I have assigned 800 gb on all my instance when create. however, I only can see root / have 10gb, but df -h never see it.

[#1]

Please refer to my attached snapshot for df -h. there is nothing 800gb. do I need to mkfs /dev/xvdb and mkdir /mydir and mount /dev/xvdb to /mydir and may have to change fstab at end.

any easy way to deal with ambari-server disk issues?

Please help. thanks,

[#2 · Accepted solution]

I guess you are using some type of cloud instance? Normally the images used for provision of these instances are based on small partitions for root even if you specifically requested a 800G disk.

Fortunately these are using LVM disk partitions.

The command lsblk will show you what "physical" disks you have:

 lsblk
NAME            MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
sda               8:0    0 931.5G  0 disk
├─sda1            8:1    0     4G  0 part
│ └─md1           9:1    0     4G  0 raid1 /
├─sda2            8:2    0     2G  0 part  [SWAP]
└─sda3            8:3    0 925.5G  0 part
  └─md3           9:3    0 925.5G  0 raid1
    ├─vg00-usr  252:0    0     5G  0 lvm   /usr
    ├─vg00-var  252:1    0   105G  0 lvm   /var
    └─vg00-home 252:2    0   165G  0 lvm   /home
sdb               8:16   0 931.5G  0 disk
├─sdb1            8:17   0     4G  0 part
│ └─md1           9:1    0     4G  0 raid1 /
├─sdb2            8:18   0     2G  0 part  [SWAP]
└─sdb3            8:19   0 925.5G  0 part
  └─md3           9:3    0 925.5G  0 raid1
    ├─vg00-usr  252:0    0     5G  0 lvm   /usr
    ├─vg00-var  252:1    0   105G  0 lvm   /var
    └─vg00-home 252:2    0   165G  0 lvm   /home

lvscan will show logical volumes and the sizes they are.

# lvscan 
ACTIVE '/dev/vg00/usr' [5.00 GiB] inherit 
ACTIVE '/dev/vg00/var' [105.00 GiB] inherit 
ACTIVE '/dev/vg00/home' [165.00 GiB] inherit

In HDP the two directories you should assign space to are /usr and /var and if they are already defined as an LVM partition you can resize with the resize2fs command.

sudo resize2fs /dev/vg00/usr

[#3]

thank you so much. even I need more time to digest it, I can tell this is what I need to know. thank you for spending time to help.

Robin