6.2. Restoring the Self-Hosted Engine Environment

This section explains how to restore a self-hosted engine environment from a backup on a newly installed host. The supported restore method uses the engine-backup tool.

Warning

The restoration procedure requires the tar backup file produced by the engine-backup tool. If a third-party tool is used, it must create a backup of the tar file.
Restoring a self-hosted engine environment involves the following key actions:
  1. Create a newly installed Red Hat Enterprise Linux host and run the hosted-engine deployment script.
  2. Restore the Red Hat Virtualization Manager configuration settings and database content in the new Manager virtual machine.
  3. Remove self-hosted engine nodes in a Non Operational state and re-install them into the restored self-hosted engine environment.

Prerequisites

  • To restore a self-hosted engine environment, you must prepare a newly installed Red Hat Enterprise Linux system on a physical host.
  • The operating system version of the new host and Manager must be the same as that of the original host and Manager.
  • You must have Red Hat Subscription Manager entitlements for your new environment. For a list of the required repositories, see Subscribing to the Required Entitlements in the Installation Guide.
  • The fully qualified domain name of the new Manager must be the same fully qualified domain name as that of the original Manager. Forward and reverse lookup records must both be set in DNS.
  • You must prepare storage for the new self-hosted engine environment to use as the Manager virtual machine's shared storage domain. This domain must be at least 68 GB. For more information on preparing storage for your deployment, see the Storage chapter of the Administration Guide.

6.2.1. Creating a New Self-Hosted Engine Environment to be Used as the Restored Environment

You can restore a self-hosted engine on hardware that was used in the backed-up environment. However, you must use the failover host for the restored deployment. The failover host, Host 1, used in Section 6.1, “Backing up the Self-Hosted Engine Manager Virtual Machine” uses the default hostname of hosted_engine_1 which is also used in this procedure. Due to the nature of the restore process for the self-hosted engine, before the final synchronization of the restored engine can take place, this failover host will need to be removed, and this can only be achieved if the host had no virtual load when the backup was taken. You can also restore the backup on a separate hardware which was not used in the backed up environment and this is not a concern.

Important

This procedure assumes that you have a freshly installed Red Hat Enterprise Linux system on a physical host, have subscribed the host to the required entitlements, and installed the ovirt-hosted-engine-setup package. See Subscribing to the Required Entitlements in the Installation Guide and Section 2.1.1, “Installing the Self-Hosted Engine Packages” for more information.

Procedure 6.4. Creating a New Self-Hosted Environment to be Used as the Restored Environment

  1. Updating DNS

    Update your DNS so that the fully qualified domain name of the Red Hat Virtualization environment correlates to the IP address of the new Manager. In this procedure, fully qualified domain name was set as Manager.example.com. The fully qualified domain name provided for the engine must be identical to that given in the engine setup of the original engine that was backed up.
  2. Initiating Hosted Engine Deployment

    On the newly installed Red Hat Enterprise Linux host, run the hosted-engine deployment script. To escape the script at any time, use the CTRL+D keyboard combination to abort deployment. If running the hosted-engine deployment script over a network, it is recommended to use the screen window manager to avoid losing the session in case of network or terminal disruption. Install the screen package first if not installed.
    # screen
    # hosted-engine --deploy
  3. Preparing for Initialization

    The script begins by requesting confirmation to use the host as a hypervisor for use in a self-hosted engine environment.
    Continuing will configure this host for serving as hypervisor and create a VM where you have to install oVirt Engine afterwards. 
    Are you sure you want to continue? (Yes, No)[Yes]:
  4. Configuring Storage

    Select the type of storage to use.
    During customization use CTRL-D to abort.
    Please specify the storage you would like to use (glusterfs, iscsi, fc, nfs3, nfs4)[nfs3]:
    • For NFS storage types, specify the full address, using either the FQDN or IP address, and path name of the shared storage domain.
      Please specify the full shared storage connection path to use (example: host:/path): storage.example.com:/hosted_engine/nfs
    • For iSCSI, specify the iSCSI portal IP address, port, user name and password, and select a target name from the auto-detected list. You can only select one iSCSI target during the deployment.
      Please specify the iSCSI portal IP address:           
      Please specify the iSCSI portal port [3260]:           
      Please specify the iSCSI portal user:           
      Please specify the iSCSI portal password:
      Please specify the target name (auto-detected values) [default]:
    • For Gluster storage, specify the full address, using either the FQDN or IP address, and path name of the shared storage domain.

