each volume group

you can create one or more logical volumes !" you use multiple physical volumes, each logical volume

can #e #igger than one o" the underlying physical volumes (#ut o" course the sum o" the logical

volumes cannot exceed the total space o""ered #y the physical volumes)

!t is a good practice to not allocate the "ull space to logical volumes, #ut leave some space unused

$hat %ay you can enlarge one or more logical volumes later on i" you "eel the need "or it

!n this example %e %ill create a volume group called fileserver, and %e %ill also create the logical

volumes /dev/fileserver/share, /dev/fileserver/backup, and /dev/fileserver/media(%hich

%ill use only hal" o" the space o""ered #y our physical volumes "or no% - that %ay %e can s%itch to

&'! later on (also descri#ed in this tutorial))

3 Our First LVM Setup

Let*s "ind out a#out our hard disks:

fdisk -l

$he output looks like this:

server1:~# fdisk -l

Disk /dev/sda: 21.4 GB, 21474!"4 b$%es

2&& heads, "! sec%'rs/%rack, 2"1 c$li(ders

)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es

Device B''% %ar% (d Bl'cks d $s%em

/dev/sda1 + 1 1 144&&! ! 0i(u

/dev/sda2 1 24& 1&!&4 ! 0i(u

/dev/sda4 24&1 2"1 12&2 2 0i(u s3ap / 'laris

Disk /dev/sdb: &. GB, &!4&2 b$%es

2&& heads, "! sec%'rs/%rack, 144! c$li(ders

)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es

Disk /dev/sdb d'es(% c'(%ai( a valid par%i%i'( %able


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Disk /dev/sdc: &. GB, &!4&2 b$%es


)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es

Disk /dev/sdc d'es(% c'(%ai( a valid par%i%i'( %able

Disk /dev/sdd: &. GB, &!4&2 b$%es


)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es

Disk /dev/sdd d'es(% c'(%ai( a valid par%i%i'( %able

Disk /dev/sde: &. GB, &!4&2 b$%es


)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es

Disk /dev/sde d'es(% c'(%ai( a valid par%i%i'( %able

Disk /dev/sdf: &. GB, &!4&2 b$%es


)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es

Disk /dev/sdf d'es(% c'(%ai( a valid par%i%i'( %able

$here are no partitions yet on /dev/sdb- /dev/sdf +e %ill create the

partitions /dev/sdb1, /dev/sdc1, /dev/sdd1, and /dev/sde1and leave /dev/sdfuntouched "or no%

+e act as i" our hard disks had only .B o" space instead o" /0.B "or no%, there"ore %e assign .B

to /dev/sdb1, /dev/sdc1, /dev/sdd1, and /dev/sde1:

fdisk /dev/sdb

server1:~# fdisk /dev/sdb

5he (umber 'f c$li(ders f'r %his disk is se% %' 144!.

5here is ('%hi(6 3r'(6 3i%h %ha%, bu% %his is lar6er %ha( 124,

a(d c'uld i( cer%ai( se%ups cause pr'blems 3i%h:

1 s'f%3are %ha% ru(s a% b''% %ime 8e.6., 'ld versi'(s 'f 009

2 b''%i(6 a(d par%i%i'(i(6 s'f%3are fr'm '%her 9s

8e.6., D9 D;, 9/2 D;


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( add a (e3 par%i%i'(

' crea%e a (e3 emp%$ D9 par%i%i'( %able

p pri(% %he par%i%i'( %able

= =ui% 3i%h'u% savi(6 cha(6es

s crea%e a (e3 emp%$ u( disklabel

% cha(6e a par%i%i'(s s$s%em id

u cha(6e displa$/e(%r$ u(i%s

v verif$ %he par%i%i'( %able

3 3ri%e %able %' disk a(d ei%

e%ra fu(c%i'(ali%$ 8eper%s '(l$

la( 2 0i(u s3ap / ' c1 DFD9/sec 8C5-

! EE usr !c >ar%i%i'(@a6ic ! 0i(u c4 DFD9/sec 8C5-4 C51" !2@ 4 He(i 2" 4 9/2 hidde( /5 4d IE4. 7 5 v'lume se% db /@ /


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1c Aidde( & C5! 7& >


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)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es


/dev/sdd1 1 !4 24417" e 0i(u 0H@



)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es


/dev/sde1 1 !4 24417" e 0i(u 0H@



)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es

Disk /dev/sdf d'es(% c'(%ai( a valid par%i%i'( %able

1o% %e prepare our ne% partitions "or LVM:

pvcrea%e /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1

server1:~# pvcrea%e /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1

>h$sical v'lume L/dev/sdb1L successfull$ crea%ed

>h$sical v'lume L/dev/sdc1L successfull$ crea%ed

>h$sical v'lume L/dev/sdd1L successfull$ crea%ed

>h$sical v'lume L/dev/sde1L successfull$ crea%ed

Let*s revert this last action "or training purposes:

pvrem've /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1

server1:~# pvrem've /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1

0abels '( ph$sical v'lume L/dev/sdb1L successfull$ 3iped

0abels '( ph$sical v'lume L/dev/sdc1L successfull$ 3iped

0abels '( ph$sical v'lume L/dev/sdd1L successfull$ 3iped

0abels '( ph$sical v'lume L/dev/sde1L successfull$ 3iped

$hen run


again:

server1:~# pvcrea%e /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1

>h$sical v'lume L/dev/sdb1L successfull$ crea%ed


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>h$sical v'lume L/dev/sdc1L successfull$ crea%ed

>h$sical v'lume L/dev/sdd1L successfull$ crea%ed

>h$sical v'lume L/dev/sde1L successfull$ crea%ed

1o% run

pvdispla$

to learn a#out the current state o" your physical volumes:

server1:~# pvdispla$

--- >h$sical v'lume ---

>H ame /dev/sdb1

HG ame

>H i?e 2!.2 GB

Cll'ca%able 9

> i?e 8;B$%e

5'%al >

ree >

Cll'ca%ed >

>H ))D Glu20-AiM1-Hde-s9;c-9'H-fad6-Nd1v$)


