硬盘分区管理大容量的硬盘分区使用C盘系统盘D盘办公E盘娱乐。类似于买了一个房子100平方隔断主卧、次卧1、次卧2、厨房、卫生间。识别硬盘设备接口类型设备命名示例说明SATA/SAS/USB/SCSI/dev/sda、/dev/sdb…物理机常用的磁盘设备命名virtio-blk虚拟机/dev/vda、/dev/vdb…KVM 虚拟机常用磁盘命名NVMe SSD/dev/nvme0n1、/dev/nvme1n1…高性能 NVMe 固态硬盘命名SD/MMC/eMMC/dev/mmcblk0、/dev/mmcblk1…嵌入式设备常用存储命名虚拟机添加2个硬盘sata 接口20GNVMe接口40G关机添加# 查看块block设备清单[rootcentos7 ~ 09:45:14]# lsblkNAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda8:00200G0disk ├─sda18:101G0part /boot#sda 硬盘的第一个分区└─sda28:20199G0part ├─centos-root253:0050G0lvm / ├─centos-swap253:102G0lvm[SWAP]└─centos-home253:20147G0lvm /home sdb8:16020G0disk# 新增的sata硬盘sr011:014.4G0rom nvme0n1259:0040G0disk# 新增的NVMe硬盘设备类型块设备b大部分情况下都是存储设备例如光盘、硬盘、U盘。字符设备c一般是输入和输出设备例如终端设备tty1、vty、pst/0等硬盘分区方案直接管理主板上外接设备的系统称之为固件。例如调整设备启动顺序光盘作为第一启动项用来安装系统。分区方案MBR自1982年起主启动记录MBR分区方案成为运行BIOS 固件系统的磁盘分区标准。主分区数量限制最多支持4个主分区。扩展分区与逻辑分区Linux 系统中可通过“主分区扩展分区”的方式突破主分区限制扩展分区仅作为逻辑分区的“容器”不可格式化逻辑分区可格式化使用整体最多可创建15个分区。容量限制MBR 用4个字节存储分区总扇区数按单扇区512字节计算单个分区最大容量不超过2 TiB。GPT全局唯一标识分区表GPT是运行统一可扩展固件接口UEFI系统的磁盘分区标准。容量支持使用8个字节存储分区总扇区数单分区/磁盘最大支持18 ZiB18亿 TiB完全满足大磁盘需求。分区数量默认支持128个分区无需扩展分区/逻辑分区实际使用中建议不超过120个避免格式化异常。数据冗余GPT 分区表包含主表和备份表且自带 CRC32 校验码可自动检测并恢复损坏的分区表。fdisk 管理 MBRfdisk 管理 MBR新版本的fdisk也可以用来管理GPT。查看硬盘信息# 查看所有块设备进一步过滤出sd相关设备[rootcentos7 ~ 08:19:43]# fdisk -l | grep sdDisk /dev/sda:214.7GB,214748364800bytes,419430400sectors /dev/sda1 *20482099199104857683Linux /dev/sda220992004194303992086656008e Linux LVM Disk /dev/sdb:21.5GB,21474836480bytes,41943040sectors# 查看特定硬盘信息[rootcentos7 ~ 08:21:43]# fdisk -l /dev/sdaDisk /dev/sda:214.7GB,214748364800bytes,419430400sectors Unitssectors of1*512512bytes Sector size(logical/physical):512bytes /512bytes I/O size(minimum/optimal):512bytes /512bytes Disk label type: dos# MBR分区格式Disk identifier: 0x000bd48e Device Boot Start End Blocks Id System /dev/sda1 *20482099199104857683Linux /dev/sda220992004194303992086656008e Linux LVM# sdb 硬盘没有分区[rootcentos7 ~ 08:21:50]# fdisk -l /dev/sdbDisk /dev/sdb:21.5GB,21474836480bytes,41943040sectors Unitssectors of1*512512bytes Sector size(logical/physical):512bytes /512bytes I/O size(minimum/optimal):512bytes /512bytes帮助信息# 交互方式管理sdb硬盘[rootcentos7 ~ 08:21:53]# fdisk /dev/sdbWelcome tofdisk(util-linux2.23.2). Changes will remaininmemory only,untilyou decide towritethem. Be careful before using thewritecommand. Device does not contain a recognized partition table Building a new DOS disklabel with disk identifier 0xdfdac101.# m 查看帮助Command(mforhelp):mCommand 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 nadda new partition o create a new empty DOS partition table p print the partition table q quit without saving changes s create a new empty Sun disklabel t change a partitions systemidu change display/entryunitsvverify the partition table wwritetable to disk andexitx extra functionality(experts only)查看分区表# p 查看分区表Command(mforhelp):pDisk /dev/sdb:21.5GB,21474836480bytes,41943040sectors Unitssectors of1*512512bytes Sector size(logical/physical):512bytes /512bytes I/O size(minimum/optimal):512bytes /512bytes Disk label type: dos Disk identifier: 0xdfdac101 Device Boot Start End Blocks Id System# sdb硬盘是空盘没有分区创建分区# n 新建分区Command(mforhelp):nPartition type: p primary(0primary,0extended,4free)e extended