      Important

      Only replica 3 Gluster storage is supported. Ensure the following configuration has been made:
      • In the /etc/glusterfs/glusterd.vol file on all three Gluster servers, set rpc-auth-allow-insecure to on.
        option rpc-auth-allow-insecure on
      • Configure the volume as follows:
        gluster volume set volume cluster.quorum-type auto
        gluster volume set volume network.ping-timeout 10
        gluster volume set volume auth.allow \*
        gluster volume set volume group virt
        gluster volume set volume storage.owner-uid 36
        gluster volume set volume storage.owner-gid 36
        gluster volume set volume server.allow-insecure on
      Please specify the full shared storage connection path to use (example: host:/path): storage.example.com:/hosted_engine/gluster_volume
    • For Fibre Channel, the host bus adapters must be configured and connected, and the hosted-engine script will auto-detect the LUNs available. The LUNs must not contain any existing data.
      The following luns have been found on the requested target:
      [1]     3514f0c5447600351       30GiB   XtremIO XtremApp
                              status: used, paths: 2 active
                
      [2]     3514f0c5447600352       30GiB   XtremIO XtremApp
                              status: used, paths: 2 active
      
      Please select the destination LUN (1, 2) [1]:
  5. Configuring the Network

    The script detects possible network interface controllers (NICs) to use as a management bridge for the environment. It then checks your firewall configuration and offers to modify it for console (SPICE or VNC) access the Manager virtual machine. Provide a pingable gateway IP address, to be used by the ovirt-ha-agent, to help determine a host's suitability for running a Manager virtual machine.
    Please indicate a nic to set ovirtmgmt bridge on: (eth1, eth0) [eth1]:
    iptables was detected on your computer, do you wish setup to configure it? (Yes, No)[Yes]: 
    Please indicate a pingable gateway IP address [X.X.X.X]:
    
  6. Configuring the New Manager Virtual Machine

    The script creates a virtual machine to be configured as the new Manager virtual machine. Specify the boot device and, if applicable, the path name of the installation media, the image alias, the CPU type, the number of virtual CPUs, and the disk size. Specify a MAC address for the Manager virtual machine, or accept a randomly generated one. The MAC address can be used to update your DHCP server prior to installing the operating system on the Manager virtual machine. Specify memory size and console connection type for the creation of Manager virtual machine.
    Please specify the device to boot the VM from (cdrom, disk, pxe) [cdrom]: 
    Please specify an alias for the Hosted Engine image [hosted_engine]:  
    The following CPU types are supported by this host:
              - model_Penryn: Intel Penryn Family
              - model_Conroe: Intel Conroe Family
    Please specify the CPU type to be used by the VM [model_Penryn]: 
    Please specify the number of virtual CPUs for the VM [Defaults to minimum requirement: 2]: 
    Please specify the disk size of the VM in GB [Defaults to minimum requirement: 25]: 
    You may specify a MAC address for the VM or accept a randomly generated default [00:16:3e:77:b2:a4]: 
    Please specify the memory size of the VM in MB [Defaults to minimum requirement: 4096]: 
    Please specify the console type you want to use to connect to the VM (vnc, spice) [vnc]:
    
  7. Identifying the Name of the Host

    Specify the password for the admin@internal user to access the Administration Portal.
    A unique name must be provided for the name of the host, to ensure that it does not conflict with other resources that will be present when the engine has been restored from the backup. The name hosted_engine_1 can be used in this procedure because this host was placed into maintenance mode before the environment was backed up, enabling removal of this host between the restoring of the engine and the final synchronization of the host and the engine.
    Enter engine admin password: 
    Confirm engine admin password:
    Enter the name which will be used to identify this host inside the Administration Portal [hosted_engine_1]:
  8. Configuring the Hosted Engine

    Provide the fully qualified domain name for the new Manager virtual machine. This procedure uses the fully qualified domain name Manager.example.com. Provide the name and TCP port number of the SMTP server, the email address used to send email notifications, and a comma-separated list of email addresses to receive these notifications.

