LTS

    Innovation Version

      FAQs

      openEuler Fails to Start After It Is Installed to the Second Disk

      Symptom

      The OS is installed on the second disk sdb during the installation, causing startup failure.

      Possible Causes

      When openEuler is installed to the second disk, MBR and GRUB are installed to the second disk sdb by default. The following two situations may occur:

      1. openEuler installed on the first disk is loaded and started if it is complete.
      2. openEuler installed on the first disk fails to be started from hard disks if it is incomplete.

      The preceding two situations occur because the first disk sda is booted by default to start openEuler in the BIOS window. If openEuler is not installed on the sda disk, system restart fails.

      Solutions

      This problem can be solved using either of the following two methods:

      • During the openEuler installation, select the first disk or both disks, and install the boot loader on the first disk sda.
      • After installing openEuler, restart it by modifying the boot option in the BIOS window.

      openEuler Enters Emergency Mode After It Is Started

      Symptom

      openEuler enters emergency mode after it is powered on.

      Possible Causes

      Damaged OS files result in disk mounting failure, or overpressured I/O results in disk mounting timeout (threshold: 90s).

      An unexpected system power-off and low I/O performance of disks may also cause the problem.

      Solutions

      1. Log in to openEuler as the root user.

      2. Check and restore files by using the file system check (fsck) tool, and restart openEuler.

        NOTE:
        The fsck tool checks and maintains inconsistent file systems. If the system is powered off or a disk is faulty, run the fsck command to check file systems. Run the fsck.ext3 -h and fsck.ext4 -h commands to view the usage method of the fsck tool.

      If you want to disable the timeout mechanism of disk mounting, add x-systemd.device-timeout=0 to the etc/fstab file. For example:

      #
      # /etc/fstab
      # Created by anaconda on Mon Sep 14 17:25:48 2015
      #
      # Accessible filesystems, by reference, are maintained under '/dev/disk'
      # See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
      #
      /dev/mapper/openEuler-root / ext4 defaults,x-systemd.device-timeout=0 0 0
      UUID=afcc811f-4b20-42fc-9d31-7307a8cfe0df /boot ext4 defaults,x-systemd.device-timeout=0 0 0
      /dev/mapper/openEuler-home /home ext4 defaults 0 0
      /dev/mapper/openEuler-swap swap swap defaults 0 0
      

      openEuler Fails to Be Reinstalled When an Unactivated Logical Volume Group Exists

      Symptom

      After a disk fails, openEuler fails to be reinstalled because a logical volume group that cannot be activated exists in openEuler.

      Possible Causes

      During the installation of openEuler, a logical volume group cannot be activated.

      Solutions

      Before reinstalling openEuler, restore the abnormal logical volume group to the normal status or clear it. For example:

      • Restore the logical volume group.

        1. Run the following command to clear the active status of the abnormal logical volume group to ensure that the error message "Can't open /dev/sdc exclusively mounted filesystem" is not displayed:

           vgchange -a n testvg32947
          
        2. Run the following command to recreate a physical volume based on the backup file:

          pvcreate --uuid JT7zlL-K5G4-izjB-3i5L-e94f-7yuX-rhkLjL --restorefile /etc/lvm/backup/testvg32947 /dev/sdc
          
        3. Run the following command to restore the logical volume group information:

          vgcfgrestore testvg32947
          
        4. Run the following command to reactivate the logical volume group:

           vgchange -ay testvg32947
          
      • Run the following commands to clear the logical volume group:

        vgchange -a n testvg32947
        vgremove -y testvg32947
        

      An Exception Occurs During the Selection of the Installation Source

      Symptom

      After the installation source is selected, the message "Error checking software selection" is displayed.

      Possible Causes

      This is because the software package dependency in the installation source is abnormal.

      Solutions

      Check whether the installation source is abnormal. Use the new installation source.

      Kdump Service Fails to Be Enabled

      Symptom

      Run the systemctl status kdump command. The following information is displayed, indicating that no memory is reserved.

