Moving the THL File Location

The location of the THL directory where THL files are stored can be changed, either by using a symbolic link or by changing the configuration to point to the new directory:

• Changing the directory location using symbolic links can be used in an emergency if the space on a filesystem has been exhausted. See "Relocating THL Storage using Symbolic Links"
• Changing the directory location through reconfiguration can be used when a permanent change to the THL location is required. See "Relocating THL Storage using Configuration Changes".

Relocating THL Storage using Symbolic Links

In an emergency, the directory currently holding the THL information, can be moved using symbolic links to relocate the files to a location with more space.

Moving the THL location requires updating the location for a Replica by temporarily setting the Replica offline, updating the THL location, and re-enabling:

1. Put the replication service offline using trepctl:

   shell> trepctl -service alpha offline

2. Create a new directory, or attach a new filesystem and location on which the THL content will be located. You can use a directory on another filesystem or connect to a SAN, NFS or other filesystem where the new directory will be located. For example:

   shell> mkdir /mnt/data/thl

3. Copy the existing THL directory to the new directory location. For example:

   shell> rsync -r /opt/continuent/thl/* /mnt/data/thl/

4. Move the existing directory to a temporary location:

   shell> mv /opt/continuent/thl /opt/continuent/old-thl

5. Create a symbolic link from the new directory to the original directory location:

   shell> ln -s /mnt/data/thl /opt/continuent/thl

6. Put the replication service online using trepctl:

   shell> trepctl -service alpha online

Relocating THL Storage using Configuration Changes

To permanently change the directory currently holding the THL information can be reconfigured to a new directory location.

To update the location for a Replica by temporarily setting the Replica offline, updating the THL location, and re-enabling:

1. Put the replication service offline using trepctl:

   shell> trepctl -service alpha offline

2. Create a new directory, or attach a new filesystem and location on which the THL content will be located. You can use a directory on another filesystem or connect to a SAN, NFS or other filesystem where the new directory will be located. For example:

   shell> mkdir /mnt/data/thl

3. Copy the existing THL directory to the new directory location. For example:

   shell> rsync -r /opt/continuent/thl/* /mnt/data/thl/

4. Change the directory location using tpm to update the configuration for a specific host:

   shell> tpm update --thl-directory=/mnt/data/thl --host=host1

5. Put the replication service online using trepctl:

   shell> trepctl -service alpha online