Btrfs bigboot

changelogs/fragments/btrfs_bigboot.yml

@@ -0,0 +1,5 @@
+major_changes:
+- add bigboot support for Btrfs next partition
+minor_changes:
+- show console log output from bigboot even if quiet kernel arg is set
+- do bigboot LVM changes with Ansible instead of pre-mount hook

roles/bigboot/README.md

@@ -6,8 +6,7 @@ The role is designed to support the automation of RHEL in-place upgrades, but ca
 
 ## Contents
 
-The role contains the shell scripts to increase the size of the boot partition, as well as the script wrapping it to run as part of the pre-mount step during the boot process.
-Finally, there is a copy of the [`sfdisk`](https://man7.org/linux/man-pages/man8/sfdisk.8.html) binary with version `2.38.1` to ensure the extend script will work regardless of the `util-linux` package installed in the target host.
+The role configures a dracut pre-mount hook that executes during a reboot to increase the size of the boot partition and filesystem. To make room for the boot size increase, the role first shrinks the size of the next partition after the boot partition. This next partition must contain either an LVM physical volume or a Btrfs filesystem volume. There must be sufficient free space in the LVM volume group or Btrfs filesystem to accommodate the reduced size.
 
 > **WARNING!**
 >
@@ -25,31 +24,62 @@ The variable `bigboot_partition_size` specifies the minimum required size of the
 
 This variable is deprecated and will be removed in a future release. Use `bigboot_partition_size` instead.
 
-The variable `bigboot_size` specifies by how much the size of the boot partition is to be increased. The value can be either in bytes or with optional single letter suffix (1024 bases) using [human_to_bytes](https://docs.ansible.com/ansible/latest/collections/ansible/builtin/human_to_bytes_filter.html) filter plugin. 
+The variable `bigboot_size` specifies by how much the size of the boot partition is to be increased. The value can be either in bytes or with optional single letter suffix (1024 bases) using [human_to_bytes](https://docs.ansible.com/ansible/latest/collections/ansible/builtin/human_to_bytes_filter.html) filter plugin.
 
 > **Note**
 >
-> The size increase may be slightly less than the specified value as the role will round down to the nearest multiple of the extent size of the LVM physical volume in the partition above the boot partition.
+> The size increase may be slightly less than the specified value as the role will round down to the nearest multiple of the LVM volume group extent size or Btrfs sector size used for the next partition after the boot partition.
 
-## Example of a playbook to run the role
-The following yaml is an example of a playbook that runs the role against a group of hosts named `rhel` and increasing the size of its boot partition by 1G.
-The boot partition is automatically retrieved by the role by identifying the existing mounted partition to `/boot` and passing the information to the script using the `kernel_opts`.
+## Example playbook
+The following yaml demonstrates an example playbook that runs the role to increase the size of the target hosts boot partition to 1.5G:
 
 ```yaml
 - name: Extend boot partition playbook
   hosts: all
   vars:
-    bigboot_partition_size: 1G
+    bigboot_partition_size: 1.5G
   roles:
     - bigboot
 ```
 
 # Validate execution
-The script will add an entry to the kernel messages (`/dev/kmsg`) with success or failure and the time it took to process.
-In case of failure, it may also include an error message retrieved from the execution of the script.
+The "Validate boot filesystem new size" task at the end of the run will indicate success or failure of the boot partition size increase. For example:
 
-A successful execution will look similar to this:
+```
+TASK [bigboot : Validate boot filesystem new size] ****************************************
+ok: [fedora] => {
+    "changed": false,
+    "msg": "Boot filesystem size is now 1.44 GB (503.46 MB increase)"
+```
+
+If the boot partition was already equal to or greater than the given size, the bigboot pre-mount hook configuration is skipped and the host will not reboot. In this case, the run will end with the "Validate increase requested" task indicating nothing happened. For example:
+
+```
+TASK [bigboot : Validate increase requested] **********************************************
+ok: [fedora] => {
+    "msg": "Nothing to do! Boot partition already equal to or greater than requested size."
+}
+```
+
+During the reboot, the bigboot pre-mount hook logs progress messages to the console. After the reboot, `journalctl` can be used to review the log output. For example, a successful run will look similar to this:
 ```bash
-[root@localhost ~]# dmesg |grep pre-mount
-[  357.163522] [dracut-pre-mount] Boot partition /dev/vda1 successfully increased by 1G (356 seconds)
+# journalctl --boot --unit=dracut-pre-mount
+Jul 02 09:40:12 fedora systemd[1]: Starting dracut-pre-mount.service - dracut pre-mount hook...
+Jul 02 09:40:12 fedora dracut-pre-mount[498]: bigboot: Shrinking partition vda3 by 536870912
+Jul 02 09:40:12 fedora dracut-pre-mount[498]: bigboot: Moving up partition vda3 by 536870912
+Jul 02 09:40:16 fedora dracut-pre-mount[508]: bigboot: Partition move is progressing, please wait! (00:00:01)
+Jul 02 09:40:48 fedora dracut-pre-mount[498]: bigboot: Increasing boot partition vda2 by 536870912
+Jul 02 09:40:49 fedora dracut-pre-mount[498]: bigboot: Updating kernel partition table
+Jul 02 09:40:50 fedora dracut-pre-mount[498]: bigboot: Growing the /boot ext4 filesystem
+Jul 02 09:40:50 fedora dracut-pre-mount[528]: e2fsck 1.47.0 (5-Feb-2023)
+Jul 02 09:40:50 fedora dracut-pre-mount[528]: Pass 1: Checking inodes, blocks, and sizes
+Jul 02 09:40:50 fedora dracut-pre-mount[528]: Pass 2: Checking directory structure
+Jul 02 09:40:50 fedora dracut-pre-mount[528]: Pass 3: Checking directory connectivity
+Jul 02 09:40:50 fedora dracut-pre-mount[528]: Pass 4: Checking reference counts
+Jul 02 09:40:50 fedora dracut-pre-mount[528]: Pass 5: Checking group summary information
+Jul 02 09:40:50 fedora dracut-pre-mount[528]: /dev/vda2: 38/65536 files (10.5% non-contiguous), 83665/262144 blocks
+Jul 02 09:40:50 fedora dracut-pre-mount[529]: resize2fs 1.47.0 (5-Feb-2023)
+Jul 02 09:40:50 fedora dracut-pre-mount[529]: Resizing the filesystem on /dev/vda2 to 393216 (4k) blocks.
+Jul 02 09:40:50 fedora dracut-pre-mount[529]: The filesystem on /dev/vda2 is now 393216 (4k) blocks long.
+Jul 02 09:40:50 fedora dracut-pre-mount[493]: Boot partition vda2 successfully increased by 536870912 (38 seconds)
 ```