Select(default p):回车# 主分区类型Using default response p Partition number(1-4, default1):回车# 分区号First sector(2048-41943039, default2048):回车# 分区的起始位置Using default value2048Last sector, sectors or size{K,M,G}(2048-41943039, default41943039):5G# 分区的结束位置Partition1oftypeLinux and of size5GiB isset# 再次查看多了一个分区Command(mforhelp):pDisk /dev/sdb:21.5GB,21474836480bytes,41943040sectors Unitssectors of1*512512bytes Sector size(logical/physical):512bytes /512bytes I/O size(minimum/optimal):512bytes /512bytes Disk label type: dos Disk identifier: 0xdfdac101 Device Boot Start End Blocks Id System /dev/sdb1204810487807524288083Linux保存分区表# w 保存修改Command(mforhelp):wThe partition table has been altered!Calling ioctl()to re-read partition table. Syncing disks.# 再次查看块设备[rootcentos7 ~ 08:29:58]# lsblk /dev/sdbNAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sdb8:16020G0disk └─sdb18:1705G0part删除分区[rootcentos7 ~ 08:30:05]# fdisk /dev/sdbWelcome tofdisk(util-linux2.23.2). Changes will remaininmemory only,untilyou decide towritethem. Be careful before using thewritecommand.# d 删除分区Command(mforhelp):dSelected partition1Partition1is deleted Command(mforhelp):pDisk /dev/sdb:21.5GB,21474836480bytes,41943040sectors Unitssectors of1*512512bytes Sector size(logical/physical):512bytes /512bytes I/O size(minimum/optimal):512bytes /512bytes Disk label type: dos Disk identifier: 0xdfdac101 Device Boot Start End Blocks Id System# 对应的分区被删除# 保存退出Command(mforhelp):wThe partition table has been altered!Calling ioctl()to re-read partition table. Syncing disks.计算机存储单位。GB1000MBGiB1024MiBgdisk 工具gdisk 工具用于管理 GPT 分区方案的硬盘。# 安装工具[rootcentos7 ~ 08:47:43]# yum install -y gdisk查看硬盘信息[rootcentos7 ~ 08:47:53]# gdisk -l /dev/sdbGPTfdisk(gdisk)version0.8.10 Partition table scan: MBR: MBR only# MBR 管理方案BSD: not present APM: not present GPT: not present *************************************************************** Found invalid GPT and valid MBR;converting MBR to GPTformatinmemory. *************************************************************** Disk /dev/sdb:41943040sectors,20.0GiB Logical sector size:512bytes Disk identifier(GUID): 338C66BF-D237-43A9-8551-4C038013BAD5 Partition table holds up to128entries First usable sector is34, last usable sector is41943006Partitions will be aligned on2048-sector boundaries Totalfreespace is41942973sectors(20.0GiB)Number Start(sector)End(sector)Size Code Name帮助信息[rootcentos7 ~ 08:48:20]# gdisk /dev/sdbGPTfdisk(gdisk)version0.8.10 Partition table scan: MBR: MBR only BSD: not present APM: not present GPT: not present *************************************************************** Found invalid GPT and valid MBR;converting MBR to GPTformatinmemory. THIS OPERATION IS POTENTIALLY DESTRUCTIVE!Exit by typingqifyou dont want to convert your MBR partitions to GPT format! *************************************************************** Command (? for help): ? b back up GPT data to a file # 备份GPT数据到文件 c change a partitions name# 修改分区名称d delete a partition# 删除分区i show detailed information on a partition# 查看分区详细信息l list known partition types# 列出已知分区类型nadda new partition# 创建新分区o create a new empty GUID partition table(GPT)# 创建空GPT分区表p print the partition table# 打印分区表q