    Important

    The fully qualified domain name provided for the engine (Manager.example.com) must be the same fully qualified domain name provided when original Manager was initially set up.
    Please provide the FQDN for the engine you would like to use.
    This needs to match the FQDN that you will use for the engine installation within the VM.
     Note: This will be the FQDN of the VM you are now going to create,
     it should not point to the base host or to any other existing machine.
     Engine FQDN: Manager.example.com
    Please provide the name of the SMTP server through which we will send notifications [localhost]: 
    Please provide the TCP port number of the SMTP server [25]: 
    Please provide the email address from which notifications will be sent [root@localhost]: 
    Please provide a comma-separated list of email addresses which will get notifications [root@localhost]:
  9. Configuration Preview

    Before proceeding, the hosted-engine deployment script displays the configuration values you have entered, and prompts for confirmation to proceed with these values.
    Bridge interface                   : eth1
    Engine FQDN                        : Manager.example.com
    Bridge name                        : ovirtmgmt
    SSH daemon port                    : 22
    Firewall manager                   : iptables
    Gateway address                    : X.X.X.X
    Host name for web application      : hosted_engine_1
    Host ID                            : 1
    Image alias                        : hosted_engine
    Image size GB                      : 25
    Storage connection                 : storage.example.com:/hosted_engine/nfs
    Console type                       : vnc
    Memory size MB                     : 4096
    MAC address                        : 00:16:3e:77:b2:a4
    Boot type                          : pxe
    Number of CPUs                     : 2
    CPU Type                           : model_Penryn
    
    Please confirm installation settings (Yes, No)[Yes]:
    
  10. Creating the New Manager Virtual Machine

    The script creates the virtual machine to be configured as the Manager virtual machine and provides connection details. You must install an operating system on it before the hosted-engine deployment script can proceed on Hosted Engine configuration.
    [ INFO  ] Stage: Transaction setup
    [ INFO  ] Stage: Misc configuration
    [ INFO  ] Stage: Package installation
    [ INFO  ] Stage: Misc configuration
    [ INFO  ] Configuring libvirt
    [ INFO  ] Configuring VDSM
    [ INFO  ] Starting vdsmd
    [ INFO  ] Waiting for VDSM hardware info
    [ INFO  ] Waiting for VDSM hardware info
    [ INFO  ] Configuring the management bridge
    [ INFO  ] Creating Storage Domain
    [ INFO  ] Creating Storage Pool
    [ INFO  ] Connecting Storage Pool
    [ INFO  ] Verifying sanlock lockspace initialization
    [ INFO  ] Creating VM Image
    [ INFO  ] Disconnecting Storage Pool
    [ INFO  ] Start monitoring domain
    [ INFO  ] Configuring VM
    [ INFO  ] Updating hosted-engine configuration
    [ INFO  ] Stage: Transaction commit
    [ INFO  ] Stage: Closing up
    [ INFO  ] Creating VM
    You can now connect to the VM with the following command:
          /usr/bin/remote-viewer vnc://localhost:5900
    Use temporary password "3477XXAM" to connect to vnc console.
    Please note that in order to use remote-viewer you need to be able to run graphical applications.
    This means that if you are using ssh you have to supply the -Y flag (enables trusted X11 forwarding).
    Otherwise you can run the command from a terminal in your preferred desktop environment.
    If you cannot run graphical applications you can connect to the graphic console from another host or connect to the console using the following command:
    virsh -c qemu+tls://Test/system console HostedEngine
    If you need to reboot the VM you will need to start it manually using the command:
    hosted-engine --vm-start
    You can then set a temporary password using the command:
    hosted-engine --add-console-password
    The VM has been started.  Install the OS and shut down or reboot it.  To continue please make a selection:
             
      (1) Continue setup - VM installation is complete
      (2) Reboot the VM and restart installation
      (3) Abort setup
      (4) Destroy VM and abort setup
             
      (1, 2, 3, 4)[1]:
    Using the naming convention of this procedure, connect to the virtual machine using VNC with the following command:
    /usr/bin/remote-viewer vnc://hosted_engine_1.example.com:5900
  11. Installing the Virtual Machine Operating System

    Connect to Manager virtual machine and install a Red Hat Enterprise Linux 7 operating system.
  12. Synchronizing the Host and the Manager

    Return to the host and continue the hosted-engine deployment script by selecting option 1:
    (1) Continue setup - VM installation is complete
    Waiting for VM to shut down...
    [ INFO  ] Creating VM
    You can now connect to the VM with the following command:
          /usr/bin/remote-viewer vnc://localhost:5900
    Use temporary password "3477XXAM" to connect to vnc console.
    Please note that in order to use remote-viewer you need to be able to run graphical applications.
    This means that if you are using ssh you have to supply the -Y flag (enables trusted X11 forwarding).
    Otherwise you can run the command from a terminal in your preferred desktop environment.
    If you cannot run graphical applications you can connect to the graphic console from another host or connect to the console using the following command:
    virsh -c qemu+tls://Test/system console HostedEngine
    If you need to reboot the VM you will need to start it manually using the command:
    hosted-engine --vm-start
    You can then set a temporary password using the command:
    hosted-engine --add-console-password
    Please install and setup the engine in the VM.
    You may also be interested in subscribing to "agent" RHN/Satellite channel and installing rhevm-guest-agent-common package in the VM.
    To continue make a selection from the options below:
      (1) Continue setup - engine installation is complete
      (2) Power off and restart the VM
      (3) Abort setup
      (4) Destroy VM and abort setup
             
