linux进阶

目录：
1.raid+lvm 卷
2.NIS+NFS+AUTHCONFIG+AUTOFS实现自动挂载NIS宿主目录到客户机
3.selinux
 
实验目的：
1。将sdb，sdc,sdd3块硬盘组成raid5模式
2。建立LVM
3。模拟故障，sdc出故障，删除该硬盘，再重新添加硬盘，恢复raid5
4。增加LVM容量
实验步骤
1，格式化3块硬盘
[root@RHEL5-1 ~]# fdisk /dev/sdb  //格式化/dev/sdb
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel. 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)
Command (m for help): n  //增加一个新的分区
Command action
   e   extended
   p   primary partition (1-4)
p  //创建主分区
Partition number (1-4): 1 //分区号为1
First cylinder (1-130, default 1):  //设置分区大小
Using default value 1
Last cylinder or +size or +sizeM or +sizeK (1-130, default 130):
Using default value 130
Command (m for help): t   //改变系统的ID
Selected partition 1
Hex code (type L to list codes): fd  //设置系统HEX为fd，即raid模式
Changed system type of partition 1 to fd (Linux raid autodetect)
Command (m for help): w  //保存
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
[root@RHEL5-1 ~]# fdisk /dev/sdc //格式化/dev/sdc
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel. 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)
Command (m for help): n
Command action
   e   extended
   p   primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-130, default 1):
Using default value 1
Last cylinder or +size or +sizeM or +sizeK (1-130, default 130):
Using default value 130
Command (m for help): t
Selected partition 1
Hex code (type L to list codes): fd
Changed system type of partition 1 to fd (Linux raid autodetect)
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
[root@RHEL5-1 ~]# fdisk /dev/sdd  //格式化/dev/sdd
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel. 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)
Command (m for help): n
Command action
   e   extended
   p   primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-130, default 1):
Using default value 1
Last cylinder or +size or +sizeM or +sizeK (1-130, default 130):
Using default value 130
Command (m for help): t
Selected partition 1
Hex code (type L to list codes): fd
Changed system type of partition 1 to fd (Linux raid autodetect)
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
[root@RHEL5-1 ~]# fdisk -l  //查看分区情况
Disk /dev/sda: 8589 MB, 8589934592 bytes
255 heads, 63 sectors/track, 1044 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1          13      104391   83  Linux
/dev/sda2              14         268     2048287+  83  Linux
/dev/sda3             269         395     1020127+  83  Linux
/dev/sda4             396        1044     5213092+   5  Extended
/dev/sda5             396         522     1020096   82  Linux swap / Solaris
/dev/sda6             523        1044     4192933+  83  Linux
Disk /dev/sdb: 1073 MB, 1073741824 bytes
255 heads, 63 sectors/track, 130 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1         130     1044193+  fd  Linux raid autodetect
Disk /dev/sdc: 1073 MB, 1073741824 bytes
255 heads, 63 sectors/track, 130 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1               1         130     1044193+  fd  Linux raid autodetect
Disk /dev/sdd: 1073 MB, 1073741824 bytes
255 heads, 63 sectors/track, 130 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
   Device Boot      Start         End      Blocks   Id  System
/dev/sdd1               1         130     1044193+  fd  Linux raid autodetect
 建立raid5
[root@RHEL5-1 ~]# mdadm --create /dev/md0 --level=5 --raid-device=3 /dev/sdb1 /d
ev/sdc1 /dev/sdd1  //创建raid5，/dev/md0阵列设备名，level=5阵列模式raid5，raid-device=3raid有3块硬盘
mdadm: array /dev/md0 started.
[root@RHEL5-1 ~]# cat /proc/mdstat  //查看数据同步情况
Personalities : [raid6] [raid5] [raid4]
md0 : active raid5 sdd1[3] sdc1[1] sdb1[0]
      2088192 blocks level 5, 64k chunk, algorithm 2 [3/2] [UU_]
      [========>............]  recovery = 40.0% (419060/1044096) finish=1.4min speed=7423K/sec
unused devices: <none>
[root@RHEL5-1 ~]# cat /proc/mdstat   //看到这个说明同步结束
Personalities : [raid6] [raid5] [raid4]
md0 : active raid5 sdd1[2] sdc1[1] sdb1[0]
      2088192 blocks level 5, 64k chunk, algorithm 2 [3/3] [UUU]
unused devices: <none>
[root@RHEL5-1 ~]# tail /var/log/messages  //查看系统日志
Jun  1 11:34:10 RHEL5-1 kernel: md: syncing RAID array md0
Jun  1 11:34:13 RHEL5-1 kernel: md: minimum _guaranteed_ reconstruction speed: 1000 KB/sec/disc.
