linuxism

LVM 구현  Linux / OS for Oracle  2011/08/07 02:54  http://blog.naver.com/calmim/90119895561

Linux - How to add a new disk to a volume group

The disk to add to the VG can be a single disk or a hardware raid of disks that can be seen by the fdisk command

fdisk -l

The truncated output from this command is shown below

Disk /dev/sda: 146.6 GB, 146694733824 bytes
255 heads, 63 sectors/track, 17834 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1          17      136521   83  Linux
/dev/sda2              18       17834   143115052+  8e  Linux LVM

Disk /dev/sdb: 293.3 GB, 293389467648 bytes
255 heads, 63 sectors/track, 35669 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/sdb doesn't contain a valid partition table

We can see that the disk /dev/sdb is not in use

We now need to create a partition on this disk using the fdisk command as follows

fdisk /dev/sdb

Command (m for help): p

Disk /dev/sdb: 293.3 GB, 293389467648 bytes
255 heads, 63 sectors/track, 35669 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System

Command (m for help): n
Command action
   e   extended
   p   primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-35669, default 1):
Using default value 1
Last cylinder or +size or +sizeM or +sizeK (1-35669, default 35669):
Using default value 35669

Command (m for help): p

Disk /dev/sdb: 293.3 GB, 293389467648 bytes
255 heads, 63 sectors/track, 35669 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1       35669   286511211   83  Linux

The above process creates a linux partition the same size as the disk, however we need to change the type from linux to Linux LVM as this partition will be part of Logical Volume Management (LVM)

Whilst still in the fdisk /dev/sdb utility do the following

Command (m for help): t
Selected partition 1
Hex code (type L to list codes): 8e
Changed system type of partition 1 to 8e (Linux LVM)

Command (m for help): p

Disk /dev/sdb: 293.3 GB, 293389467648 bytes
255 heads, 63 sectors/track, 35669 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1       35669   286511211   8e  Linux LVM

Command (m for help):

After the partition type has been changed use the w command to write the partition table to the disk.

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.

We now need to prepare the disk for use in LVM by using the pvcreate command

pvcreate /dev/sdb1

Physical volume "/dev/sdb1" successfully created

Now in this example we are going to extend an existing volume group to incorporate this new partition. You could however create a new VG and add it to that.

Use the vgdisplay command to see the existing volume groups

vgdisplay

 --- Volume group ---
  VG Name               system
  System ID
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  7
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                6
  Open LV               6
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               136.48 GB
  PE Size               4.00 MB
  Total PE              34940
  Alloc PE / Size       16896 / 66.00 GB
  Free  PE / Size       18044 / 70.48 GB
  VG UUID               Xcgf7x-W6FJ-OMPa-0j21-XIdt-NLFz-PshfWe

We are going to add /dev/sdb1 into the existing VG called system by using the vgextend command

vgextend system /dev/sdb1

Volume group "system" successfully extended

Use the vgdisplay command again to view the statistics for the VG. Check the Free row to ensure the free disk space in the VG has increased as shown below.

vgdisplay

 --- Volume group ---
  VG Name               system
  System ID
  Format                lvm2
  Metadata Areas        2
  Metadata Sequence No  8
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                6
  Open LV               6
  Max PV                0
  Cur PV                2
  Act PV                2
  VG Size               409.72 GB
  PE Size               4.00 MB
  Total PE              104888
  Alloc PE / Size       16896 / 66.00 GB
  Free  PE / Size       87992 / 343.72 GB
  VG UUID               Xcgf7x-W6FJ-OMPa-0j21-XIdt-NLFz-PshfWe

In this case we want to use the capacity of the new partition to create a new logical volume. This can be achieved by using the lvcreate command

lvcreate -L 293G -n logs system

Logical volume "logs" created

This command creates a 293GB logical volume called logs in the system VG

We now need to create a filesystem on the LV as follows

mkfs.ext3 /dev/system/logs

mke2fs 1.38 (30-Jun-2005)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
38404096 inodes, 76808192 blocks
3840409 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=79691776
2344 block groups
32768 blocks per group, 32768 fragments per group
16384 inodes per group
Superblock backups stored on blocks:
        32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
        4096000, 7962624, 11239424, 20480000, 23887872, 71663616

Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 35 mounts or
180 days, whichever comes first.  Use tune2fs -c or -i to override.