      Possible Causes

      The kdump service requires the system to reserve memory for running the kdump kernel. However, the system does not reserve memory for the kdump service. As a result, the kdump service cannot be started.

      Solutions

      For the scenario where the OS has been installed

      1. Add crashkernel=1024M,high to /boot/efi/EFI/openEuler/grub.cfg.

      2. Restart the system for configuration to take effect.

      3. Run the following command to check the kdump status:

        systemctl status kdump
        

        If the following information is displayed, the kdump status is active, indicating that the kdump service is enabled. No further action is required.

      Parameter Description

      The following table describes the parameters of the memory reserved for the kdump kernel.

      Table 1 crashkernel parameters

      Kernel Boot Parameter

      Description

      Default Value

      Remarks

      crashkernel=X

      Reserve X of the physical memory for kdump when the physical memory is less than 4 GB.

      None. You can adjust the value as required.

      This configuration method is used only when the memory is less than 4 GB. Ensure that the continuous available memory is sufficient.

      crashkernel=X@Y

      Reserve X of the memory at the start address Y for kdump.

      None. You can adjust the value as required.

      Ensure that the X of the memory at the start address Y is not reserved for other modules.

      crashkernel=X,high

      Reserve 256 MB of the physical memory for kdump when the physical memory is less than 4 GB, and X of the physical memory for kdump when the physical memory is greater than or equal to 4 GB.

      None. You can adjust the value based as required. The recommended value is 1024M,high.

      Ensure that 256 MB of the memory is reserved for continuous use when the physical memory is less than 4 GB and X of the memory is reserved when the physical memory is greater than or equal to 4 GB. The actual reserved memory size equals 256 MB plus X.

      crashkernel=X,low

      crashkernel=Y,high

      Reserve X of the physical memory for kdump when the physical memory is less than 4 GB and Y of the physical memory for kdump when the physical memory is greater than or equal to 4 GB.

      None. You can adjust the value as required.

      Ensure that X of the memory is reserved for continuous use when the physical memory is less than 4 GB and Y of the memory is reserved when the physical memory is greater than or equal to 4 GB. The actual reserved memory size equals X plus Y.

      Fails to Select Only One Disk for Reinstallation When openEuler Is Installed on a Logical Volume Consisting of Multiple Disks

      Symptom

      If openEuler is installed on a logical volume consisting of multiple disks, an error message will be displayed as shown in Figure 1 when you attempt to select one of the disks for reinstallation.

      Figure 1 Error message

      Possible Causes

      The previous logical volume contains multiple disks. If you select one of the disks for reinstallation, the logical volume will be damaged.

      Solutions

      The logical volume formed by multiple disks is equivalent to a volume group. Therefore, you only need to delete the corresponding volume group.

      1. Press Ctrl+Alt+F2 to switch to the CLI and run the following command to find the volume group:

        vgs
        

      2. Run the following command to delete the volume group:

        vgremove euleros
        
      3. Run the following command to restart the installation program for the modification to take effect:

        systemctl restart anaconda
        

        NOTE:
        You can also press Ctrl+Alt+F6 to return to the GUI and click Refresh in the lower right corner to refresh the storage configuration.

      openEuler Fails to Be Installed on an x86 PM in UEFI Mode due to Secure Boot Option Setting

      Symptom

      During the installation of openEuler on an x86 PM in UEFI mode, the system stays at the "No bootable device" page and the installation cannot continue because secure boot is set to enabled (by default, it is set to disabled), as shown in Figure 2.

      Figure 2 Dialog box showing "No bootable device"

      Possible Causes

      After secure boot is set to enabled, the mainboard verifies the boot program and OS. If the boot program and OS are not signed using the corresponding private key, they cannot pass the authentication of the built-in public key on the mainboard.

      Solutions

      Access the BIOS, set secure boot to disabled, and reinstall the openEuler.