Jun  1 11:34:15 RHEL5-1 kernel: md: using maximum available idle IO bandwidth (but not more than 200000 KB/sec) for reconstruction.
Jun  1 11:34:19 RHEL5-1 kernel: md: using 128k window, over a total of 1044096 blocks.
Jun  1 11:36:01 RHEL5-1 kernel: md: md0: sync done.
Jun  1 11:36:01 RHEL5-1 kernel: RAID5 conf printout:
Jun  1 11:36:01 RHEL5-1 kernel:  --- rd:3 wd:3 fd:0
Jun  1 11:36:01 RHEL5-1 kernel:  disk 0, o:1, dev:sdb1
Jun  1 11:36:01 RHEL5-1 kernel:  disk 1, o:1, dev:sdc1
Jun  1 11:36:01 RHEL5-1 kernel:  disk 2, o:1, dev:sdd1
建立raid5的配置文件
[root@RHEL5-1 ~]# echo device /dev/sdb1 /dev/sdc1 /dev/sdd1 &gt; /etc/mdadm.conf
[root@RHEL5-1 ~]# mdadm --detail --scan >> /etc/mdadm.conf
[root@RHEL5-1 ~]# cat /etc/mdadm.conf
device /dev/sdb1 /dev/sdc1 /dev/sdd1
ARRAY /dev/md0 level=raid5 num-devices=3 UUID=36f261b7:4899a54c:9edf36d1:9eb86529
[root@RHEL5-1 ~]# mdadm -S /dev/md0  //停止阵列
mdadm: stopped /dev/md0
[root@RHEL5-1 ~]# mdadm -As /dev/md0  //启动阵列
mdadm: /dev/md0 has been started with 3 drives.
2 建立LVM
[root@RHEL5-1 ~]# pvcreate /dev/md0 //建立PV
  Physical volume "/dev/md0" successfully created
[root@RHEL5-1 ~]# vgcreate lvm1 /dev/md0  //建立VG
  Volume group "lvm1" successfully created
[root@RHEL5-1 ~]# vgdisplay  //查看VG
  --- Volume group ---
  VG Name               lvm1
  System ID            
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  1
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                0
  Open LV               0
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               1.99 GB
  PE Size               4.00 MB
  Total PE              509
  Alloc PE / Size       0 / 0  
  Free  PE / Size       509 / 1.99 GB
  VG UUID               h7d74U-S38z-rQrw-ecGG-ePlg-48b5-87sbC1
[root@RHEL5-1 ~]# lvcreate -L 500m -n web1 lvm1 //建立LV ，名为web1，大小为500M
  Logical volume "web1" created
[root@RHEL5-1 ~]# lvcreate -L 500m -n web2 lvm1  //建立LV ，名为web2，大小为500M
Logical volume "web2" created
[root@RHEL5-1 ~]# mke2fs -j /dev/lvm1/web1  //格式化web1
mke2fs 1.39 (29-May-2006)
Filesystem label=
OS type: Linux
Block size=1024 (log=0)
Fragment size=1024 (log=0)
128016 inodes, 512000 blocks
25600 blocks (5.00%) reserved for the super user
First data block=1
Maximum filesystem blocks=67633152
63 block groups
8192 blocks per group, 8192 fragments per group
2032 inodes per group
Superblock backups stored on blocks:
        8193, 24577, 40961, 57345, 73729, 204801, 221185, 401409
Writing inode tables: done                           
Creating journal (8192 blocks): done
Writing superblocks and filesystem accounting information: done
This filesystem will be automatically checked every 26 mounts or
180 days, whichever comes first.  Use tune2fs -c or -i to override.
[root@RHEL5-1 ~]# mke2fs -j /dev/lvm1/web2  //格式化web1
mke2fs 1.39 (29-May-2006)
Filesystem label=
OS type: Linux
Block size=1024 (log=0)
Fragment size=1024 (log=0)
128016 inodes, 512000 blocks
25600 blocks (5.00%) reserved for the super user
First data block=1
Maximum filesystem blocks=67633152
63 block groups
8192 blocks per group, 8192 fragments per group
2032 inodes per group
Superblock backups stored on blocks:
        8193, 24577, 40961, 57345, 73729, 204801, 221185, 401409
Writing inode tables: done                           
Creating journal (8192 blocks): done
Writing superblocks and filesystem accounting information: done
This filesystem will be automatically checked every 39 mounts or
180 days, whichever comes first.  Use tune2fs -c or -i to override.
[root@RHEL5-1 ~]# mkdir /web1
[root@RHEL5-1 ~]# mkdir /web2
[root@RHEL5-1 ~]# mount /dev/lvm1/web1 /web1    //挂载
[root@RHEL5-1 ~]# mount /dev/lvm1/web2 /web2
[root@RHEL5-1 ~]# vi /etc/fstab  //编辑/etc/fstab，让系统启动时自动挂载
LABEL=/                 /                       ext3    defaults        1 1
LABEL=/var              /var                    ext3    defaults        1 2
LABEL=/tmp              /tmp                    ext3    defaults        1 2
LABEL=/boot             /boot                   ext3    defaults        1 2
tmpfs                   /dev/shm                tmpfs   defaults        0 0
devpts                  /dev/pts                devpts  gid=5,mode=620  0 0
sysfs                   /sys                    sysfs   defaults        0 0