This creates an ext3 filesystem on the logs LV

Now all we have left to is mount the new filesystem, in this case on an existing directory called logs

mount /dev/system/logs /logs

Lastly don't forget to edit /etc/fstab so that this filesystem is mounted on boot

source - http://www.computers-it.com/linux/linux_add_new_disk_to_VG.php

 LVM 사용하여 추가한 디스크로 볼륨 늘리기

1. 디스크 먼저 추가

2. fdisk 로 해당 디스크 파티셔닝 및 파일시스템을 Linux LVM (8e) 타입으로 변경

3. 추가된 디스크 파티션  (예:/dev/sdb1) 을  LVM pv로 등록

# pvcreate /dev/sdb1

-- pv 확인

# pvdisplay

4. 볼륨그룹에 해당 pv 를 추가

-- 볼륨그룹 확인방법

# vgdisplay
  --- Volume group ---
  VG Name               VolGroup00
  System ID             
  Format                lvm2
  Metadata Areas        2
  Metadata Sequence No  6
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                2
  Open LV               2
  Max PV                0
  Cur PV                2
  Act PV                2
  VG Size               69.84 GB
  PE Size               32.00 MB
  Total PE              2235
  Alloc PE / Size       2235 / 69.84 GB
  Free  PE / Size       0 / 0   
  VG UUID               c0VfnV-tkri-vcAz-Z9Nz-bhBc-hfsX-Xdbupi

-- 볼륨그룹에 pv를 추가

# vgextend VolGroup00 /dev/sdb1

-- 볼륨그룹 증가된 부분 확인

  --- Volume group ---
  VG Name               VolGroup00
  System ID             
  Format                lvm2
  Metadata Areas        2
  Metadata Sequence No  6
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                2
  Open LV               2
  Max PV                0
  Cur PV                2
  Act PV                2
  VG Size               69.84 GB
  PE Size               32.00 MB
  Total PE              2235                    --->  증가된 부분 확인
  Alloc PE / Size       2235 / 69.84 GB
  Free  PE / Size       0 / 0                --->  남은 공간  (추가된 디스크 만큼의 용량)
  VG UUID               c0VfnV-tkri-vcAz-Z9Nz-bhBc-hfsX-Xdbupi

5. 볼륨그룹내 LV 의 크기를 증가.

vgdisplay 의 결과중 TotalPE의 크기만큼 증가시킨다.

즉, 추가할 PE만큼 늘리는게 아니라 목표하는 전체 PE의 크기만큼 지정해준다.

# lvextend -l 2235 /dev/mapper/VolGroup00-LogVol01

--  vg와 lv 를 모두 확인

# vgdisplay

# lvdisplay

  --- Logical volume ---
  LV Name                /dev/VolGroup00/LogVol01
  VG Name                VolGroup00
  LV UUID                Mlt1AT-b5aP-k1L8-355J-i9dT-3Fak-BNcmQz
  LV Write Access        read/write
  LV Status              available
  # open                 1
  LV Size                68.84 GB           --> 최종 증가된 분량 확인
  Current LE             2203
  Segments               2
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           253:0

6. 파일시스템에 적용

--> LV까지 증가시켰는데도 파일시스템이 증가하지 않는다.

수동으로 증가시켜야 한다.

# resize2fs /dev/mapper/VolGroup00-LogVol01
resize2fs 1.39 (29-May-2006)
Filesystem at /dev/mapper/VolGroup00-LogVol01 is mounted on /; on-line resizing required
Performing an on-line resize of /dev/mapper/VolGroup00-LogVol01 to 18046976 (4k) blocks.
The filesystem on /dev/mapper/VolGroup00-LogVol01 is now 18046976 blocks long.

7. 확인

# df -k   로 확인했을때 늘어난 용량을 확인할 수 있다.

출처 - http://www.ischo.net/?mid=board_linux&page=1&document_srl=1390

Thursday, July 19, 2012

I find this works better btw: lvextend -l +100%FREE /dev/vg/lv

source - http://rgheck.blogspot.kr/2012/07/how-to-add-to-lvm-drive.html

[root@db1 ~]# fdisk -l

Disk /dev/xvda: 21.5 GB, 21474836480 bytes

255 heads, 63 sectors/track, 2610 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x000a00b4

    Device Boot      Start         End      Blocks   Id  System

/dev/xvda1   *           1          64      512000   83  Linux

Partition 1 does not end on cylinder boundary.

