Migrating Oracle Linux 6 (OL6) to Oracle Linux 7 (OL7) Post ./bdareimagenode.sh Reboot Step Boots into the Dracut Emergency Shell (Doc ID 2794999.1)

Last updated on JULY 20, 2024

Applies to:

Big Data Appliance Integrated Software - Version 4.13.0 and later
x86_64

Symptoms

NOTE: In the examples that follow, user details, cluster names, hostnames, directory paths, filenames, etc. represent a fictitious sample (and are used to provide an illustrative example only). Any similarity to actual persons, or entities, living or dead, is purely coincidental and not intended in any manner.

Introduction

The five notes below apply to BDA 4.13 and higher when an OL6 to OL7 migration boots into the Dracut Emergency Shell.

Start with the first note i.e. this one and then navigate to the second and third. The last two notes are used when confirming the state of the OL6 OS in (Doc ID 2761414.1).

1. Migrating Oracle Linux 6 (OL6) to Oracle Linux 7 (OL7) Post ./bdareimagenode.sh Reboot Step Boots into the Dracut Emergency Shell (Doc ID 2794999.1).
2. How to Boot into the OL6 OS When BDA OL6 to OL7 Migration Reboot Step Remains Stuck in the Dracut Emergency Shell (Doc ID 2792691.1).
3. Confirming the State of the OL6 OS After Rebooting into that OS Post the BDA OL6 to OL7 Migration Reboot Step Being Stuck in the Dracut Emergency Shell (Doc ID 2761414.1).
4. How to Resolve a Missing DO_NOT_WIPE Label After Rebooting into the OL6 OS Post the BDA OL6 to OL7 Migration Reboot Step Being Stuck in the Dracut Emergency Shell (Doc ID 2761416.1).
5. How to Correct syslinux.cfg After Rebooting into the OL6 OS Post the BDA OL6 to OL7 Migration Reboot Step Being Stuck in the Dracut Emergency Shell (Doc ID 2675334.1).

Background

Migrating Oracle Linux 6 (OL6) to Oracle Linux 7 (OL6) using the documentation "10.8.3 Oracle Linux 6 to Oracle Linux 7 Migration Steps", fails to reboot the server.

At this point ./bdareimagenode.sh and subsequent steps up to the reboot step have been completed but the reboot step remains stuck in the Dracut Emergency Shell.

There are two cases that can land the post ./bdareimagenode.sh reboot, where the OS reimage is occurring, in the Dracut Emergency Shell, when migrating Oracle Linux 6 (OL6) to Oracle Linux 7 (OL7).

The cause and workaround for each Case differ. But the initial symptom is the same. Case 1 is the more likely to be encountered. The two Cases are discussed below.

Case 1

In this Case, the reboot does not boot into the installer due to a reboot misstep. The reboot steps remains stuck in the Dracut Emergency Shell. The consequence is that the OL7 OS is not installed. In this case it is possible to boot into the OL6 kernel and investigate the grub, syslinux.cfg, partitions, etc for errors, correct them and resume reboot into OL7.

Case 2

In this Case, the OL7 installation process gets manually interrupted preventing OL7 from being installed. The reboot steps remains stuck in the Dracut Emergency Shell. This can happen if there is a manual interruption during the post ./bdareimagenode.sh reboot, when the OS reimage is occurring. The consequence is that it is not possible to boot directly into the OL6 kernel because it has been wiped.

Initial symptom for Case 1 and Case 2

The reboot step remains stuck in the Dracut Emergency Shell. The stack is like that below.

dracut-initqueue[<X>]: Warning: dracut-initqueue timeout - starting timeout scripts
dracut-initqueue[<X>]: Warning: Could not boot.
dracut-initqueue[<X>]: Warning: /dev/root does not exist
Starting Dracut Emergency Shell
Warning: /dev/root does not exist

Generating "/run/initramfs/rdsosreport.txt"

Entering emergency mode. Exit the shell to continue.
Type "journalctl" to view the system logs.
You might want to save "/run/initramfs/rdsosreport.txt" to a USB stick or /boot
after mounting them and attach it to a bug report.

2. After entering into the Dracut Emergency Shell at the shell prompt:

Distinguishing between Case 1 and Case 2

In both cases above, the first step to resolve the issue is to try to boot into the OL6 OS using How to Boot into the OL6 OS When BDA OL6 to OL7 Migration Reboot Step Remains Stuck in the Dracut Emergency Shell (Doc ID 2792691.1). The differentiating factor between the cases is that in Case 1 it will be possible to boot into OL6. If it is not possible to boot into OL6 then the server is encountering Case 2.