Hi,

We run Openstack and need to provide instances that have very large root disks (> 2 TB) and it looks like cloud-init doesn't want to use the entire space.

The regular Ubuntu cloud image has MBR and it doesn't see more than 2 TB, but even the GPT version (http://cloud-images.ubuntu.com/xenial/current/xenial-server-cloudimg-amd64-uefi1.img) still fails to see more than 2 TB.

root@ubuntu-16:~# df -h
Filesystem      Size  Used Avail Use% Mounted on
udev            121G     0  121G   0% /dev
tmpfs            25G  8.6M   25G   1% /run
/dev/vda1       2.0T  857M  2.0T   1% /
tmpfs           121G     0  121G   0% /dev/shm
tmpfs           5.0M     0  5.0M   0% /run/lock
tmpfs           121G     0  121G   0% /sys/fs/cgroup
tmpfs            25G     0   25G   0% /run/user/1000

root@ubuntu-16:~# parted /dev/vda p
Model: Virtio Block Device (virtblk)
Disk /dev/vda: 5583GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:

Number  Start   End     Size    Type     File system  Flags
 1      1049kB  2199GB  2199GB  primary  ext4         boot

root@ubuntu-16:~# lsblk
NAME   MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
vda    253:0    0  5.1T  0 disk
└─vda1 253:1    0    2T  0 part /
root@ubuntu-16:~# dpkg -l | grep cloud-init
ii  cloud-init                       17.2-35-gf576b2a2-0ubuntu1~16.04.2         all          Init scripts for cloud instances
ii  cloud-initramfs-copymods         0.27ubuntu1.5                              all          copy initramfs modules into root filesystem for later use
ii  cloud-initramfs-dyn-netconf      0.27ubuntu1.5                              all          write a network interface file in /run for BOOTIF


The cloud-init.log looks like the disk growing and file system resizing went fine:

018-04-10 14:14:31,332 - stages.py[DEBUG]: Running module growpart (<module 'cloudinit.config.cc_growpart' from '/usr/lib/python3/dist-packages/cloudinit/config/cc_growpart.py'>) with frequency always
2018-04-10 14:14:31,332 - handlers.py[DEBUG]: start: init-network/config-growpart: running config-growpart with frequency always
2018-04-10 14:14:31,332 - helpers.py[DEBUG]: Running config-growpart using lock (<cloudinit.helpers.DummyLock object at 0x7f98107d9a90>)
2018-04-10 14:14:31,332 - cc_growpart.py[DEBUG]: No 'growpart' entry in cfg.  Using default: {'mode': 'auto', 'ignore_growroot_disabled': False, 'devices': ['/']}
2018-04-10 14:14:31,332 - util.py[DEBUG]: Running command ['growpart', '--help'] with allowed return codes [0] (shell=False, capture=True)
2018-04-10 14:14:31,352 - util.py[DEBUG]: Reading from /proc/1192/mountinfo (quiet=False)
2018-04-10 14:14:31,352 - util.py[DEBUG]: Read 2621 bytes from /proc/1192/mountinfo
2018-04-10 14:14:31,353 - util.py[DEBUG]: Running command ['systemd-detect-virt', '--quiet', '--container'] with allowed return codes [0] (shell=False, capture=True)
2018-04-10 14:14:31,355 - util.py[DEBUG]: Running command ['running-in-container'] with allowed return codes [0] (shell=False, capture=True)
2018-04-10 14:14:31,356 - util.py[DEBUG]: Running command ['lxc-is-container'] with allowed return codes [0] (shell=False, capture=True)
2018-04-10 14:14:31,357 - util.py[DEBUG]: Reading from /proc/1/environ (quiet=False)
2018-04-10 14:14:31,358 - util.py[DEBUG]: Read 153 bytes from /proc/1/environ
2018-04-10 14:14:31,358 - util.py[DEBUG]: Reading from /proc/self/status (quiet=False)
2018-04-10 14:14:31,358 - util.py[DEBUG]: Read 906 bytes from /proc/self/status
2018-04-10 14:14:31,358 - util.py[DEBUG]: Reading from /sys/class/block/vda1/partition (quiet=False)
2018-04-10 14:14:31,358 - util.py[DEBUG]: Read 2 bytes from /sys/class/block/vda1/partition
2018-04-10 14:14:31,358 - util.py[DEBUG]: Reading from /sys/devices/pci0000:00/0000:00:04.0/virtio1/block/vda/dev (quiet=False)
2018-04-10 14:14:31,359 - util.py[DEBUG]: Read 6 bytes from /sys/devices/pci0000:00/0000:00:04.0/virtio1/block/vda/dev
2018-04-10 14:14:31,359 - util.py[DEBUG]: Running command ['growpart', '--dry-run', '/dev/vda', '1'] with allowed return codes [0] (shell=False, capture=True)
2018-04-10 14:14:31,504 - util.py[DEBUG]: Running command ['growpart', '/dev/vda', '1'] with allowed return codes [0] (shell=False, capture=True)
2018-04-10 14:14:31,567 - util.py[DEBUG]: resize_devices took 0.215 seconds
2018-04-10 14:14:31,567 - cc_growpart.py[INFO]: '/' resized: changed (/dev/vda, 1) from 2359296000 to 2199022206464
2018-04-10 14:14:31,567 - handlers.py[DEBUG]: finish: init-network/config-growpart: SUCCESS: config-growpart ran successfully
2018-04-10 14:14:31,567 - stages.py[DEBUG]: Running module resizefs (<module 'cloudinit.config.cc_resizefs' from '/usr/lib/python3/dist-packages/cloudinit/config/cc_resizefs.py'>) with frequency always
2018-04-10 14:14:31,568 - handlers.py[DEBUG]: start: init-network/config-resizefs: running config-resizefs with frequency always
2018-04-10 14:14:31,568 - helpers.py[DEBUG]: Running config-resizefs using lock (<cloudinit.helpers.DummyLock object at 0x7f9810347390>)
2018-04-10 14:14:31,568 - schema.py[DEBUG]: Ignoring schema validation. python-jsonschema is not present
2018-04-10 14:14:31,568 - util.py[DEBUG]: Reading from /proc/1192/mountinfo (quiet=False)
2018-04-10 14:14:31,568 - util.py[DEBUG]: Read 2621 bytes from /proc/1192/mountinfo
2018-04-10 14:14:31,569 - cc_resizefs.py[DEBUG]: resize_info: dev=/dev/vda1 mnt_point=/ path=/
2018-04-10 14:14:31,569 - util.py[DEBUG]: Running command ['systemd-detect-virt', '--quiet', '--container'] with allowed return codes [0] (shell=False, capture=True)
2018-04-10 14:14:31,571 - util.py[DEBUG]: Running command ['running-in-container'] with allowed return codes [0] (shell=False, capture=True)
2018-04-10 14:14:31,572 - util.py[DEBUG]: Running command ['lxc-is-container'] with allowed return codes [0] (shell=False, capture=True)
2018-04-10 14:14:31,574 - util.py[DEBUG]: Reading from /proc/1/environ (quiet=False)
2018-04-10 14:14:31,574 - util.py[DEBUG]: Read 153 bytes from /proc/1/environ
2018-04-10 14:14:31,574 - util.py[DEBUG]: Reading from /proc/self/status (quiet=False)
2018-04-10 14:14:31,574 - util.py[DEBUG]: Read 906 bytes from /proc/self/status
2018-04-10 14:14:31,575 - cc_resizefs.py[DEBUG]: Resizing / (ext4) using resize2fs /dev/vda1
2018-04-10 14:14:31,575 - util.py[DEBUG]: Running command ('resize2fs', '/dev/vda1') with allowed return codes [0] (shell=False, capture=True)
2018-04-10 14:14:47,291 - util.py[DEBUG]: Resizing took 15.716 seconds
2018-04-10 14:14:47,291 - cc_resizefs.py[DEBUG]: Resized root filesystem (type=ext4, val=True)
2018-04-10 14:14:47,292 - handlers.py[DEBUG]: finish: init-network/config-resizefs: SUCCESS: config-resizefs ran successfully