>H ame /dev/sdc1

HG ame

>H i?e 2!.2 GB

Cll'ca%able 9

> i?e 8;B$%e

5'%al > ree >

Cll'ca%ed >

>H ))D 4GN$h-bs-p?h(-5DF=->I!l-!u%-CH4B


>H ame /dev/sdd1

HG ame

>H i?e 2!.2 GB

Cll'ca%able 9

> i?e 8;B$%e

5'%al > ree >

Cll'ca%ed >

>H ))D 4m)"!D-4s2"-u0-rp9-Ih>-mvIF-2ON&B


>H ame /dev/sde1

HG ame

>H i?e 2!.2 GB


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Cll'ca%able 9

> i?e 8;B$%e

5'%al >

ree >

Cll'ca%ed >

>H ))D !upcJc-4e2-h4r4-iB;;-6JNv-CO%!-;dF;"

1o% let*s create our volume group fileserverand add /dev/sdb1- /dev/sde1to it:

v6crea%e fileserver /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1

server1:~# v6crea%e fileserver /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1

H'lume 6r'up LfileserverL successfull$ crea%ed

Let*s learn a#out our volume groups:

v6displa$

server1:~# v6displa$

--- H'lume 6r'up ---

HG ame fileserver

$s%em D

'rma% lvm2

@e%ada%a Creas 4

@e%ada%a e=ue(ce ' 1

HG Cccess read/3ri%e

HG %a%us resi?able

@CE 0H

H

H 4

Cc% >H 4

HG i?e !.14 GB

> i?e 4. @B


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5'%al > 2!44

Cll'c > / i?e /

ree > / i?e 2!44 / !.14 GB

HG ))D !O1H-B05-Ik;s-I(rs-J-3r9-d5=h>

'nother command to learn a#out our volume groups:

v6sca(

server1:~# v6sca(

Feadi(6 all ph$sical v'lumes. 5his ma$ %ake a 3hile...

'u(d v'lume 6r'up LfileserverL usi(6 me%ada%a %$pe lvm2

2or training purposes let*s rename our volumegroup fileserverinto da%a:

v6re(ame fileserver da%a

server1:~# v6re(ame fileserver da%a

H'lume 6r'up LfileserverL successfull$ re(amed %' Lda%aL

Let*s run v6displa$and v6sca(again to see i" the volume group has #een renamed:

v6displa$



HG ame da%a

$s%em D

'rma% lvm2

@e%ada%a Creas 4

@e%ada%a e=ue(ce ' 2


HG %a%us resi?able

@CE 0H

H

H 4

Cc% >H 4

HG i?e !.14 GB

> i?e 4. @B

5'%al > 2!44

Cll'c > / i?e /

ree > / i?e 2!44 / !.14 GB

HG ))D !O1H-B05-Ik;s-I(rs-J-3r9-d5=h>

v6sca(


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server1:~# lvcrea%e --(ame media --si?e 1G fileserver

0'6ical v'lume LmediaL crea%ed

Let*s get an overvie% o" our logical volumes:

lvdispla$

server1:~# lvdispla$

--- 0'6ical v'lume ---

0H ame /dev/fileserver/share

HG ame fileserver

0H ))D 2@up-Aaa-s(-CEA!-4c>-H"p-lf'G6N

0H ri%e Cccess read/3ri%e

0H %a%us available

# 'pe(

0H i?e 4. GB


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Fead ahead sec%'rs

Bl'ck device 2&!:2

lvsca(

server1:~# lvsca(

C


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0H ame /dev/fileserver/films

HG ame fileserver

0H ))D usfvrv-B


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server1:~# lvreduce -01G /dev/fileserver/media

CFG: Feduci(6 ac%ive l'6ical v'lume %' 1. GB

5A @CO D5F9O O9)F DC5C 8files$s%em e%c.

D' $'u reall$ 3a(% %' reduce mediaR P$/(Q: 814-'v-2"

iles$s%em label*

9 %$pe: 0i(uBl'ck si?e*4" 8l'6*2

ra6me(% si?e*4" 8l'6*2

&242 i('des, 14&7" bl'cks

&242 bl'cks 8&.S reserved f'r %he super user

irs% da%a bl'ck*

@aimum files$s%em bl'cks*

!2 bl'ck 6r'ups

!27" bl'cks per 6r'up, !27" fra6me(%s per 6r'up
http://www.howtoforge.com/linux_lvm_p2#comment-24999http://www.howtoforge.com/linux_lvm_p2#comment-24999


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1"!4 i('des per 6r'up

uperbl'ck backups s%'red '( bl'cks:

!27", !4, 1"!4, 22!7", 2412, 12, 47!", 1"&"!2, 2"&42,

4", 7"2"24

ri%i(6 i('de %ables: d'(e


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N'ur(al i?e 1! bl'cks 8firs% bl'ck 1

N'ur(al @a %ra(sac%i'( le(6%h 124

i('de 6e(era%i'( (umber:

))D: 2bebf7&-"e&-47b2-b"-1"fa7ea&!