proc                    /proc                   proc    defaults        0 0
LABEL=SWAP-sda5         swap                    swap    defaults        0 0
/dev/lvm1/web1          /web1                   ext3    defaults        0 0
/dev/lvm1/web2          /web2                   ext3    defaults        0 0
[root@RHEL5-1 ~]# reboot
查看/web1的容量
[root@RHEL5-1 ~]# df -h /web1
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/lvm1-web1
                      485M   11M  449M   3% /web1
[root@RHEL5-1 ~]# pvdisplay
  --- Physical volume ---
  PV Name               /dev/md0
  VG Name               lvm1
  PV Size               1.99 GB / not usable 3.25 MB
  Allocatable           yes
  PE Size (KByte)       4096
  Total PE              509
  Free PE               259
  Allocated PE          250
  PV UUID               HSyAfx-Qxdv-b6id-01sZ-eRVC-HWAj-By3ctA
3模拟故障
[root@RHEL5-1 ~]# mdadm /dev/md0 -f /dev/sdc1  //标记/dev/sdc1为故障盘
mdadm: set /dev/sdc1 faulty in /dev/md0
[root@RHEL5-1 ~]# more /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md0 : active raid5 sdd1[2] sdc1[3](F) sdb1[0]     //[F]表示为故障盘
      2088192 blocks level 5, 64k chunk, algorithm 2 [3/2] [U_U]
unused devices: <none>
[root@RHEL5-1 ~]# mdadm /dev/md0 -r /dev/sdc1   //移除故障盘
mdadm: hot removed /dev/sdc1
[root@RHEL5-1 ~]# more /proc/mdstat    //查看阵列情况
Personalities : [raid6] [raid5] [raid4]
md0 : active raid5 sdd1[2] sdb1[0]
      2088192 blocks level 5, 64k chunk, algorithm 2 [3/2] [U_U]
unused devices: <none>
[root@RHEL5-1 ~]# pvdisplay /dev/md0   //查看PV情况，发现容量没减少
  --- Physical volume ---
  PV Name               /dev/md0
  VG Name               lvm1
  PV Size               1.99 GB / not usable 3.25 MB
  Allocatable           yes
  PE Size (KByte)       4096
  Total PE              509
  Free PE               259
  Allocated PE          250
  PV UUID               HSyAfx-Qxdv-b6id-01sZ-eRVC-HWAj-By3ctA
[root@RHEL5-1 ~]# fdisk /dev/sdc   //重新格式化sdc，重新添加进阵列
Command (m for help): n
Command action
   e   extended
   p   primary partition (1-4)
p
Partition number (1-4): 1
Partition 1 is already defined.  Delete it before re-adding it.
Command (m for help): t
Selected partition 1
Hex code (type L to list codes): fd
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
[root@RHEL5-1 ~]# mdadm /dev/md0 -a /dev/sdc1   //增加
mdadm: re-added /dev/sdc1
[root@RHEL5-1 ~]# more /proc/mdstat    //开始同步数据
Personalities : [raid6] [raid5] [raid4]  
md0 : active raid5 sdc1[1] sdd1[2] sdb1[0]
      2088192 blocks level 5, 64k chunk, algorithm 2 [3/2] [U_U]
      [==&gt;..................]  recovery = 12.2% (128796/1044096) finish=2.1min s
peed=7155K/sec
unused devices: <none>
[root@RHEL5-1 ~]# pvdisplay
  --- Physical volume ---
  PV Name               /dev/md0
  VG Name               lvm1
  PV Size               1.99 GB / not usable 3.25 MB
  Allocatable           yes
  PE Size (KByte)       4096
  Total PE              509
  Free PE               259
  Allocated PE          250
  PV UUID               HSyAfx-Qxdv-b6id-01sZ-eRVC-HWAj-By3ctA
[root@RHEL5-1 ~]# vgdisplay lvm1
  --- Volume group ---
  VG Name               lvm1
  System ID            
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  3
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                2
  Open LV               2
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               1.99 GB
  PE Size               4.00 MB
  Total PE              509
  Alloc PE / Size       250 / 1000.00 MB
  Free  PE / Size       259 / 1.01 GB
  VG UUID               h7d74U-S38z-rQrw-ecGG-ePlg-48b5-87sbC1
[root@RHEL5-1 ~]# df -h /web1
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/lvm1-web1
                      485M   11M  449M   3% /web1
4。增加LVM容量
[root@RHEL5-1 ~]# lvextend -L +50M /dev/lvm1/web1   //增加web1 50M
  Rounding up size to full physical extent 52.00 MB
  Extending logical volume web1 to 552.00 MB
  Logical volume web1 successfully resized
[root@RHEL5-1 ~]# resize2fs /dev/lvm1/web1   //刷新
resize2fs 1.39 (29-May-2006)
Filesystem at /dev/lvm1/web1 is mounted on /web1; on-line resizing required
Performing an on-line resize of /dev/lvm1/web1 to 565248 (1k) blocks.
The filesystem on /dev/lvm1/web1 is now 565248 blocks long.