On the other hand, the Ubuntu 14.04 image with GPT works fine though and resizes the root to use the entire disk space provided, despite some errors in the cloud-init.log file:

root@14-gpt:~# df -h
Filesystem      Size  Used Avail Use% Mounted on
udev            121G   12K  121G   1% /dev
tmpfs            25G  352K   25G   1% /run
/dev/vda1       5.0T  811M  4.8T   1% /
none            4.0K     0  4.0K   0% /sys/fs/cgroup
none            5.0M     0  5.0M   0% /run/lock
none            121G     0  121G   0% /run/shm
none            100M     0  100M   0% /run/user
/dev/vda15      105M  3.2M  102M   4% /boot/efi

root@14-gpt:~# parted /dev/vda p
Model: Virtio Block Device (virtblk)
Disk /dev/vda: 5583GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt

Number  Start   End     Size    File system  Name  Flags
14      1049kB  5243kB  4194kB                     bios_grub
15      5243kB  116MB   111MB   fat32              boot
 1      116MB   5583GB  5583GB  ext4

root@14-gpt:~# lsblk
NAME    MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
vda     253:0    0   5.1T  0 disk
├─vda1  253:1    0   5.1T  0 part /
├─vda14 253:14   0     4M  0 part
└─vda15 253:15   0   106M  0 part /boot/efi

root@14-gpt:~# dpkg -l | grep cloud-init
ii  cloud-init                       0.7.5-0ubuntu1.22                            all          Init scripts for cloud instances

Errors in the cloud-init.log file:

2018-04-10 14:42:40,537 - importer.py[DEBUG]: Looking for modules ['cc_growpart', 'cloudinit.config.cc_growpart'] that have attributes ['handle']
2018-04-10 14:42:40,538 - importer.py[DEBUG]: Failed at attempted import of 'cc_growpart' due to: No module named cc_growpart
2018-04-10 14:42:40,538 - importer.py[DEBUG]: Found cc_growpart with attributes ['handle'] in ['cloudinit.config.cc_growpart']
2018-04-10 14:42:40,538 - importer.py[DEBUG]: Looking for modules ['cc_resizefs', 'cloudinit.config.cc_resizefs'] that have attributes ['handle']
2018-04-10 14:42:40,538 - importer.py[DEBUG]: Failed at attempted import of 'cc_resizefs' due to: No module named cc_resizefs
2018-04-10 14:42:40,539 - importer.py[DEBUG]: Found cc_resizefs with attributes ['handle'] in ['cloudinit.config.cc_resizefs']
2018-04-10 14:42:40,539 - importer.py[DEBUG]: Looking for modules ['cc_set_hostname', 'cloudinit.config.cc_set_hostname'] that have attributes ['handle']
2018-04-10 14:42:40,539 - importer.py[DEBUG]: Failed at attempted import of 'cc_set_hostname' due to: No module named cc_set_hostname
2018-04-10 14:42:40,539 - importer.py[DEBUG]: Found cc_set_hostname with attributes ['handle'] in ['cloudinit.config.cc_set_hostname']
2018-04-10 14:42:40,539 - importer.py[DEBUG]: Looking for modules ['cc_update_hostname', 'cloudinit.config.cc_update_hostname'] that have attributes ['handle']
2018-04-10 14:42:40,540 - importer.py[DEBUG]: Failed at attempted import of 'cc_update_hostname' due to: No module named cc_update_hostname
2018-04-10 14:42:40,540 - importer.py[DEBUG]: Found cc_update_hostname with attributes ['handle'] in ['cloudinit.config.cc_update_hostname']
2018-04-10 14:42:40,540 - importer.py[DEBUG]: Looking for modules ['cc_update_etc_hosts', 'cloudinit.config.cc_update_etc_hosts'] that have attributes ['handle']
2018-04-10 14:42:40,540 - importer.py[DEBUG]: Failed at attempted import of 'cc_update_etc_hosts' due to: No module named cc_update_etc_hosts
2018-04-10 14:42:40,540 - importer.py[DEBUG]: Found cc_update_etc_hosts with attributes ['handle'] in ['cloudinit.config.cc_update_etc_hosts']
2018-04-10 14:42:40,540 - importer.py[DEBUG]: Looking for modules ['cc_ca_certs', 'cloudinit.config.cc_ca_certs'] that have attributes ['handle']
2018-04-10 14:42:40,541 - importer.py[DEBUG]: Failed at attempted import of 'cc_ca_certs' due to: No module named cc_ca_certs
2018-04-10 14:42:40,541 - importer.py[DEBUG]: Found cc_ca_certs with attributes ['handle'] in ['cloudinit.config.cc_ca_certs']
2018-04-10 14:42:40,541 - importer.py[DEBUG]: Looking for modules ['cc_rsyslog', 'cloudinit.config.cc_rsyslog'] that have attributes ['handle']
2018-04-10 14:42:40,541 - importer.py[DEBUG]: Failed at attempted import of 'cc_rsyslog' due to: No module named cc_rsyslog
2018-04-10 14:42:40,542 - importer.py[DEBUG]: Found cc_rsyslog with attributes ['handle'] in ['cloudinit.config.cc_rsyslog']
2018-04-10 14:42:40,542 - importer.py[DEBUG]: Looking for modules ['cc_users_groups', 'cloudinit.config.cc_users_groups'] that have attributes ['handle']
2018-04-10 14:42:40,542 - importer.py[DEBUG]: Failed at attempted import of 'cc_users_groups' due to: No module named cc_users_groups
2018-04-10 14:42:40,542 - importer.py[DEBUG]: Found cc_users_groups with attributes ['handle'] in ['cloudinit.config.cc_users_groups']
2018-04-10 14:42:40,542 - importer.py[DEBUG]: Looking for modules ['cc_ssh', 'cloudinit.config.cc_ssh'] that have attributes ['handle']
2018-04-10 14:42:40,542 - importer.py[DEBUG]: Failed at attempted import of 'cc_ssh' due to: No module named cc_ssh
2018-04-10 14:42:40,543 - importer.py[DEBUG]: Found cc_ssh with attributes ['handle'] in ['cloudinit.config.cc_ssh']
2018-04-10 14:42:40,543 - importer.py[DEBUG]: Looking for modules ['ubuntu', 'cloudinit.distros.ubuntu'] that have attributes ['Distro']
