Managing Planned and Unplanned Outages

Managing Planned Outages
Managing Unplanned Outages
Backing Up Pivotal tc Server

This section describes how to manage both planned and unplanned outages of Pivotal tc Server.

Managing Planned Outages

In a planned outage, you schedule a time when tc Runtime instances will be briefly unavailable so that you can perform maintenance on the instance or deployed applications, create cold backups, and so on. The procedure describes how to stop all tc Runtime instances.

Procedure

If you are using a Web Server as a load-balancer or proxy in front of one or more tc Runtime instances, drain all currently opened sessions between the Web Server and the tc Runtime instances.
On the computer on which the tc Runtime instances are installed, stop all instances. For example, on Unix:
```
tcserver stop demo-instance
```
See Starting and Stopping tc Runtime Instances for additional details, such as Windows instructions.

When you stop tc Runtime instances, the Web applications that are deployed to the instances are not available to users. You can now safely perform maintenance on the instance, such as update its configuration and create a cold backup.

Managing Unplanned Outages

An unplanned outage is one that you do not schedule. Unplanned outages can be minor, such as a power failure that causes the tc Server computer to shut down ungracefully, or more critical outages such as a hard-disk failure.

Typically, if you have fully restored and restarted the computer on which tc Server is installed, all you need to do next is start the tc Runtime instances. Check the catalina.out and catalina.log log files in the INSTANCE-DIR/logs directory to ensure that no failures occurred during startup and that the configuration files are not corrupted. Invoke your deployed applications to verify that they are working correctly.

If the log files indicate that the tc Runtime instance did not start because, for example, the configuration files are corrupted, or your deployed applications do not seem to be working correctly, you should restore the instance directory from a recent cold backup. The following procedure describes how to do this.

Procedure

Ensure that you have you have a recent cold backup of the tc Runtime instance that contains the last known good configuration and deployed Web applications.
If necessary, stop all tc Runtime instances. For example, on Unix:
```
tcserver stop demo-instance
```
See Starting and Stopping tc Runtime Instances for additional details, such as Windows instructions.
Change to the parent directory of the instance, then rename the instance directory. For example:
```
cd /var/opt/pivotal/pivotal-tc-server
mv demo-instance demo-instance-backup
```
Note: This is just a precautionary step; you can remove this temporary backup once you fully restore the instance from the cold backup.
Unzip or un-tar your backup appropriately. For example, if you created a TAR file on Unix as described in Backing Up tc Server and the TAR file is called myserverBackup-20120922.tar, execute the following commands:
```
cd /var/opt/pivotal/pivotal-tc-server/instances
tar xvf demo-instanceBackup-20120922.tar 
```
Start the instance to make your Web applications available again:
```
tcserver start demo-instance
```
Check the logs/catalina.out and logs/catalina.date.log files to ensure that the instance started without errors, then invoke your Web applications and ensure that they are working correctly.

If you lost all data on the computer on which tc Server was installed, first re-install tc Server and then follow the preceding procedure to restore each tc Runtime instance..

Backing Up Pivotal tc Server

When backing up tc Server, you need to create only backups of your tc Runtime instances; you do not need to back up the tc Server installation itself because you can always reinstall it from your original distribution if necessary.

Pivotal recommends that you always make cold backups of your instances, which means you ZIP or TAR up the instance directory after stopping the instance.

A hot backup refers to creating a ZIP or TAR file of the instance directory without first stopping the instance. Although on Unix this method might be possible, and you will likely be able to fully restore the instance from the hot backup, Microsoft Windows may prevent you from even creating the hot backup in the first place due to file-locking issues due to tc Runtime processes holding locks on files that you are trying to backup. For this reason, Pivotal does not recommend hot backups.

The following procedure describes how to perform a cold backup.

Procedure

Fully shut down the tc Runtime instances and any load-balancing Web Server as described in Managing Planned Outages.
Create a ZIP or a TAR file of each tc Runtime instance directory. For example, if your instances are located in the /var/opt/pivotal/pivotal-tc-server/instances directory, and you want to create a TAR file on Unix of the myserver instance:
```
prompt$ cd /var/opt/pivotal/pivotal-tc-server/instances
prompt$ tar cvf myserverBackup-20120922.tar myserver
```
This creates a TAR file called myserverBackup-20120922.tar with the top-most level being the instance directory (myserver in this case.)