硬盘类型
1、SATA民用:不支持热插拔;
2、SCSI、SAS企业用:支持热插拔;
MBR分区方案
此方案最多支持4个主分区,在linux可以将第4个主分区设置为扩展分区(扩展分区只是表示分区范围,并不是实际的分区,无意义),在扩展分区下建立逻辑分区最多15个分区;2T以上硬盘不在支持MBR。
GPT分区方案
默认支持128个分区;可以解决MBR大小的限制;
GPT提供分区表信息冗余;主GPT在头,副本备份在尾;
fdisk管理MBR分区磁盘
1、硬盘分区表建立
#fdisk -l //显示磁盘信息
#fdisk /dev/sdb
Welcome to fdisk (util-linux 2.23.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Device does not contain a recognized partition table
Building a new DOS disklabel with disk identifier 0xdebdcc37.
Command (m for help): //m获得帮助
Command action
a toggle a bootable flag
b edit bsd disklabel
c toggle the dos compatibility flag
d delete a partition
g create a new empty GPT partition table
G create an IRIX (SGI) partition table
l list known partition types
m print this menu
n add a new partition
o create a new empty DOS partition table
p print the partition table //打印分区表
q quit without saving changes
s create a new empty Sun disklabel
t change a partition's system id
u change display/entry units
v verify the partition table
w write table to disk and exit //保存分区信息
x extra functionality (experts only)
Command (m for help): n //新建
Partition type:
p primary (0 primary, 0 extended, 4 free) //新建sdb第二块磁盘的主分区
e extended //新建扩展分区
Select (default p): p
Partition number (1-4, default 1): //默认编号1
First sector (2048-4194303, default 2048): //默认起始扇区
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-4194303, default 4194303): +1G //新建1g主分区
Partition 1 of type Linux and of size 1 GiB is set
#partprobe /dev/sdb //刷新硬盘分区表
#ls /dev/sdb<tab> //列出分区表
2、分区格式化
制作文件系统格式,格式化后产生唯一uuid;
#mkfs.xfs /dev/sdb1 //格式化为xfs
#blkid /dev/sdb1 //获取sdb1的uuid
3、硬盘分区自动挂载(持久化)
#blkid /dev/sdb1 >> /etc/fstab //将uuid写入 fstab
#vim /etc/fstab
uuid=" " /mnt/xfs(挂载点) xfs(类型) default 0(不检查) 0(不备份)
#mkdir /mnt/xfs //建立挂载点目录
#mount -a //重新获取挂载点
#df -h //查看挂载点
// umount /dev/sda1 取消挂载
gdisk管理GPT分区
#gdisk /dev/sdb
GPT fdisk (gdisk) version 0.8.6
Partition table scan:
MBR: not present
BSD: not present
APM: not present
GPT: not present
Creating new GPT entries.
Command (? for help): ?
b back up GPT data to a file
c change a partition's name
d delete a partition
i show detailed information on a partition
l list known partition types
n add a new partition
o create a new empty GUID partition table (GPT)
p print the partition table
q quit without saving changes
r recovery and transformation options (experts only)
s sort partitions
t change a partition's type code
v verify disk
w write table to disk and exit
x extra functionality (experts only)
? print this menu
管理交换空间
交换空间可与linux内核内存配合使用的磁盘区域;补充系统的RAM,合成虚拟内存。
1、新建交换分区
#fdisk /dev/vdb
n l +500M
#partprobe /dev/vdb
2、交换分区格式化
#mkswap /dev/vdb6
3、交换分区持久化挂载
#blkid /dev/vdb6 >> /etc/fstab
#vim /etc/fstab
uuid=" " swap swap default 0 0
//或者 /dev/vdb6 swap swap defaults 0 0
#swapon -a //开启swap -s查看
#swapoff /dev/vdb6 //停止 删除fstab 删除分区
磁盘配额
为特定用户限制使用磁盘空间;
以下为格式ext的设置。
#vim /etc/fstab
uuid=" " ext4 default,usrquota 0 0
#mount -o remount /dev/vdb1 //重新加载
#quotacheck -cuf /dev/vdb1 /mnt/ext //强制生成用户数据库
#quotaon /dev/vdb1 //开启
#edquota -u wode //设置用户的空间大小
#chmod o+w ext/
(wode)#cd /mnt/ext
#dd if=/etc/zero of=aaa bs=1k count=10 //测试命令
RAID磁盘冗余阵列
解决磁盘损坏,数据无法写入和丢失;
软RAID:os内核提供cpu运算;
硬RAID(企业):自带阵列卡(cpu、内存)、有接口接硬盘;
RAID命令配置
软RAID5(利用软件mdadm):新建三块磁盘
#mdadm --create /dev/md0 --level=5 --raid-devices=3 /dev/vdb{6,7,8} //3个磁盘设置为raid5
#mkfs.xfs /dev/md0 //3磁盘格式化为xfs
#blkid /dev/md0 >> /etc/fstab
#vim /etc/fstab
uuid= xfs /mnt/raid default 0 0 //设置挂载点
#mkdir /mnt/raid
#mount -a
#mdadm --detail --scan > /etc/mdadm.conf //生成配置文件
#mdadm --detail /dev/md0 //查看状态
测试
#mdadm /dev/md0 --set-faulty /dev/vdb7
#mdadm /dev/md0 --remove (--add)/dev/vdb7