[root@RHEL5-1 ~]# df -h /web1   //查看
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/lvm1-web1

NIS+NFS+AUTHCONFIG+AUTOFS实现自动挂载NIS宿主目录到客户机

一、在NIS服务器上共享NIS用户主目录

1.创建用户及NIS用户主目录

建议在NIS服务器上建立独立的目录存放NIS帐号信息，如果保持默认设置则客户端挂载NIS主目录到/home目录时会覆盖原有用户主目录而导致其他异常错误；

我们现在建立/nishome存放NIS用户的主目录并使用useradd -d将NIS帐号的主目录指向/nishome,如果己有帐号可以使用usermod -d变更主目录。

  1. [root@master /]# mkdir nishome
  2. [root@master /]# mkdir nishome/nisuser1
  3. [root@master /]# usermod -d /nishome/nisuser1/ nisuser1
  4. [root@master /]# useradd -d /nishome/nisuser2 nisuser2
  5. [root@master /]# ls nishome/
  6. nisuser1 nisuser2

2.重新生成NIS数据库并重启ypserv和yppasswd服务

# /usr/lib/yp/ypinit -m

# service ypserv restart

# service yppasswdd restart

3.共享用户主目录

  1. # vim /etc/exports
  2. /nishome/nisuser1 *(rw)
  3. /nishome/nisuser2 *(rw)

4.重启NFS服务

  1. [root@master /]# service nfs restart
  2. Shutting down NFS mountd: [ OK ]
  3. Shutting down NFS daemon: [ OK ]
  4. Shutting down NFS quotas: [ OK ]
  5. Shutting down NFS services: [ OK ]
  6. Starting NFS services: [ OK ]
  7. Starting NFS quotas: [ OK ]
  8. Starting NFS daemon: [ OK ]
  9. Starting NFS mountd: [ OK ]
  10. Stopping RPC idmapd: [ OK ]
  11. Starting RPC idmapd: [ OK ]