C5559: O9) A9)0D FB995 C5F D;K

C00 DC5C 00 B 095 9 /dev/fileserver/mediaK


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9ongratulations, you*ve ust set up your "irst LVM system; You can no% %rite to and read

"rom /var/share, /var/backup, and /var/mediaas usual

+e have mounted our logical volumes manually, #ut o" course %e*d like to have them mounted

automatically %hen the system #oots $here"ore %e modi"y /e%c/fs%ab:

mv /e%c/fs%ab /e%c/fs%abT'ri6

ca% /dev/(ull U /e%c/fs%ab

vi /e%c/fs%ab


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df -h

again !t should still sho% our logical volumes in the output:

server1:~# df -hiles$s%em i?e )sed Cvail )seS @'u(%ed '(

/dev/sda2 1G ""&@ 17G 4S /

%mpfs 7@ 7@ S /lib/i(i%/r3

udev 1@ ; 1@ 1S /dev

%mpfs 7@ 7@ S /dev/shm

/dev/sda1 1!7@ 17@ 114@ 1!S /b''%

/dev/mapper/fileserver-share

4G 177@ !G 1S /var/share

/dev/mapper/fileserver-backup

&.G 144; &.G 1S /var/backup

/dev/mapper/fileserver-media

1.G !!@ 2@ 4S /var/media

4 Resize Logical Volumes And Their Filesystems

!n this chapter %e %ill learn ho% to resi=e our logical volume share%hich

has an ext8 "ilesystem (! %ill sho% ho% to resi=e logical volumes %ith x"s

and reiser"s "ilesystems "urther do%n this tutorial)

2irst %e must unmount it:

um'u(% /var/share

shareshould not #e listed anymore in the

df -h

output:

server1:~# df -h

iles$s%em i?e )sed Cvail )seS @'u(%ed '(


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/dev/sda2 1G ""&@ 17G 4S /




/dev/sda1 1!7@ 17@ 114@ 1!S /b''%





1o% let*s enlarge share"rom 30.B to 0.B:

lve%e(d -0&G /dev/fileserver/share

server1:~# lve%e(d -0&G /dev/fileserver/share

%e(di(6 l'6ical v'lume share %' &. GB

0'6ical v'lume share successfull$ resi?ed

7ntil no% %e have enlarged only share, #ut not the ext8 "ilesystem on share $his is %hat %e do no%:

e2fsck -f /dev/fileserver/share

server1:~# e2fsck -f /dev/fileserver/share

e2fsck 1.4-> 814-'v-2"

>ass 1: ass 2: ass &: 814-'v-2"

Fesi?i(6 %he files$s%em '( /dev/fileserver/share %' 1!172 84k bl'cks.

5he files$s%em '( /dev/fileserver/share is ('3 1!172 bl'cks l'(6.

Let*s mount share:


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m'u(% /dev/fileserver/share /var/share

and in the

df -h

output share should no% have 0.B instead o" 30:

server1:~# df -h


/dev/sda2 1G ""&@ 17G 4S /




/dev/sda1 1!7@ 17@ 114@ 1!S /b''%






&G 1@ 47G 1S /var/share

5hrinking a logical volume is the other %ay round: "irst %e must shrink the "ilesystem #e"ore %e

reduce the logical volume*s si=e Let*s shrink share to 30.B again:

um'u(% /var/share

df -h

server1:~# df -h


/dev/sda2 1G ""&@ 17G 4S /




/dev/sda1 1!7@ 17@ 114@ 1!S /b''%






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e2fsck -f /dev/fileserver/share

server1:~# e2fsck -f /dev/fileserver/share

e2fsck 1.4-> 814-'v-2"

>ass 1: ass 2: ass &:


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$he output o"

df -h

should no% look like this:

server1:~# df -h


/dev/sda2 1G ""&@ 17G 4S /




/dev/sda1 1!7@ 17@ 114@ 1!S /b''%







5 Adding A Hard Drive And Removing Another One

+e haven*t used /dev/sdfuntil no% +e %ill no% create thepartition /dev/sdf1(.B) and add that to our fileservervolume group

fdisk /dev/sdf


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server1:~# fdisk /dev/sdf

Device c'(%ai(s (ei%her a valid D9 par%i%i'( %able, ('r u(, G 'r 9 disklabel

Buildi(6 a (e3 D9 disklabel.


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H &

HG i?e 11".4! GB

> i?e 4. @B

5'%al > 2&


24/53

Cll'c > / i?e 1177" / 4". GB

ree > / i?e 12 / 7.4! GB

HG ))D ir1Hk-7h7N-h0F0-Ab-!p7-F=47-01G$9

$hat*s it /dev/sdf1has #een added to the "ileserver volume group

1o% let*s remove /dev/sdb1 Be"ore %e do this, %e must copy all data on it to /dev/sdf1:

pvm've /dev/sdb1 /dev/sdf1

$his can take some minutes:

server1:~# pvm've /dev/sdb1 /dev/sdf1

/dev/sdb1: @'ved: 1.S

/dev/sdb1: @'ved: !.S

/dev/sdb1: @'ved: &.S


/dev/sdb1: @'ved: .7S

/dev/sdb1: @'ved: 11."S

/dev/sdb1: @'ved: 1!."S

/dev/sdb1: @'ved: 1&."S

/dev/sdb1: @'ved: 17.&S

/dev/sdb1: @'ved: 1.4S


P...Q

/dev/sdb1: @'ved: &.7S

/dev/sdb1: @'ved: 7.7S /dev/sdb1: @'ved: .7S


/dev/sdb1: @'ved: !."S

/dev/sdb1: @'ved: &.&S

/dev/sdb1: @'ved: 7.&S

/dev/sdb1: @'ved: .4S


1ext %e remove /dev/sdb1"rom the fileservervolume group:

v6reduce fileserver /dev/sdb1

server1:~# v6reduce fileserver /dev/sdb1

Fem'ved L/dev/sdb1L fr'm v'lume 6r'up LfileserverL


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v6displa$



HG ame fileserver

$s%em D

'rma% lvm2

@e%ada%a Creas 4

@e%ada%a e=ue(ce ' 1"


HG %a%us resi?able

@CE 0H

H

H 4

Cc% >H 4

HG i?e !.14 GB

> i?e 4. @B

5'%al > 2!44

Cll'c > / i?e 1177" / 4". GB

ree > / i?e 12" / 47.14 GB

HG ))D ir1Hk-7h7N-h0F0-Ab-!p7-F=47-01G$9

$hen %e run

pvrem've /dev/sdb1

/dev/sdb1shouldn*t #e listed as a physical volume anymore:

pvdispla$



>H ame /dev/sdc1

HG ame fileserver

>H i?e 2!.2 GB / ('% usable

Cll'ca%able $es

> i?e 8;B$%e 4"