      (1, 2, 3, 4)[1]:
  13. Installing the Manager

    Connect to the new Manager virtual machine, register it with Red Hat Subscription Management, and enable the required repositories. See Subscribing to the Required Entitlements in the Installation Guide.
    Ensure the latest versions of all installed packages are in use, and install the rhevm packages.
    # yum update

    Note

    Reboot the machine if any kernel related packages have been updated.
    # yum install rhevm
After the packages have completed installation, you will be able to continue with restoring the self-hosted engine Manager.

6.2.2. Restoring the Self-Hosted Engine Manager

The following procedure outlines how to use the engine-backup tool to automate the restore of the configuration settings and database content for a backed-up self-hosted engine Manager virtual machine and Data Warehouse. The procedure only applies to components that were configured automatically during the initial engine-setup. If you configured the database(s) manually during engine-setup, follow the instructions at Section 6.2.3, “Restoring the Self-Hosted Engine Manager Manually” to restore the back-up environment manually.

Procedure 6.5. Restoring the Self-Hosted Engine Manager

  1. Secure copy the backup files to the new Manager virtual machine. This example copies the files from a network storage server to which the files were copied in Section 6.1, “Backing up the Self-Hosted Engine Manager Virtual Machine”. In this example, Storage.example.com is the fully qualified domain name of the storage server, /backup/EngineBackupFiles is the designated file path for the backup files on the storage server, and /backup/ is the path to which the files will be copied on the new Manager.
    # scp -p Storage.example.com:/backup/EngineBackupFiles /backup/
  2. Use the engine-backup tool to restore a complete backup.
    • If you are only restoring the Manager, run:
      # engine-backup --mode=restore --file=file_name --log=log_file_name --provision-db --restore-permissions
    • If you are restoring the Manager and Data Warehouse, run:
      # engine-backup --mode=restore --file=file_name --log=log_file_name --provision-db --provision-dwh-db --restore-permissions
    If successful, the following output displays:
    You should now run engine-setup.
    Done.
  3. Configure the restored Manager virtual machine. This process identifies the existing configuration settings and database content. Confirm the settings. Upon completion, the setup provides an SSH fingerprint and an internal Certificate Authority hash.
    # engine-setup
    [ INFO  ] Stage: Initializing
    [ INFO  ] Stage: Environment setup
    Configuration files: ['/etc/ovirt-engine-setup.conf.d/10-packaging.conf', '/etc/ovirt-engine-setup.conf.d/20-setup-ovirt-post.conf']
    Log file: /var/log/ovirt-engine/setup/ovirt-engine-setup-20140304075238.log
    Version: otopi-1.1.2 (otopi-1.1.2-1.el6ev)
    [ INFO  ] Stage: Environment packages setup
    [ INFO  ] Yum Downloading: rhel-65-zstream/primary_db 2.8 M(70%)
    [ INFO  ] Stage: Programs detection
    [ INFO  ] Stage: Environment setup
    [ INFO  ] Stage: Environment customization
             
              --== PACKAGES ==--
             
    [ INFO  ] Checking for product updates...
    [ INFO  ] No product updates found
             
              --== NETWORK CONFIGURATION ==--
             
    Setup can automatically configure the firewall on this system.
    Note: automatic configuration of the firewall may overwrite current settings.
    Do you want Setup to configure the firewall? (Yes, No) [Yes]: 
    [ INFO  ] iptables will be configured as firewall manager.
             
              --== DATABASE CONFIGURATION ==--
             
             
              --== OVIRT ENGINE CONFIGURATION ==--
             
              Skipping storing options as database already prepared
             
              --== PKI CONFIGURATION ==--
             
              PKI is already configured
             
              --== APACHE CONFIGURATION ==--
             
             
              --== SYSTEM CONFIGURATION ==--
             
             
              --== END OF CONFIGURATION ==--
             
    [ INFO  ] Stage: Setup validation
    [ INFO  ] Cleaning stale zombie tasks
             
              --== CONFIGURATION PREVIEW ==--
             
              Database name                      : engine
              Database secured connection        : False
              Database host                      : X.X.X.X
              Database user name                 : engine
              Database host name validation      : False
              Database port                      : 5432
              NFS setup                          : True
              Firewall manager                   : iptables
              Update Firewall                    : True
              Configure WebSocket Proxy          : True
              Host FQDN                          : Manager.example.com
              NFS mount point                    : /var/lib/exports/iso
              Set application as default page    : True
              Configure Apache SSL               : True
             