quit without saving changes# 退出不保存r recovery and transformation options(experts only)# 恢复/转换选项专家模式ssortpartitions# 排序分区t change a partitionstypecode# 修改分区类型码vverify disk# 校验磁盘wwritetable to disk andexit# 保存并退出x extra functionality(experts only)# 扩展功能专家模式? print this menu# 打印帮助菜单查看分区表Command(?forhelp): p Disk /dev/sdb:41943040sectors,20.0GiB Logical sector size:512bytes Disk identifier(GUID): 7EAD059D-101E-4C4F-A263-B30CF8B6FD42 Partition table holds up to128entries First usable sector is34, last usable sector is41943006Partitions will be aligned on2048-sector boundaries Totalfreespace is41942973sectors(20.0GiB)Number Start(sector)End(sector)Size Code Name创建分区Command(?forhelp): n Partition number(1-128, default1): First sector(34-41943006, default2048)or{-}size{KMGTP}: Last sector(2048-41943006, default41943006)or{-}size{KMGTP}: 10G CurrenttypeisLinux filesystemHex code or GUID(L to show codes, Enter8300):回车# 分区也是有类型例如lvm表明分区的用途Changedtypeof partition toLinux filesystemCommand(?forhelp): p Disk /dev/sdb:41943040sectors,20.0GiB Logical sector size:512bytes Disk identifier(GUID): 7EAD059D-101E-4C4F-A263-B30CF8B6FD42 Partition table holds up to128entries First usable sector is34, last usable sector is41943006Partitions will be aligned on2048-sector boundaries Totalfreespace is20971453sectors(10.0GiB)Number Start(sector)End(sector)Size Code Name120482097356710.0GiB8300Linux filesystem保存分区表Command(?forhelp): w Final checks complete. About towriteGPT data. THIS WILL OVERWRITE EXISTING PARTITIONS!!Do you want to proceed?(Y/N): Y OK;writing new GUID partition table(GPT)to /dev/sdb. The operation has completed successfully.# 再次查看[rootcentos7 ~ 08:53:39]# lsblk /dev/sdbNAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sdb8:16020G0disk └─sdb18:17010G0part删除分区[rootcentos7 ~ 08:53:59]# gdisk /dev/sdbGPTfdisk(gdisk)version0.8.10 Partition table scan: MBR: protective# 保护式MBR属于GPT的一部分BSD: not present APM: not present GPT: present# GPT 格式Found valid GPT with protective MBR;using GPT. Command(?forhelp): p Disk /dev/sdb:41943040sectors,20.0GiB Logical sector size:512bytes Disk identifier(GUID): 7EAD059D-101E-4C4F-A263-B30CF8B6FD42 Partition table holds up to128entries First usable sector is34, last usable sector is41943006Partitions will be aligned on2048-sector boundaries Totalfreespace is20971453sectors(10.0GiB)Number Start(sector)End(sector)Size Code Name120482097356710.0GiB8300Linux filesystem# d 删除Command(?forhelp): d Using1# 再次确认Command(?forhelp): p Disk /dev/sdb:41943040sectors,20.0GiB Logical sector size:512bytes Disk identifier(GUID): 7EAD059D-101E-4C4F-A263-B30CF8B6FD42 Partition table holds up to128entries First usable sector is34, last usable sector is41943006Partitions will be aligned on2048-sector boundaries Totalfreespace is41942973sectors(20.0GiB)Number Start(sector)End(sector)Size Code Name# 保存退出Command(?forhelp): w Final checks complete. About towriteGPT data. THIS WILL OVERWRITE EXISTING PARTITIONS!!Do you want to proceed?(Y/N): Y OK;writing new GUID partition table(GPT)to /dev/sdb. The operation has completed successfully.# 再次查看[rootcentos7 ~ 08:53:39]# lsblk /dev/sdbNAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sdb8:16020G0disk