2018-04-10 14:42:40,543 - importer.py[DEBUG]: Failed at attempted import of 'ubuntu' due to: No module named ubuntu
2018-04-10 14:42:40,543 - importer.py[DEBUG]: Found ubuntu with attributes ['Distro'] in ['cloudinit.distros.ubuntu']
2018-04-10 14:42:40,543 - stages.py[DEBUG]: Using distro class <class 'cloudinit.distros.ubuntu.Distro'>
2018-04-10 14:42:40,544 - helpers.py[DEBUG]: Running config-migrator using lock (<cloudinit.helpers.DummyLock object at 0x7fc035363a90>)
2018-04-10 14:42:40,544 - cc_migrator.py[DEBUG]: Migrated 0 semaphore files to there canonicalized names
2018-04-10 14:42:40,544 - util.py[DEBUG]: Writing to /var/lib/cloud/instances/fb741604-966c-4142-8d81-904ab27ac5bd/sem/config_seed_random - wb: [420] 19 bytes
2018-04-10 14:42:40,544 - helpers.py[DEBUG]: Running config-seed_random using lock (<FileLock using file '/var/lib/cloud/instances/fb741604-966c-4142-8d81-904ab27ac5bd/sem/config_seed_random'>)
2018-04-10 14:42:40,544 - cc_seed_random.py[DEBUG]: seed_random: adding 512 bytes of random seed entropy to /dev/urandom
2018-04-10 14:42:40,544 - util.py[DEBUG]: Writing to /dev/urandom - ab: [None] 512 bytes
2018-04-10 14:42:40,545 - util.py[DEBUG]: Running command ['pollinate', '-q'] with allowed return codes [0] (shell=False, capture=False)
2018-04-10 14:42:41,192 - helpers.py[DEBUG]: Running config-bootcmd using lock (<cloudinit.helpers.DummyLock object at 0x7fc035302610>)
2018-04-10 14:42:41,192 - cc_bootcmd.py[DEBUG]: Skipping module named bootcmd, no 'bootcmd' key in configuration
2018-04-10 14:42:41,192 - util.py[DEBUG]: Writing to /var/lib/cloud/instances/fb741604-966c-4142-8d81-904ab27ac5bd/sem/config_write_files - wb: [420] 19 bytes
2018-04-10 14:42:41,192 - helpers.py[DEBUG]: Running config-write-files using lock (<FileLock using file '/var/lib/cloud/instances/fb741604-966c-4142-8d81-904ab27ac5bd/sem/config_write_files'>)
2018-04-10 14:42:41,192 - cc_write_files.py[DEBUG]: Skipping module named write-files, no/empty 'write_files' key in configuration
2018-04-10 14:42:41,193 - helpers.py[DEBUG]: Running config-growpart using lock (<cloudinit.helpers.DummyLock object at 0x7fc035302510>)
2018-04-10 14:42:41,193 - cc_growpart.py[DEBUG]: No 'growpart' entry in cfg.  Using default: {'ignore_growroot_disabled': False, 'mode': 'auto', 'devices': ['/']}
2018-04-10 14:42:41,193 - util.py[DEBUG]: Running command ['growpart', '--help'] with allowed return codes [0] (shell=False, capture=True)
2018-04-10 14:42:41,197 - util.py[DEBUG]: Reading from /proc/945/mountinfo (quiet=False)
2018-04-10 14:42:41,197 - util.py[DEBUG]: Read 1174 bytes from /proc/945/mountinfo
2018-04-10 14:42:41,197 - util.py[DEBUG]: Reading from /sys/class/block/vda1/partition (quiet=False)
2018-04-10 14:42:41,197 - util.py[DEBUG]: Read 2 bytes from /sys/class/block/vda1/partition
2018-04-10 14:42:41,197 - util.py[DEBUG]: Reading from /sys/devices/pci0000:00/0000:00:04.0/virtio1/block/vda/dev (quiet=False)
2018-04-10 14:42:41,197 - util.py[DEBUG]: Read 6 bytes from /sys/devices/pci0000:00/0000:00:04.0/virtio1/block/vda/dev
2018-04-10 14:42:41,197 - util.py[DEBUG]: Running command ['growpart', '--dry-run', '/dev/vda', '1'] with allowed return codes [0] (shell=False, capture=True)
2018-04-10 14:42:41,223 - util.py[DEBUG]: Running command ['growpart', '/dev/vda', '1'] with allowed return codes [0] (shell=False, capture=True)
2018-04-10 14:42:42,276 - util.py[DEBUG]: resize_devices took 1.080 seconds
2018-04-10 14:42:42,276 - cc_growpart.py[INFO]: '/' resized: changed (/dev/vda, 1) from 2144321024 to 5583341075968


I also attached the output generated from "cloud-init collect-logs" from a Ubuntu 16.04 (GPT) instance deployed with a disk of 5.1 TB

Thank you.