              Please confirm installation settings (OK, Cancel) [OK]:
  4. Removing the Host from the Restored Environment

    If the deployment of the restored self-hosted engine is on new hardware that has a unique name not present in the backed-up engine, skip this step. This step is only applicable to deployments occurring on the failover host, hosted_engine_1. Because this host was present in the environment at time the backup was created, it maintains a presence in the restored engine and must first be removed from the environment before final synchronization can take place.
    1. Log in to the Administration Portal.
    2. Click the Hosts tab. The failover host, hosted_engine_1, will be in maintenance mode and without a virtual load, as this was how it was prepared for the backup.
    3. Click Remove.
    4. Click Ok.

    Note

    If the host you are trying to remove becomes non-operational, see Section 6.2.4, “Removing Non-Operational Hosts from a Restored Self-Hosted Engine Environment” for instructions on how to force the removal of a host.
  5. Synchronizing the Host and the Manager

    Return to the host and continue the hosted-engine deployment script by selecting option 1:
    (1) Continue setup - engine installation is complete
    [ INFO  ] Engine replied: DB Up!Welcome to Health Status!
    [ INFO  ] Waiting for the host to become operational in the engine. This may take several minutes...
    [ INFO  ] Still waiting for VDSM host to become operational...
    At this point, hosted_engine_1 will become visible in the Administration Portal with Installing and Initializing states before entering a Non Operational state. The host will continue to wait for the VDSM host to become operational until it eventually times out. This happens because another host in the environment maintains the Storage Pool Manager (SPM) role and hosted_engine_1 cannot interact with the storage domain because the SPM host is in a Non Responsive state. When this process times out, you are prompted to shut down the virtual machine to complete the deployment. When deployment is complete, the host can be manually placed into maintenance mode and activated through the Administration Portal.
    [ INFO  ] Still waiting for VDSM host to become operational...
    [ ERROR ] Timed out while waiting for host to start. Please check the logs.
    [ ERROR ] Unable to add hosted_engine_2 to the manager
              Please shutdown the VM allowing the system to launch it as a monitored service.
              The system will wait until the VM is down.
  6. Shut down the new Manager virtual machine.
    # shutdown -h now
  7. Return to the host to confirm it has detected that the Manager virtual machine is down.
    [ INFO  ] Enabling and starting HA services
              Hosted Engine successfully set up
    [ INFO  ] Stage: Clean up
    [ INFO  ] Stage: Pre-termination
    [ INFO  ] Stage: Termination
    
  8. Activate the host.
    1. Log in to the Administration Portal.
    2. Click the Hosts tab.
    3. Select hosted_engine_1 and click ManagementMaintenance. The host may take several minutes before it enters maintenance mode.
    4. Click ManagementActivate.
    Once active, hosted_engine_1 immediately contends for SPM, and the storage domain and data center become active.
  9. Migrate virtual machines to the active host by manually fencing the Non Responsive hosts. In the Administration Portal, right-click the hosts and select Confirm 'Host has been Rebooted'.
    Any virtual machines that were running on that host at the time of the backup will now be removed from that host, and move from an Unknown state to a Down state. These virtual machines can now be run on hosted_engine_1. The host that was fenced can now be forcefully removed using the REST API.
The environment has now been restored to a point where hosted_engine_1 is active and is able to run virtual machines in the restored environment. The remaining self-hosted engine nodes in Non Operational state can now be removed by following the steps in Section 6.2.4, “Removing Non-Operational Hosts from a Restored Self-Hosted Engine Environment” and then re-installed into the environment by following the steps in Chapter 7, Installing Additional Hosts to a Self-Hosted Environment.

Note

If the Manager database is restored successfully, but the Manager virtual machine appears to be Down and cannot be migrated to another self-hosted engine node, you can enable a new Manager virtual machine and remove the dead Manager virtual machine from the environment by following the steps provided in https://access.redhat.com/solutions/1517683.

6.2.3. Restoring the Self-Hosted Engine Manager Manually

The following procedure outlines how to manually restore the configuration settings and database content for a backed-up self-hosted engine Manager virtual machine.

