Network Edition Disaster Recovery
This article describes the steps to replace a failed server in a version 4.5.x network edition single-server ZCS configuration, (should be mostly applicable to version 5.x as well).
Important: The ZCS release you install on the new server must be the same release as installed on the old server. The server can have a different operating system.
The new server hardware must meet the requirements described in the Installation Prerequisites section of the ZCS Single Server Installation Guide. Install the new operating system, making any necessary OS configuration modifications as described in the installation guide.
Disaster Recovery - Changing Servers
You do the following to restore to a new server:
- Prepare the new server
- Block client access to the old server’s IP address with firewall rules
- Mount any volumes that were in use on the older server
- Delete the MySQL data that is set up in the initial installation of ZCS
- Copy the backup files to the new server
- Run zmrestoreldap to restore the global LDAP data
- Run zmrestoreoffline to restore account data from the backup sessions
- Prepare and run a new backup
Old Server Status
Two scenarios for disaster recovery are the server has died and the ZCS files cannot be accessed, or ZCS is still running, but the server needs to be replaced.
If the server is not running:
- Block client access to the server IP address with firewall rules.
- Find the latest full ZCS backup session to use.
If ZCS is still running, to prepare the move to the new server:
- Block client access to the server’s IP address with firewall rules.
- Run a full backup of the old service, or if the backup is recent, run an incremental backup to get the most current incremental backup session.
- Run zmcontrol stop, to stop ZCS. In order to restore to the most current state, no new mail should be received after the last incremental backup has run.
- Change the hostname and IP address on the old server to something else. Do not turn off the server.
Preparing the New Server
Before you begin, make sure that the new server is correctly configured with the IP address and hostname and that ZCS is installed and configured with the same domain, hostname, passwords, etc. as the previous server. See the Single-Server Installation Guide for more information about preparing the server. Before you begin to install ZCS, note the information you need from the old server including: admin account name and password, spam training and non-spam training user account names, exact domain name, and the global document account name.
Installing ZCS on new server
- Ensure that the old hostname and MX DNS records resolve to the new server
- If the new server was used for testing in the past then there may be remnants of previous installations that need to be removed.
Warning - the following commands will completely destroy any existing Zimbra installation:
sudo -u zimbra /opt/zimbra/bin/zmcontrol stop
rpm -e zimbra-spell
rpm -e zimbra-ldap
rpm -e zimbra-mta
rpm -e zimbra-logger
rpm -e zimbra-snmp
rpm -e zimbra-apache
rpm -e zimbra-store
rpm -e zimbra-core
rm -Rf /opt/zimbra
- Run the zcs/install.sh and allow it to install all modules
- When the configuration menu appears open up a new terminal window and copy your ZCSLicense.xml file to /opt/zimbra/conf then change ownership and rights:
cp ZCSLicense.xml /opt/zimbra/conf
chown zimbra:zimbra /opt/zimbra/conf/ZCSLicense.xml
chmod 444 /opt/zimbra/conf/ZCSLicense.xml
- Returning to the configuration menu make sure that you configure the same domain, hostname, passwords as on the old server. During ZCS install, the following settings must be changed to match the original server settings:
- a. Zimbra LDAP Server – For Domain to create – identify the same default domain as on the original server.
- b. Zimbra Mailbox Server – An administrator’s account is automatically created.
- Make sure that the account name for Admin user to create is the same name as on the original server.
- Set the admin password the same as on the old server.
- Change the Spam training user and the Non-spam (HAM) training user account names to be the same as the spam account names on the original server.
- Global Document Account – This account name is automatically generated. Change the Global Document Account name to be the same account name as on the original server.
- c. Change any other settings on the new server to match the configuration on the original server.
- d. Disable auto-backup and starting of servers after configuration in the configuration menu:
11) Enable default backup schedule: no r) Start servers after configuration no
- Apply configuration changes, there will be one warning:
"WARNING: Document and Zimlet initialization skipped because Application Server was not configured to start."
Restoring to the new server:
As user zimbra do the following...
- Stop the new server, type zmcontrol stop
- If the old server had additional storage volumes configured, mount any additional volumes now.
- Delete the mysql data and re initialize an empty data directory. If you do not do this, zmrestoreoffline will have errors. As zimbra, type
- a. rm -rf /opt/zimbra/db/data/*
- b. /opt/zimbra/libexec/zmmyinit (The mySQL service is now running.)
- Copy the backup files from the old server or from an archive location to /opt/zimbra/backup.
- To restore the LDAP, type zmrestoreldap -lb <latest_label>.
If you are restoring large number of accounts, you may want to run this command with nohup so that the session does not terminate. (Observe whether the LDAP server is started successfully after the restore, it must be running for the next steps). Note: To find the LDAP session label to restore, type zmrestoreldap –lbs.
Note: The zmrestoreldap script included in ZCS 4.5.7 through ZCS 4.5.10 and ZCS 5.0 through ZCS 5.0.1 is broken. This is being tracked as Bug 23644: zmrestoreldap not taking accesslog db into consideration. The fix will be included in ZCS 4.5.11 and ZCS 5.0.2. You can also download an updated script with the fix from these links: ZCS 4.5.x: http://files.zimbra.com/downloads/4.5.10_GA/zmrestoreldap_4511 ZCS 5.0.x: http://files.zimbra.com/downloads/5.0.1_GA/zmrestoreldap_502
- Type zmconvertctl start. This is required before running zmrestoreoffline.
- To start the offline restore, type zmrestoreoffline -sys -a all -c -br. You may want to run nohup here also. To watch the progress, tail /opt/zimbra/log/mailbox.log. Note: Use –c on the command line so that accounts will be restored even if some accounts encounter errors during the offline restore process.
- Because some ZCS services are running at this point, type zmcontrol stop to stop all services.
- Remove any old backup sessions because these sessions are no longer valid. Type rm -rf /opt/zimbra/redolog/* /opt/zimbra/backup/*
- To start ZCS, type zmcontrol start.
- Remove the firewall rules and allow client access to the new server.
Rev 1 411/2007