2024-04-29 (updated 2025-11-17) - LVM volumes (including /u01) may fail to mount after reboot on Oracle Linux 8 on AWS – FlashGrid Help Center

Summary

On Oracle Linux 8 on AWS, the /u01 volume (or any other LVM volume) may fail to mount after reboot preventing Oracle services from starting.

Symptoms

When the EC2 instance boots up, the LVM volumes are not mounted (no /u01 in the df command output):

$ df -h
Filesystem      Size  Used Avail Use% Mounted on
devtmpfs         16G     0   16G   0% /dev
tmpfs            16G     0   16G   0% /dev/shm
tmpfs            16G   25M   16G   1% /run
tmpfs            16G     0   16G   0% /sys/fs/cgroup
/dev/nvme0n1p1   35G  8.0G   28G  23% /
tmpfs           3.1G     0  3.1G   0% /run/user/1001
tmpfs           3.1G     0  3.1G   0% /run/user/1002
tmpfs           3.1G     0  3.1G   0% /run/user/0

The following messages are logged in /var/log/messages:

systemd[1]: dev-testvg-u01.device: Job dev-testvg-u01.device/start timed out.
systemd[1]: Timed out waiting for device dev-testvg-u01.device.
systemd[1]: Dependency failed for /u01.
systemd[1]: Dependency failed for Remote File Systems.
systemd[1]: remote-fs.target: Job remote-fs.target/start failed with result 'dependency'.
systemd[1]: u01.mount: Job u01.mount/start failed with result 'dependency'.
systemd[1]: dev-testvg-u01.device: Job dev-testvg-u01.device/start failed with result 'timeout'.

Affected Products

FlashGrid Cluster on AWS running Oracle Linux 8

FlashGrid Server on AWS running Oracle Linux 8

Affected Versions

The following systemd versions are affected:

from systemd-239-78.0.3 up to (not including) systemd-239-82.0.6

To determine the installed systemd version, please run:

$ rpm -q systemd

Root Cause

It is a bug in the Oracle Linux version of systemd RPM.

The Oracle Linux version of systemd includes the systemd-fstab-generator-reload-targets.service that is not present in RHEL 8. Disabling it prevents the issue.

Workaround

To prevent the issue:

A. Either mask systemd-fstab-generator-reload-targets.service manually, or update to FlashGrid software version 24.05 or later:

# systemctl mask systemd-fstab-generator-reload-targets.service

B. Add x-systemd.before=local-fs.target option to the /u01 filesystem in /etc/fstab (or the filesystem that is used for the Oracle Grid Infrastructure home if it is not /u01).

For example, change /dev/fgvg/u01 /u01 xfs defaults 0 0

to /dev/fgvg/u01 /u01 xfs defaults,x-systemd.before=local-fs.target 0 0

In case the system still experiences the issue after implementing A and B, switch to R6i or newer EC2 instance type.

To resolve the issue after it has already happened:

Run vgchange -a y as root to activate the LVM volumes.

Resolution

Apply systemd version systemd-239-82.0.6 or newer.