Procedure 6.6. Restoring the Self-Hosted Engine Manager

  1. Manually create an empty database to which the database content in the backup can be restored. The following steps must be performed on the machine where the database is to be hosted.
    1. If the database is to be hosted on a machine other than the Manager virtual machine, install the postgresql-server package. This step is not required if the database is to be hosted on the Manager virtual machine because this package is included with the rhevm package.
      # yum install postgresql-server
    2. Initialize the postgresql database, start the postgresql service, and ensure this service starts on boot:
      # postgresql-setup initdb
      # systemctl start postgresql.service
      # systemctl enable postgresql.service
    3. Enter the postgresql command line:
      # su postgres
      $ psql
    4. Create the engine user:
      postgres=# create role engine with login encrypted password 'password';
      If you are also restoring Data Warehouse, create the ovirt_engine_history user on the relevant host:
      postgres=# create role ovirt_engine_history with login encrypted password 'password';
    5. Create the new database:
      postgres=# create database database_name owner engine template template0 encoding 'UTF8' lc_collate 'en_US.UTF-8' lc_ctype 'en_US.UTF-8';
      If you are also restoring the Data Warehouse, create the database on the relevant host:
      postgres=# create database database_name owner ovirt_engine_history template template0 encoding 'UTF8' lc_collate 'en_US.UTF-8' lc_ctype 'en_US.UTF-8';
    6. Exit the postgresql command line and log out of the postgres user:
      postgres=# \q
      $ exit
    7. Edit the /var/lib/pgsql/data/pg_hba.conf file as follows:
      • For each local database, replace the existing directives in the section starting with local at the bottom of the file with the following directives:
        host    database_name    user_name    0.0.0.0/0  md5
        host    database_name    user_name    ::0/0      md5
      • For each remote database:
        • Add the following line immediately underneath the line starting with Local at the bottom of the file, replacing X.X.X.X with the IP address of the Manager:
          host    database_name    user_name    X.X.X.X/32   md5
        • Allow TCP/IP connections to the database. Edit the /var/lib/pgsql/data/postgresql.conf file and add the following line:
          listen_addresses='*'
          This example configures the postgresql service to listen for connections on all interfaces. You can specify an interface by giving its IP address.
        • Open the default port used for PostgreSQL database connections, and save the updated firewall rules:
          # iptables -I INPUT 5 -p tcp -s Manager_IP_Address --dport 5432 -j ACCEPT
          # service iptables save
    8. Restart the postgresql service:
      # systemctl restart postgresql.service
  2. Secure copy the backup files to the new Manager virtual machine. This example copies the files from a network storage server to which the files were copied in Section 6.1, “Backing up the Self-Hosted Engine Manager Virtual Machine”. In this example, Storage.example.com is the fully qualified domain name of the storage server, /backup/EngineBackupFiles is the designated file path for the backup files on the storage server, and /backup/ is the path to which the files will be copied on the new Manager.
    # scp -p Storage.example.com:/backup/EngineBackupFiles /backup/
  3. Restore a complete backup or a database-only backup with the --change-db-credentials parameter to pass the credentials of the new database. The database_location for a database local to the Manager is localhost.

    Note

    The following examples use a --*password option for each database without specifying a password, which will prompt for a password for each database. Passwords can be supplied for these options in the command itself, however this is not recommended as the password will then be stored in the shell history. Alternatively, --*passfile=password_file options can be used for each database to securely pass the passwords to the engine-backup tool without the need for interactive prompts.
    • Restore a complete backup:
      # engine-backup --mode=restore --file=file_name --log=log_file_name --change-db-credentials --db-host=database_location --db-name=database_name --db-user=engine --db-password
      If Data Warehouse is also being restored as part of the complete backup, include the revised credentials for the additional database:
      engine-backup --mode=restore --file=file_name --log=log_file_name --change-db-credentials --db-host=database_location --db-name=database_name --db-user=engine --db-password --change-dwh-db-credentials --dwh-db-host=database_location --dwh-db-name=database_name --dwh-db-user=ovirt_engine_history --dwh-db-password
    • Restore a database-only backup restoring the configuration files and the database backup:
      # engine-backup --mode=restore --scope=files --scope=db --file=file_name --log=file_name --change-db-credentials --db-host=database_location --db-name=database_name --db-user=engine --db-password
      The example above restores a backup of the Manager database.
      # engine-backup --mode=restore --scope=files --scope=dwhdb --file=file_name --log=file_name --change-dwh-db-credentials --dwh-db-host=database_location --dwh-db-name=database_name --dwh-db-user=ovirt_engine_history --dwh-db-password
      The example above restores a backup of the Data Warehouse database.
    If successful, the following output displays:
    You should now run engine-setup.
    Done.
  4. Configure the restored Manager virtual machine. This process identifies the existing configuration settings and database content. Confirm the settings. Upon completion, the setup provides an SSH fingerprint and an internal Certificate Authority hash.
    # engine-setup
    [ INFO  ] Stage: Initializing
    [ INFO  ] Stage: Environment setup
    Configuration files: ['/etc/ovirt-engine-setup.conf.d/10-packaging.conf', '/etc/ovirt-engine-setup.conf.d/20-setup-ovirt-post.conf']
    Log file: /var/log/ovirt-engine/setup/ovirt-engine-setup-20140304075238.log
    Version: otopi-1.1.2 (otopi-1.1.2-1.el6ev)
    [ INFO  ] Stage: Environment packages setup
    [ INFO  ] Yum Downloading: rhel-65-zstream/primary_db 2.8 M(70%)
    [ INFO  ] Stage: Programs detection
    [ INFO  ] Stage: Environment setup
    [ INFO  ] Stage: Environment customization
             