5'%al > &"1

ree > 1"2

Cll'ca%ed > 427


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>H ))D 4GN$h-bs-p?h(-5DF=->I!l-!u%-CH4B


>H ame /dev/sdd1

HG ame fileserver


Cll'ca%able $es

> i?e 8;B$%e 4"

5'%al > &"1

ree > 4"1

Cll'ca%ed > 12

>H ))D 4m)"!D-4s2"-u0-rp9-Ih>-mvIF-2ON&B


>H ame /dev/sde1

HG ame fileserver


Cll'ca%able $es

> i?e 8;B$%e 4"

5'%al > &"1

ree > &7&

Cll'ca%ed > 2&"

>H ))D !upcJc-4e2-h4r4-iB;;-6JNv-CO%!-;dF;"


>H ame /dev/sdf1

HG ame fileserver


Cll'ca%able $es 8bu% full > i?e 8;B$%e 4"

5'%al > &"1

ree >

Cll'ca%ed > &"1

>H ))D 16'2-BMM-@C?-lmDu-90J1-!d9-m0k2

You could no% remove /dev/sdb"rom the system (i" this %as a real system and not a virtual

machine)

6 Return To The ystem!s Original tate


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!n this chapter %e %ill undo all changes "rom the previous chapters to return

to the system*s original state $his is ust "or training purposes so that youlearn ho% to undo an LVM setup

2irst %e must unmount our logical volumes:

um'u(% /var/share

um'u(% /var/backup

um'u(% /var/media

df -h

server1:~# df -h


/dev/sda2 1G ""&@ 17G 4S /

%mpfs 7@ 7@ S /lib/i(i%/r3udev 1@ 2; 1@ 1S /dev


/dev/sda1 1!7@ 17@ 114@ 1!S /b''%

$hen %e delete each o" them:

lvrem've /dev/fileserver/share

server1:~# lvrem've /dev/fileserver/share

D' $'u reall$ 3a(% %' rem've ac%ive l'6ical v'lume LshareLR P$/(Q:


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server1:~# v6rem've fileserver

H'lume 6r'up LfileserverL successfull$ rem'ved

2inally %e do this:

pvrem've /dev/sdc1 /dev/sdd1 /dev/sde1 /dev/sdf1

server1:~# pvrem've /dev/sdc1 /dev/sdd1 /dev/sde1 /dev/sdf1

0abels '( ph$sical v'lume L/dev/sdc1L successfull$ 3iped

0abels '( ph$sical v'lume L/dev/sdd1L successfull$ 3iped

0abels '( ph$sical v'lume L/dev/sde1L successfull$ 3iped

0abels '( ph$sical v'lume L/dev/sdf1L successfull$ 3iped

v6displa$


' v'lume 6r'ups f'u(d

pvdispla$

should display nothing at all:


1o% %e must undo our changes in /e%c/fs%abto avoid that the system tries to mount non-existing

devices 2ortunately %e have made a #ackup o" the original "ile that %e can copy #ack no%:

mv /e%c/fs%abT'ri6 /e%c/fs%ab

&e#oot the system:

shu%d'3( -r ('3

'"ter%ards the output o"

df -h

should look like this:

server1:~# df -h


/dev/sda2 1G """@ 17G 4S /


udev 1@ 2; 1@ 1S /dev


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/dev/sda1 1!7@ 17@ 114@ 1!S /b''%

1o% the system is like it %as in the #eginning (except that the partitions /dev/sdb1- /dev/sdf1still

exist - you could delete them %ith fdisk#ut %e don*t do this no% - as %ell as the

directories /var/share,/var/backup, and /var/media%hich %e also don*t delete)

7 LVM On RAID1

!n this chapter %e %ill set up LVM again and move it to a &'! array to

guarantee "or high-availa#ility !n the end this should look like this:

$his means %e %ill make the &'! array /dev/md"rom the partitions /dev/sdb1? /dev/sdc1, and

the &'! array /dev/md1"rom the partitions /dev/sdd1? /dev/sde1 /dev/mdand /dev/md1%ill

then #e the physical volumes "or LVM

Be"ore %e come to that, %e set up LVM as #e"ore:


v6crea%e fileserver /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1

lvcrea%e --(ame share --si?e 4G fileserver

lvcrea%e --(ame backup --si?e &G fileserver

lvcrea%e --(ame media --si?e 1G fileserver

mkfs.e%! /dev/fileserver/share

mkfs.fs /dev/fileserver/backup

mkfs.reiserfs /dev/fileserver/media

$hen %e mount our logical volumes:


m'u(% /dev/fileserver/backup /var/backup

m'u(% /dev/fileserver/media /var/media

$he output o"


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df -h

should no% look like this:

server1:~# df -hiles$s%em i?e )sed Cvail )seS @'u(%ed '(

/dev/sda2 1G """@ 17G 4S /


udev 1@ 2; 1@ 1S /dev


/dev/sda1 1!7@ 17@ 114@ 1!S /b''%







1o% %e must move the contents o" /dev/sdc1and /dev/sde1(/dev/sdc1is the second partition o"

our "uture /dev/md, /dev/sde1the second partition o" our "uture /dev/md1) to the remaining

partitions, #ecause %e %ill a"ter%ards remove them "rom LVM and "ormat them %ith the

type fd(Linux &'! autodetect) and move them to /dev/mdresp /dev/md1

m'dpr'be dm-mirr'r

pvm've /dev/sdc1

v6reduce fileserver /dev/sdc1

pvrem've /dev/sdc1

pvdispla$



>H ame /dev/sdb1

HG ame fileserver


Cll'ca%able $es 8bu% full

> i?e 8;B$%e 4"