/dev/xvda2              64        2611    20458496   8e  Linux LVM

Disk /dev/xvdb: 85.9 GB, 85899345920 bytes

255 heads, 63 sectors/track, 10443 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x00000000

Disk /dev/mapper/VolGroup-lv_root: 16.8 GB, 16752050176 bytes

255 heads, 63 sectors/track, 2036 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x00000000

Disk /dev/mapper/VolGroup-lv_swap: 4194 MB, 4194304000 bytes

255 heads, 63 sectors/track, 509 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x00000000

[root@db1 ~]# 

[root@db1 ~]# fdisk /dev/xvdb

Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel

Building a new DOS disklabel with disk identifier 0xbe92d432.

Changes will remain in memory only, until you decide to write them.

After that, of course, the previous content won't be recoverable.

Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)

WARNING: DOS-compatible mode is deprecated. It's strongly recommended to

         switch off the mode (command 'c') and change display units to

         sectors (command 'u').

Command (m for help): n

Command action

   e   extended

   p   primary partition (1-4)

p

Partition number (1-4): 1

First cylinder (1-10443, default 1): 

Using default value 1

Last cylinder, +cylinders or +size{K,M,G} (1-10443, default 10443): 

Using default value 10443

Command (m for help): t

Selected partition 1

Hex code (type L to list codes): 8e

Changed system type of partition 1 to 8e (Linux LVM)

Command (m for help): p

Disk /dev/xvdb: 85.9 GB, 85899345920 bytes

255 heads, 63 sectors/track, 10443 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0xbe92d432

    Device Boot      Start         End      Blocks   Id  System

/dev/xvdb1               1       10443    83883366   8e  Linux LVM

Command (m for help): w

The partition table has been altered!

Calling ioctl() to re-read partition table.

Syncing disks.

[root@db1 ~]# 

[root@db1 ~]# fdisk -l

Disk /dev/xvda: 21.5 GB, 21474836480 bytes

255 heads, 63 sectors/track, 2610 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x000a00b4

    Device Boot      Start         End      Blocks   Id  System

/dev/xvda1   *           1          64      512000   83  Linux

Partition 1 does not end on cylinder boundary.

/dev/xvda2              64        2611    20458496   8e  Linux LVM

Disk /dev/xvdb: 85.9 GB, 85899345920 bytes

255 heads, 63 sectors/track, 10443 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0xbe92d432

    Device Boot      Start         End      Blocks   Id  System

/dev/xvdb1               1       10443    83883366   8e  Linux LVM

Disk /dev/mapper/VolGroup-lv_root: 16.8 GB, 16752050176 bytes

255 heads, 63 sectors/track, 2036 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x00000000

Disk /dev/mapper/VolGroup-lv_swap: 4194 MB, 4194304000 bytes

255 heads, 63 sectors/track, 509 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x00000000