              --== PACKAGES ==--
             
    [ INFO  ] Checking for product updates...
    [ INFO  ] No product updates found
             
              --== NETWORK CONFIGURATION ==--
             
    Setup can automatically configure the firewall on this system.
    Note: automatic configuration of the firewall may overwrite current settings.
    Do you want Setup to configure the firewall? (Yes, No) [Yes]: 
    [ INFO  ] iptables will be configured as firewall manager.
             
              --== DATABASE CONFIGURATION ==--
             
             
              --== OVIRT ENGINE CONFIGURATION ==--
             
              Skipping storing options as database already prepared
             
              --== PKI CONFIGURATION ==--
             
              PKI is already configured
             
              --== APACHE CONFIGURATION ==--
             
             
              --== SYSTEM CONFIGURATION ==--
             
             
              --== END OF CONFIGURATION ==--
             
    [ INFO  ] Stage: Setup validation
    [ INFO  ] Cleaning stale zombie tasks
             
              --== CONFIGURATION PREVIEW ==--
             
              Database name                      : engine
              Database secured connection        : False
              Database host                      : X.X.X.X
              Database user name                 : engine
              Database host name validation      : False
              Database port                      : 5432
              NFS setup                          : True
              Firewall manager                   : iptables
              Update Firewall                    : True
              Configure WebSocket Proxy          : True
              Host FQDN                          : Manager.example.com
              NFS mount point                    : /var/lib/exports/iso
              Set application as default page    : True
              Configure Apache SSL               : True
             
              Please confirm installation settings (OK, Cancel) [OK]:
  5. Removing the Host from the Restored Environment

    If the deployment of the restored self-hosted engine is on new hardware that has a unique name not present in the backed-up engine, skip this step. This step is only applicable to deployments occurring on the failover host, hosted_engine_1. Because this host was present in the environment at time the backup was created, it maintains a presence in the restored engine and must first be removed from the environment before final synchronization can take place.
    1. Log in to the Administration Portal.
    2. Click the Hosts tab. The failover host, hosted_engine_1, will be in maintenance mode and without a virtual load, as this was how it was prepared for the backup.
    3. Click Remove.
    4. Click Ok.
  6. Synchronizing the Host and the Manager

    Return to the host and continue the hosted-engine deployment script by selecting option 1:
    (1) Continue setup - engine installation is complete
    [ INFO  ] Engine replied: DB Up!Welcome to Health Status!
    [ INFO  ] Waiting for the host to become operational in the engine. This may take several minutes...
    [ INFO  ] Still waiting for VDSM host to become operational...
    At this point, hosted_engine_1 will become visible in the Administration Portal with Installing and Initializing states before entering a Non Operational state. The host will continue to wait for the VDSM host to become operational until it eventually times out. This happens because another host in the environment maintains the Storage Pool Manager (SPM) role and hosted_engine_1 cannot interact with the storage domain because the SPM host is in a Non Responsive state. When this process times out, you are prompted to shut down the virtual machine to complete the deployment. When deployment is complete, the host can be manually placed into maintenance mode and activated through the Administration Portal.
    [ INFO  ] Still waiting for VDSM host to become operational...
    [ ERROR ] Timed out while waiting for host to start. Please check the logs.
    [ ERROR ] Unable to add hosted_engine_2 to the manager
              Please shutdown the VM allowing the system to launch it as a monitored service.
              The system will wait until the VM is down.
  7. Shut down the new Manager virtual machine.
    # shutdown -h now
  8. Return to the host to confirm it has detected that the Manager virtual machine is down.
    [ INFO  ] Enabling and starting HA services
              Hosted Engine successfully set up
    [ INFO  ] Stage: Clean up
    [ INFO  ] Stage: Pre-termination
    [ INFO  ] Stage: Termination
    