5'%al > &"1

ree >

Cll'ca%ed > &"1

>H ))D )DN$G-HD@2-r4"-9MI'-h!eb-c@p-4(v(vu


>H ame /dev/sdd1

HG ame fileserver


Cll'ca%able $es

> i?e 8;B$%e 4"


31/53

5'%al > &"1

ree > 4"1

Cll'ca%ed > 12

>H ))D =dB&d-!d-9&)C-;b3v-m(1$-74O-4?ubl


>H ame /dev/sde1

HG ame fileserver


Cll'ca%able $es

> i?e 8;B$%e 4"

5'%al > &"1

ree > 142"

Cll'ca%ed > 4&!&

>H ))D 4v01e-sr2@-a3Gd-=DNm-Jrh$sical v'lume ---

>H ame /dev/sdb1

HG ame fileserver



> i?e 8;B$%e 4"

5'%al > &"1

ree >

Cll'ca%ed > &"1



>H ame /dev/sdd1

HG ame fileserver


Cll'ca%able $es

> i?e 8;B$%e 4" 5'%al > &"1

ree > 14"

Cll'ca%ed > &1&

>H ))D =dB&d-!d-9&)C-;b3v-m(1$-74O-4?ubl

1o% %e "ormat /dev/sdc1%ith the type fd(Linux &'! autodetect):


32/53

fdisk /dev/sdc

server1:~# fdisk /dev/sdc






8e.6., D9 D;, 9/2 D;

la( 2 0i(u s3ap / ' c1 DFD9/sec 8C5-

! EE usr !c >ar%i%i'(@a6ic ! 0i(u c4 DFD9/sec 8C5-

4 C51" !2@ 4 He(i 2" 4 9/2 hidde( /5 4d IE4. 7 5 v'lume se% db /@ /


33/53

c & C5!2 80BC &2 /@ f BD/9 e4 peed%'r

e & C51" 80BC &! 9(5rack D@" Cu a B@ 5hi(kpad hi eb Be9 fs

f & %d 80BC &4 9(5rackD@" a& reeBD ee G>5

1 9>) && J-Drive a" 9pe(BD ef 8C5-12/1"/

11 Aidde( C512 &" G'lde( B'3 a7 eE55> f 0i(u/>C-F< b

12 riam disk a Dar3i( ) f1 peed%'r

14 Aidde( C51" ! "1 peed%'r a e%BD f4 peed%'r

1" Aidde( C51" "! G) A)FD 'r $s ab Dar3i( b''% f2 D9 sec'(dar$

17 Aidde( A>/5 "4 'vell e%3are b7 BD fs fd 0i(u raid au%'

1 C5 mar%leep "& 'vell e%3are b BD s3ap fe 0Cs%ep

1b Aidde( & C5! 7 Diskecure @ul% bb B''% i?ard hid ff BB5

1c Aidde( & C5! 7& >


34/53

/dev/sdb1 1 !4 24417" e 0i(u 0H@



)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es


/dev/sdc1 1 !4 24417" fd 0i(u raid au%'de%ec%



)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es


/dev/sdd1 1 !4 24417" e 0i(u 0H@



)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es


/dev/sde1 1 !4 24417" fd 0i(u raid au%'de%ec%



)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es


/dev/sdf1 1 !4 24417" e 0i(u 0H@1ext %e add /dev/sdc1to /dev/mdand /dev/sde1to /dev/md1 Because the second nodes

(/dev/sdb1and /dev/sdd1) are not ready yet, %e must speci"y missi(6in the "ollo%ing commands:

mdadm --crea%e /dev/md --au%'*$es -l 1 -( 2 /dev/sdc1 missi(6

server1:~# mdadm --crea%e /dev/md --au%'*$es -l 1 -( 2 /dev/sdc1 missi(6

mdadm: arra$ /dev/md s%ar%ed.

mdadm --crea%e /dev/md1 --au%'*$es -l 1 -( 2 /dev/sde1 missi(6

server1:~# mdadm --crea%e /dev/md1 --au%'*$es -l 1 -( 2 /dev/sde1 missi(6

mdadm: arra$ /dev/md1 s%ar%ed.

'"ter%ards %e prepare /dev/mdand /dev/md1"or LVM:


35/53

pvcrea%e /dev/md /dev/md1

server1:~# pvcrea%e /dev/md /dev/md1

>h$sical v'lume L/dev/mdL successfull$ crea%ed

>h$sical v'lume L/dev/md1L successfull$ crea%ed

and extend our fileservervolume group:

v6e%e(d fileserver /dev/md /dev/md1

server1:~# v6e%e(d fileserver /dev/md /dev/md1

H'lume 6r'up LfileserverL successfull$ e%e(ded

$he outputs o"

pvdispla$

and

v6displa$

should look like this:



>H ame /dev/sdb1

HG ame fileserver



> i?e 8;B$%e 4"

5'%al > &"1

ree >

Cll'ca%ed > &"1



>H ame /dev/sdd1

HG ame fileserver


Cll'ca%able $es

> i?e 8;B$%e 4"

5'%al > &"1

ree > 14"

Cll'ca%ed > &1&

>H ))D =dB&d-!d-9&)C-;b3v-m(1$-74O-4?ubl


36/53


>H ame /dev/md

HG ame fileserver


Cll'ca%able $es

> i?e 8;B$%e 4"

5'%al > &"1

ree > &"1

Cll'ca%ed >

>H ))D 7NA)E-1F2p-9MbN-E195-uae6-6F-A"?!>


>H ame /dev/md1

HG ame fileserver


Cll'ca%able $es

> i?e 8;B$%e 4"

