Back Up and Restore the Director Undercloud
Back up and restore the director undercloud
Abstract
Chapter 1. About This Guide
Red Hat is currently reviewing the information and procedures provided in this guide for this release.
This document is based on the Red Hat OpenStack Platform 10 document, available at https://access.redhat.com/documentation/en-us/red_hat_openstack_platform/?version=10.
If you require assistance for Red Hat OpenStack Platform 11, please contact Red Hat support.
Chapter 2. Back Up and Restore the Undercloud
This guide describes how to back up the undercloud used in the Red Hat OpenStack Platform director. The undercloud is usually a single physical node (although high availability options exist using a two-node pacemaker cluster that runs director in a VM) that is used to deploy and manage your OpenStack environment.
2.1. Backup Considerations
Formulate a robust back up and recovery policy in order to minimize data loss and system downtime. When determining your back up strategy, you will need to answer the following questions:
- How quickly will you need to recover from data loss? If you cannot have data loss at all, you should include high availability in your deployment strategy, in addition to using backups. You’ll need to consider how long it will take to obtain the physical backup media (including from an offsite location, if used), and how many tape drives are available for restore operations.
- How many backups should you keep? You will need to consider legal and regulatory requirements that affect how long you are expected to store data.
- Should your backups be kept off-site? Storing your backup media offsite will help mitigate the risk of catastrophe befalling your physical location.
- How often should backups be tested? A robust back up strategy will include regular restoration tests of backed up data. This can help validate that the correct data is still being backed up, and that no corruption is being introduced during the back up or restoration processes. These drills should assume that they are being performed under actual disaster recovery conditions.
- What will be backed up? The following sections describe database and file-system backups for components, as well as information on recovering backups.
2.2. High Availability of the Undercloud node
You are free to consider your preferred high availability (HA) options for the Undercloud node; Red Hat does not prescribe any particular requirements for this. For example, you might consider running your Undercloud node as a highly available virtual machine within Red Hat Enterprise Virtualization (RHEV). You might also consider using physical nodes with Pacemaker providing HA for the required services.
When approaching high availability for your Undercloud node, you should consult the documentation and good practices of the solution you decide works best for your environment.
2.3. Back Up the Undercloud
A full undercloud backup includes the following databases and files:
- All MariaDB databases on the undercloud node
- MariaDB configuration file on the undercloud (so that you can accurately restore databases)
- All glance image data in /var/lib/glance/images
- All swift data in /srv/node
- All data in the stack user home directory: /home/stack
The undercloud SSL certificates:
- /etc/pki/ca-trust/source/anchors/ca.crt.pem
- /home/stack /etc/pki/instack-certs/undercloud.pem
Run the following commands as the root user to dump the data from the undercloud node to a file named undercloud-backup-[timestamp].tar.gz.
Confirm that you have sufficient disk space available before performing the backup process. The tarball can be expected to be at least 3.5 GB, but this is likely to be larger.
# mysqldump --opt --all-databases > /root/undercloud-all-databases.sql # tar --xattrs -czf undercloud-backup-`date +%F`.tar.gz /root/undercloud-all-databases.sql /etc/my.cnf.d/server.cnf /var/lib/glance/images /srv/node /home/stack /etc/pki/instack-certs/undercloud.pem /etc/pki/ca-trust/source/anchors/ca.crt.pem
2.4. Validate the Completed Backup
You can validate the success of the completed back up process by running and validating the restore process. See the next section for further details on restoring from backup.
Chapter 3. Restore
This section describes how to restore the undercloud used in the Red Hat OpenStack Platform Director.
3.1. Restore the Undercloud
The following restore process assumes you are recovering a failed undercloud node, and you need to reinstall it from scratch. It assumes that the hardware layout is identical, and the hostname and undercloud settings of the machine will also be identical.