      1. During the system startup, press F11 and enter the password Admin@9000 to access the BIOS.

      2. Choose Administer Secure Boot.

      3. Set Enforce Secure Boot to Disabled.

        NOTE:
        After Enforce Secure Boot is set to Disabled, save the settings and exit. Then, reinstall the system.

      pmie_check Is Reported in the messages Log During openEuler Installation

      Symptom

      During the OS installation, if you click Server > Performance tool, PCP is installed. After the OS is installed and restarted, an error "pmie_check failed in /usr/share/pcp/lib/pmie" is displayed in the /var/log/messages log.

      Possible Causes

      anaconda does not support the installation of SELinux policy module in the chroot environment. During the pcp-selinux installation, the postin script fails to execute the PCP-related SELinux policy module. As a result, an error is reported after the OS is restarted.

      Solutions

      After the OS is installed and restarted, perform either of the following two operations:

      1. Install SElinux policy module pcpupstream.

        /usr/libexec/pcp/bin/selinux-setup /var/lib/pcp/selinux install "pcpupstream"
        
      2. Reinstall pcp-selinux

        sudo dnf reinstall pcp-selinux
        

      Installation Fails when a User Selects Two Disks with OS Installed and Customizes Partitioning

      Symptom

      During the OS installation, the OS has been installed on two disks. In this case, if you select one disk for custom partitioning, and click Cancel to perform custom partitioning on the other disk, the installation fails.

      Possible Causes

      A user selects a disk for partitioning twice. After the user clicks Cancel and then selects the other disk, the disk information is incorrect. As a result, the installation fails.

      Solutions

      Select the target disk for custom partitioning. Do not frequently cancel the operation. If you have to cancel and select another disk, you are advised to reinstall the OS.

      Learn More About the Issue at:

      https://gitee.com/src-openeuler/anaconda/issues/I29P84?from=project-issue

      vmcore Fails to Be Generated by Kdump on the PM with LSI MegaRAID Card Installed

      Symptom

      After the Kdump service is deployed, kernel breaks down due to the manual execution of the echo c > /proc/sysrq-trigger command or kernel fault. When Kdump enables second kernel, an error "BRCM Debug mfi stat 0x2d, data len requested/completed 0x200/0x0" is reported in the MegaRAID driver, as shown in the following figure. As a result, vmcore fails to be generated.

      Error information

      Possible Causes

      The reset_devices parameter is configured by default and is enabled during second kernel startup, making MegaRAID driver or disk faulty. An error is reported when the vmcore file is dumped ana accesses the MegaRAID card. As a result, vmcore fails to be generated.

      Solutions

      Delete the reset_devices parameter in the /etc/sysconfig/kdump file on a PM, as shown in the following figure. Therefore, the I/O request will be responded when the MegaRAID driver resets the device during the second kernel startup, and vmcore will be successfully generated.

      Deleting reset_devices

      Bug Catching

      Buggy Content

      Bug Description

      Submit As Issue

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      PR

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      I can fix it online!

      Bug Type
      Specifications and Common Mistakes

      ● Misspellings or punctuation mistakes;

      ● Incorrect links, empty cells, or wrong formats;

      ● Chinese characters in English context;

      ● Minor inconsistencies between the UI and descriptions;

      ● Low writing fluency that does not affect understanding;

      ● Incorrect version numbers, including software package names and version numbers on the UI.

      Usability

      ● Incorrect or missing key steps;

      ● Missing prerequisites or precautions;

      ● Ambiguous figures, tables, or texts;

      ● Unclear logic, such as missing classifications, items, and steps.

      Correctness

      ● Technical principles, function descriptions, or specifications inconsistent with those of the software;

      ● Incorrect schematic or architecture diagrams;

      ● Incorrect commands or command parameters;

      ● Incorrect code;

      ● Commands inconsistent with the functions;

      ● Wrong screenshots.

      Risk Warnings

      ● Lack of risk warnings for operations that may damage the system or important data.

      Content Compliance

      ● Contents that may violate applicable laws and regulations or geo-cultural context-sensitive words and expressions;

      ● Copyright infringement.

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