[root@db1 ~]# 

[root@db1 ~]# pvcreate /dev/xvdb1

  Physical volume "/dev/xvdb1" successfully created

[root@db1 ~]# 

[root@db1 ~]# vgextend VolGroup /dev/xvdb1

  Volume group "VolGroup" successfully extended

[root@db1 ~]# 

[root@db1 ~]# vgdisplay

  --- Volume group ---

  VG Name               VolGroup

  System ID             

  Format                lvm2

  Metadata Areas        2

  Metadata Sequence No  4

  VG Access             read/write

  VG Status             resizable

  MAX LV                0

  Cur LV                2

  Open LV               2

  Max PV                0

  Cur PV                2

  Act PV                2

  VG Size               99.50 GiB

  PE Size               4.00 MiB

  Total PE              25473

  Alloc PE / Size       4994 / 19.51 GiB

  Free  PE / Size       20479 / 80.00 GiB

  VG UUID               WgNnG3-6emx-ULfq-UCWD-Ca27-KAEx-dL7r3l

[root@db1 ~]# 

[root@db1 ~]# lvextend -l +100%FREE /dev/VolGroup/lv_root

  Extending logical volume lv_root to 95.60 GiB

  Logical volume lv_root successfully resized

[root@db1 ~]# 

[root@db1 ~]# lvdisplay

  --- Logical volume ---

  LV Path                /dev/VolGroup/lv_root

  LV Name                lv_root

  VG Name                VolGroup

  LV UUID                ZMnMQe-jWY7-09sS-jXX0-fL1V-pprq-0WpPXU

  LV Write Access        read/write

  LV Creation host, time localhost.localdomain, 2014-03-11 13:45:54 +0900

  LV Status              available

  # open                 1

  LV Size                95.60 GiB

  Current LE             24473

  Segments               2

  Allocation             inherit

  Read ahead sectors     auto

  - currently set to     256

  Block device           253:0

  --- Logical volume ---

  LV Path                /dev/VolGroup/lv_swap

  LV Name                lv_swap

  VG Name                VolGroup

  LV UUID                ZZSPps-ioYZ-ISdq-yjco-7Um6-dAkm-Sq0BHe

  LV Write Access        read/write

  LV Creation host, time localhost.localdomain, 2014-03-11 13:46:00 +0900

  LV Status              available

  # open                 1

  LV Size                3.91 GiB

  Current LE             1000

  Segments               1

  Allocation             inherit

  Read ahead sectors     auto

  - currently set to     256

  Block device           253:1

[root@db1 ~]# 

[root@db1 ~]# df -h

Filesystem            Size  Used Avail Use% Mounted on

/dev/mapper/VolGroup-lv_root

                       16G  2.3G   13G  16% /

tmpfs                 1.9G     0  1.9G   0% /dev/shm

/dev/xvda1            485M   54M  406M  12% /boot

[root@db1 ~]# 

[root@db1 ~]# resize2fs /dev/mapper/VolGroup-lv_root

resize2fs 1.41.12 (17-May-2010)

Filesystem at /dev/mapper/VolGroup-lv_root is mounted on /; on-line resizing required

old desc_blocks = 1, new_desc_blocks = 6

Performing an on-line resize of /dev/mapper/VolGroup-lv_root to 25060352 (4k) blocks.

The filesystem on /dev/mapper/VolGroup-lv_root is now 25060352 blocks long.

[root@db1 ~]# 

[root@db1 ~]# df -h

Filesystem            Size  Used Avail Use% Mounted on

/dev/mapper/VolGroup-lv_root

                       95G  2.3G   88G   3% /

tmpfs                 1.9G     0  1.9G   0% /dev/shm

/dev/xvda1            485M   54M  406M  12% /boot

[root@db1 ~]# 

.rhosts file policy

이 파일은 보안상 매우 위험한 파일이므로 관리를 잘해야한다.
 rlogin 명령어 Remote Login CMD
 rsh 명령어 Remote Shell CMD
 rcp 명령어 Remote Copy CMD

.rhosts file
  +     +      # 모든 호스트의 모든 유저가 내 서버로 인증없이 접속가능
hostA          # 2번째 필드가 없다면 hostA의 현재 사용중인 유저 접속가능
hostA   +      # hostA 의 모든 유저가 인증없이 접속 가능
hostA user01   # hostA 의 user01 사용자만 인증없이 접속가능.

이 파일은 2개의 필드로 구성되어 있다.
각 사용자의 홈폴더에 존재해야 사용이 가능하다.
예를 들면 user01 사용자로 인증없이 접속하고자 한다면 user01의 사용자 홈폴더에
.rhosts 파일에 정의가 되어 있어야한다.

.rhosts file management

주기적으로 찾아서 삭제해주어야한다.
# find / -name .rhosts -type f -exec rm {} \;
   ---> -type d 옵션을 준것은 관리자가 생성한 .rhosts 디렉토리를 제외시키기 위해
유저 추가시 .rhosts 파일을 생성못하도록 설정해야한다.
   /etc/skel 및에 .rhosts 디렉토리를 생성하고 그 디렉토리 안에 파일을 생성
   퍼미션을 000으로 설정해준다.

# mkdir /etc/skel/.rhosts
# touch /etc/skel/.rhosts/file
# chmod -R 000 /etc/skel/.rhosts
   ---> 디렉토리도 일종의 파일로 보기때문에 같은이름으로 파일을 생성할수가 없다.
※주의 : 유저가 mv 명령어로 .rhosts 파일을 이름을
          변경하고 .rhosts 파일을 생성 할 수 있다.


※ 호스트 이름으로 정의 할때는 /etc/hosts 파일에 정의가 되어 있어야한다.
   rlogin 할때 사용자의 uid 번호와는 상관이 없다.
   login 프로그램이 실행이되면 아이디와 비밀번호를 물어 보고 /etc/passwd
   파일에서 아이디가 있는지를 확인한다음 패스워드를 확인하고 있으면 uid가 세팅.
   그렇기 때문에 uid와는 상관이 없고 id에 연관이 있다. 하지만 접속하고 나서는  
   uid가 변경되는 것을 알수있다.