  9. Activate the host.
    1. Log in to the Administration Portal.
    2. Click the Hosts tab.
    3. Select hosted_engine_1 and click ManagementMaintenance. The host may take several minutes before it enters maintenance mode.
    4. Click ManagementActivate.
    Once active, hosted_engine_1 immediately contends for SPM, and the storage domain and data center become active.
  10. Migrate virtual machines to the active host by manually fencing the Non Responsive hosts. In the Administration Portal, right-click the hosts and select Confirm 'Host has been Rebooted'.
    Any virtual machines that were running on that host at the time of the backup will now be removed from that host, and move from an Unknown state to a Down state. These virtual machines can now be run on hosted_engine_1. The host that was fenced can now be forcefully removed using the REST API.
The environment has now been restored to a point where hosted_engine_1 is active and is able to run virtual machines in the restored environment. The remaining self-hosted engine nodes in Non Operational state can now be removed by following the steps in Section 6.2.4, “Removing Non-Operational Hosts from a Restored Self-Hosted Engine Environment” and then re-installed into the environment by following the steps in Chapter 7, Installing Additional Hosts to a Self-Hosted Environment.

Note

If the Manager database is restored successfully, but the Manager virtual machine appears to be Down and cannot be migrated to another self-hosted engine node, you can enable a new Manager virtual machine and remove the dead Manager virtual machine from the environment by following the steps provided in https://access.redhat.com/solutions/1517683.

6.2.4. Removing Non-Operational Hosts from a Restored Self-Hosted Engine Environment

Once a host has been fenced in the Administration Portal, it can be forcefully removed with a REST API request. This procedure will use cURL, a command line interface for sending requests to HTTP servers. Most Linux distributions include cURL. This procedure will connect to the Manager virtual machine to perform the relevant requests.
  1. Fencing the Non-Operational Host

    In the Administration Portal, right-click the hosts and select Confirm 'Host has been Rebooted'.
    Any virtual machines that were running on that host at the time of the backup will now be removed from that host, and move from an Unknown state to a Down state. The host that was fenced can now be forcefully removed using the REST API.
  2. Retrieving the Manager Certificate Authority

    Connect to the Manager virtual machine and use the command line to perform the following requests with cURL.
    Use a GET request to retrieve the Manager Certificate Authority (CA) certificate for use in all future API requests. In the following example, the --output option is used to designate the file hosted-engine.ca as the output for the Manager CA certificate. The --insecure option means that this initial request will be without a certificate.
    # curl --output hosted-engine.ca --insecure https://[Manager.example.com]/ca.crt
  3. Retrieving the GUID of the Host to be Removed

    Use a GET request on the hosts collection to retrieve the Global Unique Identifier (GUID) for the host to be removed. The following example includes the Manager CA certificate file, and uses the admin@internal user for authentication, the password for which will be prompted once the command is executed.
    # curl --request GET --cacert hosted-engine.ca --user admin@internal https://[Manager.example.com]/api/hosts
    This request returns the details of all of the hosts in the environment. The host GUID is a hexadecimal string associated with the host name. For more information on the Red Hat Virtualization REST API, see the Red Hat Virtualization REST API Guide.
  4. Removing the Fenced Host

    Use a DELETE request using the GUID of the fenced host to remove the host from the environment. In addition to the previously used options this example specifies headers to specify that the request is to be sent and returned using eXtensible Markup Language (XML), and the body in XML that sets the force action to be true.
    curl --request DELETE --cacert hosted-engine.ca --user admin@internal --header "Content-Type: application/xml" --header "Accept: application/xml" --data "<action><force>true</force></action>" https://[Manager.example.com]/api/hosts/ecde42b0-de2f-48fe-aa23-1ebd5196b4a5
    This DELETE request can be used to remove every fenced host in the self-hosted engine environment, as long as the appropriate GUID is specified.
  5. Removing the Self-Hosted Engine Configuration from the Host

    Remove the host's self-hosted engine configuration so it can be reconfigured when the host is re-installed to a self-hosted engine environment.
    Log in to the host and remove the configuration file:
    # rm /etc/ovirt-hosted-engine/hosted-engine.conf
The host can now be re-installed to the self-hosted engine environment.