This document describes the ssh/rsync based replication available since Solr1.1 This mechanism only works on systems that support removing open hard links.

These Scripts were superseded by the ReplicationHandler Java implementation of index replication that works over HTTP and was introduced in Solr1.4, and are no longer actively maintained.

All distribution scripts reside in solr/bin. All distribution configuration files reside in solr/conf. For more information on the distribution scripts and configuartion files, see SolrCollectionDistributionScripts. A more detailed description of the replication process can be found on CollectionDistribution. To learn how to monitor and debug that part of the system, see SolrCollectionDistributionStatusStats.

master Solr server

• Enable the rsyncd daemon by running rsyncd-enable.
• Start the rsync daemon by running rsyncd-start.
• Snapshots are taken by the Solr server after each commit and optimize request. They can also be taken manually by running snapshooter.
• Snapshots older than a certain number of days old can be removed automatically by configuring cron to run snapcleaner regularly. If necessary, additional cleanup can be done by running snapcleaner manually.
  
  

slave Solr server

• The user id under which the Solr distribution scripts run must be able to ssh/scp from the slave Solr server to the master Solr server without being prompted for a password. ssh is used to determine the lastest snapshot available on the master. scp is used to transfer distribution status and statistics back to the master.
• Enable the snappuller by running snappuller-enable.
• Configure cron to run snappuller regularly. It can also be run manually to pull the latest snapshot from the master on demand.
• Install the latest snapshot into Solr by running snapinstaller.
• Snapshots older than a certain number of days old can be removed automatically by configuring cron to run snapcleaner regularly. If necessary, additional cleanup can be done by running snapcleaner manually.