二、客户端配置NIS验证及Autofs

1.检测主/从NIS服务器相应服务是否正常开启

  1. [root@client01 ~]# rpcinfo -p master.abcnis
  2.    program vers proto port
  3.     100000 2 tcp 111 portmapper
  4.     100000 2 udp 111 portmapper
  5.     100024 1 udp 952 status
  6.     100024 1 tcp 955 status
  7.     100004 2 udp 682 ypserv
  8.     100004 1 udp 682 ypserv
  9.     100004 2 tcp 685 ypserv
  10.     100004 1 tcp 685 ypserv
  11.     100009 1 udp 699 yppasswdd
  12.     100011 1 udp 781 rquotad
  13.     100011 2 udp 781 rquotad
  14.     100011 1 tcp 784 rquotad
  15.     100011 2 tcp 784 rquotad
  16.     100003 2 udp 2049 nfs
  17.     100003 3 udp 2049 nfs
  18.     100003 4 udp 2049 nfs
  19.     100021 1 udp 49642 nlockmgr
  20.     100021 3 udp 49642 nlockmgr
  21.     100021 4 udp 49642 nlockmgr
  22.     100003 2 tcp 2049 nfs
  23.     100003 3 tcp 2049 nfs
  24.     100003 4 tcp 2049 nfs
  25.     100021 1 tcp 57392 nlockmgr
  26.     100021 3 tcp 57392 nlockmgr
  27.     100021 4 tcp 57392 nlockmgr
  28.     100005 1 udp 796 mountd
  29.     100005 1 tcp 799 mountd
  30.     100005 2 udp 796 mountd
  31.     100005 2 tcp 799 mountd
  32.     100005 3 udp 796 mountd
  33.     100005 3 tcp 799 mountd

2.Authconfig启用NIS验证
执行setup（或者authconfig-tui命令）




3.修改Autofs主配置文件

  1. vim /etc/auto.master
  2. # Sample auto.master file
  3. # This is an automounter map and it has the following format
  4. # key [ -mount-options-separated-by-comma ] location
  5. # For details of the format look at autofs(5).
  6. #/misc   /etc/auto.misc
  7. # NOTE: mounts done from a hosts map will be mounted with the
  8. #       "nosuid" and "nodev" options unless the "suid" and "dev"
  9. #       options are explicitly given.
  10. #
  11. /net    -hosts
  12. /nishome        /etc/auto.nishome      
  13. #nishome是客户端要挂载的目录；auto.nishome是Autofs客户端配置文件；
  14. # Include central master map if it can be found using
  15. # nsswitch sources.
  16. # Note that if there are entries for /net or /misc (as
  17. # above) in the included master map any keys that are th
  18. # same will not be seen as the first read key seen takes
  19. # precedence.
  20. +auto.master

4.创建NIS自动挂载配置文件

  1. [root@client01 ~]# touch /etc/auto.nishome

  3. [root@client01 ~]# vim /etc/auto.nishome
  4. * -fstype=nfs master.abcnis:/nishome/&
  5. # Autofs挂载目录支持通配符 * ；
  6. # 网络路径中的用户名使用 & 表示；

5.重启Autofs服务
# service autofs restart
可以看到重启Autofs服务后客户端自动创建了/nishome目录！

三、客户端测试
注意如果使用su命令在NIS客户端切换到NIS用户时，在第一次可能会报无法定位到用户家目录的错误，没有关系，退出第二次再使用时就会正常。

  1. [root@client01 ~]# su nisuser1
  2. [nisuser1@client01 root]$ pwd
  3. /root
  4. [nisuser1@client01 root]$ cd
  5. [nisuser1@client01 nisuser1]$ pwd
  6. /nishome/nisuser1
  7. [nisuser1@client01 nisuser1]$

    selinux

关闭防火墙

SELINUX=disabled

可以是三种状态

# enforcing - SELinux security policy is enforced.打开
# permissive - SELinux prints warnings instead of enforcing.打开不拦截
# disabled - No SELinux policy is loaded.关闭，默认

selinux在打开状态下，可以使用下面两个命令

第一个命令是查询selinux的状态，处于关闭状态。

第二个命令是临时关闭。

第三个命令是临时打开。

永久打开或关闭就修改上面的那个配置文件。vim /etc/selinux/config

重启生效。

也可以临时打开或关闭，下次开机就生效了。

////////////////////////////////////////////////////////////////////////////////////////////

总结：如果了解selinux就打开，否则关闭。。

【推广】 免费学中医，健康全家人
原文地址：https://www.cnblogs.com/cityinthesky/p/5771717.html