Once the machine is installed and is in a clean state, re-enable all the subscriptions/repositories needed to install and run director. Run the following commands as the root user:
1. Install the mariadb server:
# yum install -y mariadb-server
2. Restore the MariaDB configuration file and database backup, then start the MariaDB server and load the backup data:
a. As the root user, restore the MariaDB files:
# tar -xzC / -f undercloud-backup-$DATE.tar.gz etc/my.cnf.d/server.cnf # tar -xzC / -f undercloud-backup-$DATE.tar.gz root/undercloud-all-databases.sql
b. Edit /etc/my.cnf.d/server.cnf and comment out the bind-address entry.
c. Start the mariadb service and temporarily update the max_allowed_packet setting:
# systemctl start mariadb # mysql -uroot -e"set global max_allowed_packet = 16777216;" # cat /root/undercloud-all-databases.sql | mysql
d. Clean up certain permissions (to be recreated later):
# for i in ceilometer glance heat ironic keystone neutron nova;do mysql -e "drop user $i";done # mysql -e 'flush privileges'
3. Create the stack user account:
# sudo useradd stack # sudo passwd stack # specify a password # echo "stack ALL=(root) NOPASSWD:ALL" | sudo tee -a /etc/sudoers.d/stack # sudo chmod 0440 /etc/sudoers.d/stack
4. Restore the stack user home directory:
# tar -xzC / -f undercloud-backup-$DATE.tar.gz home/stack
5. Install the swift and glance base packages, and then restore their data:
# yum install -y openstack-glance openstack-swift # tar --xattrs -xzC / -f undercloud-backup-$DATE.tar.gz srv/node var/lib/glance/images
6. Confirm the data is owned by the correct user:
# chown -R swift: /srv/node # chown -R glance: /var/lib/glance/images
7. Restore your undercloud SSL certificates:
# tar -xzC / -f undercloud-backup-$DATE.tar.gz etc/pki/instack-certs/undercloud.pem # tar -xzC / -f undercloud-backup-$DATE.tar.gz etc/pki/ca-trust/source/anchors/ca.crt.pem
8. Re-run the undercloud installation as the stack user, making sure to run it in the stack user home directory:
# su - stack $ sudo yum install -y python-tripleoclient
9. Confirm that the hostname is correctly set in /etc/hosts.
10. Reinstall the undercloud:
$ openstack undercloud install
3.2. Reconnect the restored undercloud to the overcloud
Having completed the steps above, the undercloud can be expected to automatically restore its connection to the overcloud. The nodes will continue to poll Orchestration (heat) for pending tasks, using a simple HTTP request issued every few seconds.
3.3. Validate the Completed Restore
Use the following commands to perform a healthcheck of your newly restored environment:
3.3.1. Check Identity Service (Keystone) Operation
This step validates Identity Service operations by querying for a list of users.
# source overcloudrc # openstack user list
When run from the controller, the output of this command should include a list of users created in your environment. This action demonstrates that keystone is running and successfully authenticating user requests. For example:
# openstack user list +----------------------------------+------------+---------+----------------------+ | id | name | enabled | email | +----------------------------------+------------+---------+----------------------+ | 9e47bb53bb40453094e32eccce996828 | admin | True | root@localhost | | 9fe2466f88cc4fa0ba69e59b47898829 | ceilometer | True | ceilometer@localhost | | 7a40d944e55d422fa4e85daf47e47c42 | cinder | True | cinder@localhost | | 3d2ed97538064f258f67c98d1912132e | demo | True | | | 756e73a5115d4e9a947d8aadc6f5ac22 | glance | True | glance@localhost | | f0d1fcee8f9b4da39556b78b72fdafb1 | neutron | True | neutron@localhost | | e9025f3faeee4d6bb7a057523576ea19 | nova | True | nova@localhost | | 65c60b1278a0498980b2dc46c7dcf4b7 | swift | True | swift@localhost | +----------------------------------+------------+---------+----------------------+
3.3.2. Check the OpenStack Services
Run the openstack-status command to view the status of OpenStack services:
# openstack-status
