How to resize root partition on Linux Redhat 7 without restart

[root@devsim ~]# fdisk /dev/sda

The device presents a logical sector size that is smaller than
the physical sector size. Aligning to a physical sector (or optimal
I/O) size boundary is recommended, or performance may be impacted.
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.


Command (m for help): m
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
   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
   x   extra functionality (experts only)

Command (m for help): p

Disk /dev/sda: 322.1 GB, 322122547200 bytes, 629145600 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 1048576 bytes
Disk label type: dos
Disk identifier: 0x000c57d5

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048     2099199     1048576   83  Linux
/dev/sda2         2099200   314572799   156236800   8e  Linux LVM

Command (m for help): n
Partition type:
   p   primary (2 primary, 0 extended, 2 free)
   e   extended
Select (default p): p
Partition number (3,4, default 3):
First sector (314572800-629145599, default 314572800):
Using default value 314572800
Last sector, +sectors or +size{K,M,G} (314572800-629145599, default 629145599):
Using default value 629145599
Partition 3 of type Linux and of size 150 GiB is set

Command (m for help): p

Disk /dev/sda: 322.1 GB, 322122547200 bytes, 629145600 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 1048576 bytes
Disk label type: dos
Disk identifier: 0x000c57d5

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048     2099199     1048576   83  Linux
/dev/sda2         2099200   314572799   156236800   8e  Linux LVM
/dev/sda3       314572800   629145599   157286400   83  Linux

Command (m for help): t
Partition number (1-3, default 3): 3
Hex code (type L to list all codes): L

 0  Empty           24  NEC DOS         81  Minix / old Lin bf  Solaris
 1  FAT12           27  Hidden NTFS Win 82  Linux swap / So c1  DRDOS/sec (FAT-
 2  XENIX root      39  Plan 9          83  Linux           c4  DRDOS/sec (FAT-
 3  XENIX usr       3c  PartitionMagic  84  OS/2 hidden C:  c6  DRDOS/sec (FAT-
 4  FAT16 <32M      40  Venix 80286     85  Linux extended  c7  Syrinx
 5  Extended        41  PPC PReP Boot   86  NTFS volume set da  Non-FS data
 6  FAT16           42  SFS             87  NTFS volume set db  CP/M / CTOS / .
 7  HPFS/NTFS/exFAT 4d  QNX4.x          88  Linux plaintext de  Dell Utility
 8  AIX             4e  QNX4.x 2nd part 8e  Linux LVM       df  BootIt
 9  AIX bootable    4f  QNX4.x 3rd part 93  Amoeba          e1  DOS access
 a  OS/2 Boot Manag 50  OnTrack DM      94  Amoeba BBT      e3  DOS R/O
 b  W95 FAT32       51  OnTrack DM6 Aux 9f  BSD/OS          e4  SpeedStor
 c  W95 FAT32 (LBA) 52  CP/M            a0  IBM Thinkpad hi eb  BeOS fs
 e  W95 FAT16 (LBA) 53  OnTrack DM6 Aux a5  FreeBSD         ee  GPT
 f  W95 Ext'd (LBA) 54  OnTrackDM6      a6  OpenBSD         ef  EFI (FAT-12/16/
10  OPUS            55  EZ-Drive        a7  NeXTSTEP        f0  Linux/PA-RISC b
11  Hidden FAT12    56  Golden Bow      a8  Darwin UFS      f1  SpeedStor
12  Compaq diagnost 5c  Priam Edisk     a9  NetBSD          f4  SpeedStor
14  Hidden FAT16 <3 61  SpeedStor       ab  Darwin boot     f2  DOS secondary
16  Hidden FAT16    63  GNU HURD or Sys af  HFS / HFS+      fb  VMware VMFS
17  Hidden HPFS/NTF 64  Novell Netware  b7  BSDI fs         fc  VMware VMKCORE
18  AST SmartSleep  65  Novell Netware  b8  BSDI swap       fd  Linux raid auto
1b  Hidden W95 FAT3 70  DiskSecure Mult bb  Boot Wizard hid fe  LANstep
1c  Hidden W95 FAT3 75  PC/IX           be  Solaris boot    ff  BBT
1e  Hidden W95 FAT1 80  Old Minix
Hex code (type L to list all codes): 8e
Changed type of partition 'Linux' to 'Linux LVM'

Command (m for help): p

Disk /dev/sda: 322.1 GB, 322122547200 bytes, 629145600 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 1048576 bytes
Disk label type: dos
Disk identifier: 0x000c57d5

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048     2099199     1048576   83  Linux
/dev/sda2         2099200   314572799   156236800   8e  Linux LVM
/dev/sda3       314572800   629145599   157286400   8e  Linux LVM

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

Calling ioctl() to re-read partition table.

WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table. The new table will be used at
the next reboot or after you run partprobe(8) or kpartx(8)
Syncing disks.
[root@devsim ~]#

[root@devsim ~]# pvdisplay
  --- Physical volume ---
  PV Name               /dev/sda2
  VG Name               rhel_devsimkapel
  PV Size               <149.00 GiB / not usable 2.00 MiB
  Allocatable           yes
  PE Size               4.00 MiB
  Total PE              38143
  Free PE               1
  Allocated PE          38142
  PV UUID               JnWKE8-ZFcN-7Jqb-ocM7-Y5Ki-cD3k-1CUEhe

[root@devsim ~]# fdisk -l

Disk /dev/sda: 322.1 GB, 322122547200 bytes, 629145600 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 1048576 bytes
Disk label type: dos
Disk identifier: 0x000c57d5

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048     2099199     1048576   83  Linux
/dev/sda2         2099200   314572799   156236800   8e  Linux LVM
/dev/sda3       314572800   629145599   157286400   8e  Linux LVM

Disk /dev/mapper/rhel_devsimkapel-root: 107.4 GB, 107374182400 bytes, 209715200 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 1048576 bytes


Disk /dev/mapper/rhel_devsimkapel-swap: 8455 MB, 8455716864 bytes, 16515072 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 1048576 bytes


Disk /dev/mapper/rhel_devsimkapel-home: 44.1 GB, 44149243904 bytes, 86228992 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 1048576 bytes

[root@devsim ~]# 

[root@devsim ~]# pvcreate /dev/sda3
  Physical volume "/dev/sda3" successfully created.
[root@devsim ~]#
[root@devsim ~]# pvdisplay
  --- Physical volume ---
  PV Name               /dev/sda2
  VG Name               rhel_devsimkapel
  PV Size               <149.00 GiB / not usable 2.00 MiB
  Allocatable           yes
  PE Size               4.00 MiB
  Total PE              38143
  Free PE               1
  Allocated PE          38142
  PV UUID               JnWKE8-ZFcN-7Jqb-ocM7-Y5Ki-cD3k-1CUEhe

  "/dev/sda3" is a new physical volume of "150.00 GiB"
  --- NEW Physical volume ---
  PV Name               /dev/sda3
  VG Name
  PV Size               150.00 GiB
  Allocatable           NO
  PE Size               0
  Total PE              0
  Free PE               0
  Allocated PE          0
  PV UUID               JqUaT7-OibZ-objt-14e1-CU8A-bY1V-Oe3wxh

[root@devsim ~]#

[root@devsim ~]# vgs
  VG               #PV #LV #SN Attr   VSize   VFree
  rhel_devsimkapel   2   3   0 wz--n- 298.99g 150.00g
[root@devsim ~]#
[root@devsim ~]# lvs
  LV   VG               Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  home rhel_devsimkapel -wi-ao---- <41.12g
  root rhel_devsimkapel -wi-ao---- 100.00g
  swap rhel_devsimkapel -wi-ao----  <7.88g
[root@devsim ~]#
[root@devsim ~]# lvextend -L +150G /dev/mapper/rhel_devsimkapel-root
  Size of logical volume rhel_devsimkapel/root changed from 100.00 GiB (25600 extents) to 250.00 GiB (64000 extents).
  Logical volume rhel_devsimkapel/root successfully resized.
[root@devsim ~]#

[root@devsim ~]# df -hT
Filesystem                        Type      Size  Used Avail Use% Mounted on
/dev/mapper/rhel_devsimkapel-root xfs       100G   87G   13G  88% /
devtmpfs                          devtmpfs  7.8G     0  7.8G   0% /dev
tmpfs                             tmpfs     7.8G     0  7.8G   0% /dev/shm
tmpfs                             tmpfs     7.8G  169M  7.6G   3% /run
tmpfs                             tmpfs     7.8G     0  7.8G   0% /sys/fs/cgroup
/dev/sda1                         xfs      1014M  143M  872M  15% /boot
/dev/mapper/rhel_devsimkapel-home xfs        42G   33M   42G   1% /home
tmpfs                             tmpfs     1.6G     0  1.6G   0% /run/user/0
[root@devsim ~]#

[root@devsim ~]# xfs_growfs /dev/mapper/rhel_devsimkapel-root
meta-data=/dev/mapper/rhel_devsimkapel-root isize=512    agcount=8, agsize=3276800 blks
         =                       sectsz=4096  attr=2, projid32bit=1
         =                       crc=1        finobt=0 spinodes=0
data     =                       bsize=4096   blocks=26214400, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
log      =internal               bsize=4096   blocks=6400, version=2
         =                       sectsz=4096  sunit=1 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
data blocks changed from 26214400 to 65536000
[root@devsim ~]#
[root@devsim ~]# df -h
Filesystem                         Size  Used Avail Use% Mounted on
/dev/mapper/rhel_devsimkapel-root  250G   87G  163G  35% /
devtmpfs                           7.8G     0  7.8G   0% /dev
tmpfs                              7.8G     0  7.8G   0% /dev/shm
tmpfs                              7.8G  169M  7.6G   3% /run
tmpfs                              7.8G     0  7.8G   0% /sys/fs/cgroup
/dev/sda1                         1014M  143M  872M  15% /boot
/dev/mapper/rhel_devsimkapel-home   42G   33M   42G   1% /home
tmpfs                              1.6G     0  1.6G   0% /run/user/0
[root@devsim ~]#

[root@devsim ~]# vgs
  VG               #PV #LV #SN Attr   VSize   VFree
  rhel_devsimkapel   2   3   0 wz--n- 298.99g    0
[root@devsim ~]# lvs
  LV   VG               Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  home rhel_devsimkapel -wi-ao---- <41.12g
  root rhel_devsimkapel -wi-ao---- 250.00g
  swap rhel_devsimkapel -wi-ao----  <7.88g
[root@devsim ~]# pvs
  PV         VG               Fmt  Attr PSize    PFree
  /dev/sda2  rhel_devsimkapel lvm2 a--  <149.00g    0
  /dev/sda3  rhel_devsimkapel lvm2 a--  <150.00g    0
[root@devsim ~]#