Chapter 2. Restoring the undercloud

Procedure

1. Log into your undercloud as the root user.

2. Register your system with the Content Delivery Network, entering your Customer Portal user name and password when prompted:

   [root@director ~]# subscription-manager register

3. Attach the Red Hat OpenStack Platform entitlement:

   [root@director ~]# subscription-manager attach --pool=Valid-Pool-Number-123456

4. Disable all default repositories, and then enable the required Red Hat Enterprise Linux repositories:

   [root@director ~]# subscription-manager repos --disable=*
   [root@director ~]# subscription-manager repos --enable=rhel-7-server-rpms --enable=rhel-7-server-extras-rpms --enable=rhel-7-server-rh-common-rpms --enable=rhel-ha-for-rhel-7-server-rpms --enable=rhel-7-server-openstack-10-rpms

5. Perform an update on your system to make sure you have the latest base system packages:

   [root@director ~]# yum update -y
   [root@director ~]# reboot

6. Ensure the time on your undercloud is synchronized. For example:

   [root@director ~]# yum install -y ntp
   [root@director ~]# systemctl start ntpd
   [root@director ~]# systemctl enable ntpd
   [root@director ~]# ntpdate pool.ntp.org
   [root@director ~]# systemctl restart ntpd

7. Copy the undercloud backup archive to the undercloud’s root directory. The following steps use undercloud-backup-$TIMESTAMP.tar as the filename, where $TIMESTAMP is a Bash variable for the timestamp on the archive.

8. Install the database server and client tools:

   [root@director ~]# yum install -y mariadb mariadb-server

9. Start the database:

   [root@director ~]# systemctl start mariadb
   [root@director ~]# systemctl enable mariadb

10. Increase the allowed packets to accommodate the size of our database backup:

    [root@director ~]# mysql -uroot -e"set global max_allowed_packet = 1073741824;"

11. Extract the database and database configuration from the archive:

    [root@director ~]# tar -xvC / -f undercloud-backup-$TIMESTAMP.tar etc/my.cnf.d/*server*.cnf
    [root@director ~]# tar -xvC / -f undercloud-backup-$TIMESTAMP.tar root/undercloud-all-databases.sql

12. Restore the database backup:

    [root@director ~]# mysql -u root < /root/undercloud-all-databases.sql

13. Extract a temporary version of the root configuration file:

    [root@director ~]# tar -xvf undercloud-backup-$TIMESTAMP.tar root/.my.cnf

14. Get the old root database password:

    [root@director ~]# OLDPASSWORD=$(sudo cat root/.my.cnf | grep -m1 password | cut -d'=' -f2 | tr -d "'")

15. Reset the root database password:

    [root@director ~]# mysqladmin -u root password "$OLDPASSWORD"

16. Move the root configuration file from the temporary directory to the root directory:

    [root@director ~]# mv ~/root/.my.cnf ~/.
    [root@director ~]# rmdir ~/root

17. Get a list of old user permissions:

    [root@director ~]# mysql -e 'select host, user, password from mysql.user;'

18. Remove the old user permissions for each host listed. For example:

    [root@director ~]# HOST="192.0.2.1"
    [root@director ~]# USERS=$(mysql -Nse "select user from mysql.user WHERE user != \"root\" and host = \"$HOST\";" | uniq | xargs)
    [root@director ~]# for USER in $USERS ; do mysql -e "drop user \"$USER\"@\"$HOST\"" || true ;done
    [root@director ~]# mysql -e 'flush privileges'

    Perform this for all users accessing through the host IP and any host ("%")

19. Restart the database:

    [root@director ~]# systemctl restart mariadb

20. Create the stack user:

    [root@director ~]# useradd stack

21. Set a password for the user:

    [root@director ~]# passwd stack

22. Disable password requirements when using sudo:

    [root@director ~]# echo "stack ALL=(root) NOPASSWD:ALL" | tee -a /etc/sudoers.d/stack
    [root@director ~]# chmod 0440 /etc/sudoers.d/stack

23. Restore the stack user home directory:

    # tar -xvC / -f undercloud-backup-$TIMESTAMP.tar home/stack

24. Install the policycoreutils-python package:

    [root@director ~]# yum -y install policycoreutils-python

25. Install the openstack-glance package and restore its data and file permissions:

    [root@director ~]# yum install -y openstack-glance
    [root@director ~]# tar --xattrs -xvC / -f undercloud-backup-$TIMESTAMP.tar var/lib/glance/images
    [root@director ~]# chown -R glance: /var/lib/glance/images
    [root@director ~]# restorecon -R /var/lib/glance/images

26. Install the openstack-swift package and restore its data and file permissions:

    [root@director ~]# yum install -y openstack-swift
    [root@director ~]# tar --xattrs -xvC / -f undercloud-backup-$TIMESTAMP.tar srv/node
    [root@director ~]# chown -R swift: /srv/node
    [root@director ~]# restorecon -R /srv/node

27. Install the openstack-keystone package and restore its configuration data:

    [root@director ~]# yum -y install openstack-keystone
    [root@director ~]# tar -xvC / -f undercloud-backup-$TIMESTAMP.tar etc/keystone
    [root@director ~]# restorecon -R /etc/keystone

28. Install the openstack-heat and restore configuration:

    [root@director ~]# yum install -y openstack-heat*
    [root@director ~]# tar -xvC / -f undercloud-backup-$TIMESTAMP.tar etc/heat
    [root@director ~]# restorecon -R /etc/heat

29. Install puppet and restore its configuration data:

    [root@director ~]# yum install -y puppet hiera
    [root@director ~]# tar -xvC / -f undercloud-backup-$TIMESTAMP.tar etc/puppet/hieradata/

30. If using SSL in the undercloud, refresh the CA certificates:

    [root@director ~]# tar -xvC / -f undercloud-backup-$TIMESTAMP.tar etc/pki/instack-certs/undercloud.pem
    [root@director ~]# tar -xvC / -f undercloud-backup-$TIMESTAMP.tar etc/pki/ca-trust/source/anchors/*
    [root@director ~]# restorecon -R /etc/pki
    [root@director ~]# semanage fcontext -a -t etc_t "/etc/pki/instack-certs(/.*)?"
    [root@director ~]# restorecon -R /etc/pki/instack-certs
    [root@director ~]# update-ca-trust extract

31. Switch to the stack user:

    [root@director ~]# su - stack
    [stack@director ~]$

32. Install the python-tripleoclient package:

    $ sudo yum install -y python-tripleoclient

33. Run the undercloud installation command. Ensure to run it in the stack user’s home directory:

    [stack@director ~]$ openstack undercloud install

34. Wait until the install completes. The undercloud automatically restores its connection to the overcloud. The nodes will continue to poll OpenStack Orchestration (heat) for pending tasks.