5'%al > &"1

ree > &"1

Cll'ca%ed >

>H ))D p3I&CN-F3H;-ebC-J1!-d27d-2d>-A=5&F



HG ame fileserver

$s%em D

'rma% lvm2

@e%ada%a Creas 4

@e%ada%a e=ue(ce ' 14 HG Cccess read/3ri%e

HG %a%us resi?able

@CE 0H

H

H 4

Cc% >H 4

HG i?e !.14 GB

> i?e 4. @B

5'%al > 2!44 Cll'c > / i?e 1177" / 4". GB

ree > / i?e 12" / 47.14 GB

HG ))D dIDA5-kAf-)MFm-rmN!-9)O-G1%-aHsk1

1o% %e move the contents o" /dev/sdb1to /dev/mdand the contents o" /dev/sdd1to /dev/md1,

then %e remove /dev/sdb1and /dev/sdd1"rom LVM:

pvm've /dev/sdb1 /dev/md


37/53

pvm've /dev/sdd1 /dev/md1

v6reduce fileserver /dev/sdb1 /dev/sdd1

pvrem've /dev/sdb1 /dev/sdd1

1o% only /dev/mdand /dev/md1should #e le"t as physical volumes:

pvdispla$



>H ame /dev/md

HG ame fileserver



> i?e 8;B$%e 4"

5'%al > &"1

ree >

Cll'ca%ed > &"1



>H ame /dev/md1

HG ame fileserver


Cll'ca%able $es

> i?e 8;B$%e 4"

5'%al > &"1

ree > 14"

Cll'ca%ed > &1&


1o% %e "ormat /dev/sdb1%ith fd(Linux &'! autodetect):

fdisk /dev/sdb


5he (umber 'f c$li(ders f'r %his disk is se% %' !2"!&.





8e.6., D9 D;, 9/2 D;


38/53

a %'66le a b''%able fla6

b edi% bsd disklabel

c %'66le %he d's c'mpa%ibili%$ fla6

d dele%e a par%i%i'(

l lis% k('3( par%i%i'( %$pes

m pri(% %his me(u

( add a (e3 par%i%i'(

' crea%e a (e3 emp%$ D9 par%i%i'( %able

p pri(% %he par%i%i'( %able

= =ui% 3i%h'u% savi(6 cha(6es

s crea%e a (e3 emp%$ u( disklabel

% cha(6e a par%i%i'(s s$s%em id

u cha(6e displa$/e(%r$ u(i%s

v verif$ %he par%i%i'( %able

3 3ri%e %able %' disk a(d ei%

e%ra fu(c%i'(ali%$ 8eper%s '(l$


39/53

ca% /pr'c/mds%a%

%hen the process is "inished $he output looks like this "or an un"inished process:

server1:~# ca% /pr'c/mds%a%>ers'(ali%ies : Pli(earQ Pmul%ipa%hQ PraidQ Praid1Q Praid&Q Praid4Q Praid"Q Praid1Q

md1 : ac%ive raid1 sdd1P2Q sde1PQ

2441" bl'cks P2/1Q P)TQ

P*U...................Q rec'ver$ * ".4S 81&"&"/2441" fi(ish*1.mi( speed

*1!2;/sec

md : ac%ive raid1 sdb1P2Q sdc1PQ


P**U..................Q rec'ver$ * 1.&S 82&72"4/2441" fi(ish*2.mi( speed

*12!"!;/sec

u(used devices: ('(eU

and like this %hen the process is "inished:

server1:~# ca% /pr'c/mds%a%

>ers'(ali%ies : Pli(earQ Pmul%ipa%hQ PraidQ Praid1Q Praid&Q Praid4Q Praid"Q Praid1Q


2441" bl'cks P2/2Q P))Q


2441" bl'cks P2/2Q P))Q

u(used devices: ('(eU!" you have a look at >H i?ein the output o"

pvdispla$

you %ill see that 2 + 2!.2GB * 4".&GBare availa#le, ho%ever only 4GB 8share &GB

8backup 1GB 8media * 4"GBare used %hich means %e could extend one o" our logical devices

%ith a#out 0.B !*ve already sho%n ho% to extend an ext8 logical volume (share), so %e %ill

resi=e mediano% %hich uses reiser"s reiser"s "ilesystems can #e resi=ed %ithout unmounting:

lve%e(d -01.&G /dev/fileserver/media

server1:~# lve%e(d -01.&G /dev/fileserver/media

%e(di(6 l'6ical v'lume media %' 1.& GB

0'6ical v'lume media successfull$ resi?ed

resi?eTreiserfs /dev/fileserver/media


40/53

server1:~# resi?eTreiserfs /dev/fileserver/media

resi?eTreiserfs !.".1 82! 333.(ames$s.c'm

resi?eTreiserfs: 9(-li(e resi?i(6 fi(ished successfull$.

$he output o"

df -h

looks like this:

server1:~# df -h


/dev/sda2 1G """@ 17G 4S /


udev 1@ 2; 1@ 1S /dev%mpfs 7@ 7@ S /dev/shm

/dev/sda1 1!7@ 17@ 114@ 1!S /b''%






1.&G !!@ 1.&G !S /var/media

!" %e %ant our logical volumes to #e mounted automatically at #oot time, %e must

modi"y /e%c/fs%abagain (like in chapter 8):

mv /e%c/fs%ab /e%c/fs%abT'ri6

ca% /dev/(ull U /e%c/fs%ab

vi /e%c/fs%ab


41/53

0 0

/dev/fd0 /media/floppy0 auto r%,user,noauto 0

0

/dev/fileserver/s"are /var/s"are ext3

r%,noatime 0 0

/dev/fileserver/bac&up /var/bac&up xfs

r%,noatime 0 0

/dev/fileserver/media /var/media reiserfs

r%,noatime 0 0

!" you compare it to our #ackup o" the original "ile, /e%c/fs%abT'ri6, you %ill notice that %e added

the lines:

/dev/fileserver/share /var/share e%! r3,('a%ime

/dev/fileserver/backup /var/backup fs r3,('a%ime

/dev/fileserver/media /var/media reiserfs r3,('a%ime

1o% %e re#oot the system:

shu%d'3( -r ('3

'"ter the system has come up again, run

df -h

again !t should still sho% our logical volumes in the output:

server1:~# df -h


/dev/sda2 1G """@ 17G 4S /


udev 1@ 1; 1@ 1S /dev


/dev/sda1 1!7@ 17@ 114@ 1!S /b''%





/dev/mapper/fileserver-media 1.&G !!@ 1.&G !S /var/media

1o% %e are "inished %ith our LVM on &'! setup


42/53

" Re#lacing The Hard Dis$s %ith &igger Ones

+e are currently using "our hard disks %ith a si=e o" .B each (at least %e are acting like that) 1o%

let*s assume this isn*t enough anymore, and %e need more space in our &'! setup $here"ore %e %ill

replace our .B hard disks %ith /0.B hard disks (in "act %e %ill still use the current hard disks, #ut

use their "ull capacity no% - in the real li"e you %ould replace your old, small hard disks %ith ne%,

#igger ones)

$he procedure is as "ollo%s: "irst %e remove/dev/sdb

and/dev/sdd

"rom the &'! arrays, replace

them %ith #igger hard disks, put them #ack into the &'! arrays, and then %e do the same again

%ith /dev/sdcand /dev/sde

2irst %e mark /dev/sdb1as "ailed:

mdadm --ma(a6e /dev/md --fail /dev/sdb1

server1:~# mdadm --ma(a6e /dev/md --fail /dev/sdb1

mdadm: se% /dev/sdb1 faul%$ i( /dev/md

$he output o"

ca% /pr'c/mds%a%

looks no% like this:



md : ac%ive raid1 sdc1PQ sdb1P2Q8 2441" bl'cks P2/1Q P)TQ

md1 : ac%ive raid1 sde1PQ sdd1P1Q

2441" bl'cks P2/2Q P))Q



43/53

$hen %e remove /dev/sdb1"rom the &'! array /dev/md:

mdadm --ma(a6e /dev/md --rem've /dev/sdb1

server1:~# mdadm --ma(a6e /dev/md --rem've /dev/sdb1

mdadm: h'% rem'ved /dev/sdb1

ca% /pr'c/mds%a%



md : ac%ive raid1 sdc1PQ



2441" bl'cks P2/2Q P))Q


1o% %e do the same %ith /dev/sdd1:

mdadm --ma(a6e /dev/md1 --fail /dev/sdd1

server1:~# mdadm --ma(a6e /dev/md1 --fail /dev/sdd1

mdadm: se% /dev/sdd1 faul%$ i( /dev/md1

ca% /pr'c/mds%a%





md1 : ac%ive raid1 sde1PQ sdd1P2Q8




44/53

mdadm --ma(a6e /dev/md1 --rem've /dev/sdd1

server1:~# mdadm --ma(a6e /dev/md1 --rem've /dev/sdd1

mdadm: h'% rem'ved /dev/sdd1

ca% /pr'c/mds%a%





md1 : ac%ive raid1 sde1PQ



@n a real system you %ould no% shut it do%n, pull out the .B /dev/sdband /dev/sdd and replace

them %ith /0.B ones 's ! said #e"ore, %e don*t have to do this #ecause all hard disks already have a

capacity o" /0.B

1ext %e must "ormat /dev/sdband /dev/sdd +e must create

a /dev/sdb1resp /dev/sdd1partition, type fd(Linux &'! autodetect), si=e .B (the same

settings as on the old hard disks), and a /dev/sdb2resp /dev/sdd2partition, type fd, that cover the

rest o" the hard disks 's /dev/sdb1and /dev/sdd1are still present on our hard disks, %e only haveto create /dev/sdb2and /dev/sdd2in this special example

fdisk /dev/sdb







8e.6., D9 D;, 9/2 D;


45/53

)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es


/dev/sdb1 1 !4 24417" fd 0i(u raid au%'de%ec%


46/53

/dev/sda1 + 1 1 144&&! ! 0i(u

/dev/sda2 1 24& 1&!&4 ! 0i(u

/dev/sda4 24&1 2"1 12&2 2 0i(u s3ap / 'laris

Disk /dev/sdb: &. GB, &!4&2 b$%es


)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es


/dev/sdb1 1 !4 24417" fd 0i(u raid au%'de%ec%

/dev/sdb2 !41 144! &4"4&7 fd 0i(u raid au%'de%ec%



)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es


/dev/sdc1 1 !4 24417" fd 0i(u raid au%'de%ec%



)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es


/dev/sdd1 1 !4 24417" fd 0i(u raid au%'de%ec%

/dev/sdd2 !41 144! &4"4&7 fd 0i(u raid au%'de%ec%


2&& heads, "! sec%'rs/%rack, 144! c$li(ders)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es


/dev/sde1 1 !4 24417" fd 0i(u raid au%'de%ec%



)(i%s * c$li(ders 'f 1""& + &12 * 22&2 b$%es


/dev/sdf1 1 !4 24417" e 0i(u 0H@

Disk /dev/md1: 2&. GB, 2&47!"&12 b$%es

2 heads, 4 sec%'rs/%rack, "14"72 c$li(ders

)(i%s * c$li(ders 'f + &12 * 4" b$%es

Disk /dev/md1 d'es(% c'(%ai( a valid par%i%i'( %able

Disk /dev/md: 2&. GB, 2&47!"&12 b$%es


47/53

2 heads, 4 sec%'rs/%rack, "14"72 c$li(ders

)(i%s * c$li(ders 'f + &12 * 4" b$%es

Disk /dev/md d'es(% c'(%ai( a valid par%i%i'( %able

1o% %e add/dev/sdb1

to/dev/md

again and/dev/sdd1

to/dev/md1

:

mdadm --ma(a6e /dev/md --add /dev/sdb1

server1:~# mdadm --ma(a6e /dev/md --add /dev/sdb1

mdadm: re-added /dev/sdb1

mdadm --ma(a6e /dev/md1 --add /dev/sdd1

server1:~# mdadm --ma(a6e /dev/md1 --add /dev/sdd1

mdadm: re-added /dev/sdd1

1o% the contents o" #oth &'! arrays %ill #e synchroni=ed +e must %ait until this is "inished #e"ore

%e can go on +e can check the status o" the synchroni=ation %ith

ca% /pr'c/mds%a%

$he output looks like this during synchroni=ation:





P*U...................Q rec'ver$ * .S 8242!1"/2441" fi(ish*2.mi( speed

*127&!&;/sec



P*U...................Q rec'ver$ * ".4S 81&72"/2441" fi(ish*1.mi( speed

*1"&12;/sec


and like this %hen it*s "inished:


48/53




2441" bl'cks P2/2Q P))Q


2441" bl'cks P2/2Q P))Q


1o% %e do the same process again, this time replacing /dev/sdcand /dev/sde:

mdadm --ma(a6e /dev/md --fail /dev/sdc1

mdadm --ma(a6e /dev/md --rem've /dev/sdc1

mdadm --ma(a6e /dev/md1 --fail /dev/sde1

mdadm --ma(a6e /dev/md1 --rem've /dev/sde1

fdisk /dev/sdc

fdisk /dev/sde

mdadm --ma(a6e /dev/md --add /dev/sdc1

mdadm --ma(a6e /dev/md1 --add /dev/sde1

ca% /pr'c/mds%a%

+ait until the synchroni=ation has "inished

1ext %e create the &'! arrays /dev/md2"rom /dev/sdb2and /dev/sdc2as %ell

as /dev/md!"rom /dev/sdd2and /dev/sde2

mdadm --crea%e /dev/md2 --au%'*$es -l 1 -( 2 /dev/sdb2 /dev/sdc2

server1:~# mdadm --crea%e /dev/md2 --au%'*$es -l 1 -( 2 /dev/sdb2 /dev/sdc2

mdadm: arra$ /dev/md2 s%ar%ed.

mdadm --crea%e /dev/md! --au%'*$es -l 1 -( 2 /dev/sdd2 /dev/sde2

server1:~# mdadm --crea%e /dev/md! --au%'*$es -l 1 -( 2 /dev/sdd2 /dev/sde2

mdadm: arra$ /dev/md! s%ar%ed.

$he ne% &'! arrays must #e synchroni=ed #e"ore %e go on, so you should check

ca% /pr'c/mds%a%


49/53



md! : ac%ive raid1 sde2P1Q sdd2PQ

&4"4&12 bl'cks P2/2Q P))Q

P*U...................Q res$(c * &.1S 8!44224/&4"4&12 fi(ish*&.&mi( speed*1

"12!;/sec

md2 : ac%ive raid1 sdc2P1Q sdb2PQ

&4"4&12 bl'cks P2/2Q P))Q

P*U...................Q res$(c * &.&S 8!!12&12/&4"4&12 fi(ish*.!mi( speed*1

!7;/sec

md : ac%ive raid1 sdc1PQ sdb1P1Q

2441" bl'cks P2/2Q P))Q


2441" bl'cks P2/2Q P))Q


'"ter the synchroni=ation has "inished, %e prepare /dev/md2and /dev/md!"or LVM:

pvcrea%e /dev/md2 /dev/md!

server1:~# pvcrea%e /dev/md2 /dev/md!

>h$sical v'lume L/dev/md2L successfull$ crea%ed

>h$sical v'lume L/dev/md!L successfull$ crea%ed

and add /dev/md2and /dev/md!to our fileservervolume group:

v6e%e(d fileserver /dev/md2 /dev/md!

server1:~# v6e%e(d fileserver /dev/md2 /dev/md!

H'lume 6r'up LfileserverL successfull$ e%e(ded

1o% let*s run our +displa$commands:

pvdispla$



>H ame /dev/md

HG ame fileserver



> i?e 8;B$%e 4"

5'%al > &"1

ree >

Cll'ca%ed > &"1


50/53



>H ame /dev/md1

HG ame fileserver


Cll'ca%able $es

> i?e 8;B$%e 4"

5'%al > &"1

ree > 1

Cll'ca%ed > &4!



>H ame /dev/md2

HG ame fileserver

>H i?e &".71 GB / ('% usable

Cll'ca%able $es

> i?e 8;B$%e 4"

5'%al > 14&17

ree > 14&17

Cll'ca%ed >

>H ))D !k5'-evm-rfmf-0C-4O9N-20G&-%4NA(f


>H ame /dev/md!

HG ame fileserver

>H i?e &".71 GB / ('% usable

Cll'ca%able $es > i?e 8;B$%e 4"

5'%al > 14&17

ree > 14&17

Cll'ca%ed >

>H ))D 0E"-70IE-JGG)-dH&-MI66-5;44-)&N9M9

v6displa$



HG ame fileserver

$s%em D

'rma% lvm2

@e%ada%a Creas 4

@e%ada%a e=ue(ce ' 2"


HG %a%us resi?able

@CE 0H


51/53

H

H 4

Cc% >H 4

HG i?e 1&. GB

> i?e 4. @B

5'%al > 4&"

Cll'c > / i?e 114 / 4".& GB

ree > / i?e 2&2 / 11!.4 GB

HG ))D dIDA5-kAf-)MFm-rmN!-9)O-G1%-aHsk1

lvdispla$

server1:~# lvdispla$


0H ame /dev/fileserver/share HG ame fileserver

0H ))D bc(!9i-v!p-'$E-Il2-%?-u?7J-4DllO


0H %a%us available

# 'pe( 1

0H i?e 4. GB


52/53


0H %a%us available

# 'pe( 2

0H i?e 1.& GB


53/53


/dev/sda1 1!7@ 17@ 114@ 1!S /b''%




1G 272; 1G 1S /var/backup


1.&G !!@ 1.&G !S /var/media

$hat*s it; !" you*ve made it until here, you should no% #e used to LVM and LVM on &'!

lvm layout.docx

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